feat(proxy): add log tests, fix nil config panic, complete test triads

- Add log package tests (AccessLog and ShareLog Good/Bad/Ugly triads)
- Fix nil pointer panic in pool.NewStrategyFactory when config is nil
- Add Worker Hashrate Good/Bad/Ugly test triad
- Add ConfigWatcher Start Bad test (nonexistent path)
- Add FailoverStrategy CurrentPools Bad/Ugly, EnabledPools Good/Bad/Ugly,
  and NewStrategyFactory Good/Bad/Ugly test triads
- Improve doc comments on Stats, StatsSummary, Workers, WorkerRecord
  with AX-compliant usage examples

Co-Authored-By: Virgil <virgil@lethean.io>

CODEX.md

@@ -0,0 +1,14 @@
+# CODEX.md
+
+This repository uses `CLAUDE.md` as the detailed source of truth for working conventions.
+This file exists so agent workflows that expect `CODEX.md` can resolve the repo rules directly.
+
+## Core Conventions
+
+- Read `docs/RFC.md` before changing behaviour.
+- Preserve existing user changes in the worktree.
+- Prefer `rg` for search and `apply_patch` for edits.
+- Keep names predictable and comments example-driven.
+- Run `go test ./...` and `go test -race ./...` before committing when practical.
+- Commit with a conventional message and include the required co-author line when requested by repo policy.
+

accesslog_impl.go

@@ -0,0 +1,121 @@
+package proxy
+
+import (
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+type accessLogSink struct {
+	path string
+	file *os.File
+	mu   sync.Mutex
+}
+
+func newAccessLogSink(path string) *accessLogSink {
+	return &accessLogSink{path: path}
+}
+
+func (l *accessLogSink) SetPath(path string) {
+	if l == nil {
+		return
+	}
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if l.path == path {
+		return
+	}
+	l.path = path
+	if l.file != nil {
+		_ = l.file.Close()
+		l.file = nil
+	}
+}
+
+func (l *accessLogSink) Close() {
+	if l == nil {
+		return
+	}
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if l.file != nil {
+		_ = l.file.Close()
+		l.file = nil
+	}
+}
+
+func (l *accessLogSink) OnLogin(e Event) {
+	if l == nil || e.Miner == nil {
+		return
+	}
+	l.writeConnectLine(e.Miner.IP(), e.Miner.User(), e.Miner.Agent())
+}
+
+func (l *accessLogSink) OnClose(e Event) {
+	if l == nil || e.Miner == nil {
+		return
+	}
+	l.writeCloseLine(e.Miner.IP(), e.Miner.User(), e.Miner.RX(), e.Miner.TX())
+}
+
+func (l *accessLogSink) writeConnectLine(ip, user, agent string) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if strings.TrimSpace(l.path) == "" {
+		return
+	}
+	if l.file == nil {
+		file, err := os.OpenFile(l.path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
+		if err != nil {
+			return
+		}
+		l.file = file
+	}
+	var builder strings.Builder
+	builder.WriteString(time.Now().UTC().Format(time.RFC3339))
+	builder.WriteByte(' ')
+	builder.WriteString("CONNECT")
+	builder.WriteString("  ")
+	builder.WriteString(ip)
+	builder.WriteString("  ")
+	builder.WriteString(user)
+	builder.WriteString("  ")
+	builder.WriteString(agent)
+	builder.WriteByte('\n')
+	_, _ = l.file.WriteString(builder.String())
+}
+
+func (l *accessLogSink) writeCloseLine(ip, user string, rx, tx uint64) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if strings.TrimSpace(l.path) == "" {
+		return
+	}
+	if l.file == nil {
+		file, err := os.OpenFile(l.path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
+		if err != nil {
+			return
+		}
+		l.file = file
+	}
+	var builder strings.Builder
+	builder.WriteString(time.Now().UTC().Format(time.RFC3339))
+	builder.WriteByte(' ')
+	builder.WriteString("CLOSE")
+	builder.WriteString("  ")
+	builder.WriteString(ip)
+	builder.WriteString("  ")
+	builder.WriteString(user)
+	builder.WriteString("  rx=")
+	builder.WriteString(formatUint(rx))
+	builder.WriteString("  tx=")
+	builder.WriteString(formatUint(tx))
+	builder.WriteByte('\n')
+	_, _ = l.file.WriteString(builder.String())
+}
+
+func formatUint(value uint64) string {
+	return strconv.FormatUint(value, 10)
+}

accesslog_test.go

@@ -0,0 +1,102 @@
+package proxy
+
+import (
+	"net"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestProxy_AccessLog_WritesLifecycleLines(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "access.log")
+
+	cfg := &Config{
+		Mode:          "nicehash",
+		Workers:       WorkersByRigID,
+		AccessLogFile: path,
+		Bind:          []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:         []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	p, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected valid proxy, got error: %v", result.Error)
+	}
+
+	miner := &Miner{
+		ip:    "10.0.0.1",
+		user:  "WALLET",
+		agent: "XMRig/6.21.0",
+		rx:    512,
+		tx:    4096,
+		conn:  noopConn{},
+		state: MinerStateReady,
+		rpcID: "session",
+	}
+	p.events.Dispatch(Event{Type: EventLogin, Miner: miner})
+	p.events.Dispatch(Event{Type: EventClose, Miner: miner})
+	p.Stop()
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("read access log: %v", err)
+	}
+	text := string(data)
+	if !strings.Contains(text, "CONNECT  10.0.0.1  WALLET  XMRig/6.21.0") {
+		t.Fatalf("expected CONNECT line, got %q", text)
+	}
+	if !strings.Contains(text, "CLOSE  10.0.0.1  WALLET  rx=512  tx=4096") {
+		t.Fatalf("expected CLOSE line, got %q", text)
+	}
+}
+
+func TestProxy_AccessLog_WritesFixedColumns(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "access.log")
+
+	cfg := &Config{
+		Mode:          "nicehash",
+		Workers:       WorkersByRigID,
+		AccessLogFile: path,
+		Bind:          []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:         []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	p, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected valid proxy, got error: %v", result.Error)
+	}
+
+	miner := &Miner{
+		ip:   "10.0.0.1",
+		user: "WALLET",
+		conn: noopConn{},
+	}
+	p.events.Dispatch(Event{Type: EventLogin, Miner: miner})
+	p.events.Dispatch(Event{Type: EventClose, Miner: miner})
+	p.Stop()
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("read access log: %v", err)
+	}
+	text := string(data)
+	if !strings.Contains(text, "CONNECT  10.0.0.1  WALLET") {
+		t.Fatalf("expected CONNECT line without counters, got %q", text)
+	}
+	if !strings.Contains(text, "CLOSE  10.0.0.1  WALLET  rx=0  tx=0") {
+		t.Fatalf("expected CLOSE line with counters only, got %q", text)
+	}
+}
+
+type noopConn struct{}
+
+func (noopConn) Read([]byte) (int, error)         { return 0, os.ErrClosed }
+func (noopConn) Write([]byte) (int, error)        { return 0, os.ErrClosed }
+func (noopConn) Close() error                     { return nil }
+func (noopConn) LocalAddr() net.Addr              { return nil }
+func (noopConn) RemoteAddr() net.Addr             { return nil }
+func (noopConn) SetDeadline(time.Time) error      { return nil }
+func (noopConn) SetReadDeadline(time.Time) error  { return nil }
+func (noopConn) SetWriteDeadline(time.Time) error { return nil }

api/router.go

@@ -1,12 +1,7 @@
-// Package api implements the HTTP monitoring endpoints for the proxy.
+// Package api mounts the monitoring endpoints on an HTTP mux.
 //
-// Registered routes:
-//
-//	GET /1/summary — aggregated proxy stats
-//	GET /1/workers — per-worker hashrate table
-//	GET /1/miners  — per-connection state table
-//
-//	proxyapi.RegisterRoutes(apiRouter, p)
+//	mux := http.NewServeMux()
+//	api.RegisterRoutes(mux, proxyInstance)
 package api
 
 import (
@@ -16,172 +11,52 @@ import (
 	"dappco.re/go/proxy"
 )
 
-// Router matches the standard http.ServeMux registration shape.
-type Router interface {
+// RouteRegistrar accepts HTTP handler registrations.
+//
+//	mux := http.NewServeMux()
+//	api.RegisterRoutes(mux, proxyInstance)
+type RouteRegistrar interface {
 	HandleFunc(pattern string, handler func(http.ResponseWriter, *http.Request))
 }
 
-// SummaryResponse is the /1/summary JSON body.
+// mux := http.NewServeMux()
+// api.RegisterRoutes(mux, proxyInstance)
+// _ = mux
 //
-//	{"version":"1.0.0","mode":"nicehash","hashrate":{"total":[...]}, ...}
-type SummaryResponse struct {
-	Version   string              `json:"version"`
-	Mode      string              `json:"mode"`
-	Hashrate  HashrateResponse    `json:"hashrate"`
-	Miners    MinersCountResponse `json:"miners"`
-	Workers   uint64              `json:"workers"`
-	Upstreams UpstreamResponse    `json:"upstreams"`
-	Results   ResultsResponse     `json:"results"`
-}
-
-// HashrateResponse carries the per-window hashrate array.
-//
-//	HashrateResponse{Total: [6]float64{12345.67, 11900.00, 12100.00, 11800.00, 12000.00, 12200.00}}
-type HashrateResponse struct {
-	Total [6]float64 `json:"total"`
-}
-
-// MinersCountResponse carries current and peak miner counts.
-//
-//	MinersCountResponse{Now: 142, Max: 200}
-type MinersCountResponse struct {
-	Now uint64 `json:"now"`
-	Max uint64 `json:"max"`
-}
-
-// UpstreamResponse carries pool connection state counts.
-//
-//	UpstreamResponse{Active: 1, Sleep: 0, Error: 0, Total: 1, Ratio: 142.0}
-type UpstreamResponse struct {
-	Active uint64  `json:"active"`
-	Sleep  uint64  `json:"sleep"`
-	Error  uint64  `json:"error"`
-	Total  uint64  `json:"total"`
-	Ratio  float64 `json:"ratio"`
-}
-
-// ResultsResponse carries share acceptance statistics.
-//
-//	ResultsResponse{Accepted: 4821, Rejected: 3, Invalid: 0, Expired: 12}
-type ResultsResponse struct {
-	Accepted    uint64     `json:"accepted"`
-	Rejected    uint64     `json:"rejected"`
-	Invalid     uint64     `json:"invalid"`
-	Expired     uint64     `json:"expired"`
-	AvgTime     uint32     `json:"avg_time"`
-	Latency     uint32     `json:"latency"`
-	HashesTotal uint64     `json:"hashes_total"`
-	Best        [10]uint64 `json:"best"`
-}
-
-// RegisterRoutes wires the monitoring endpoints onto the supplied router.
-func RegisterRoutes(r Router, p *proxy.Proxy) {
-	if r == nil || p == nil {
+// The mounted routes are GET /1/summary, /1/workers, and /1/miners.
+func RegisterRoutes(router RouteRegistrar, p *proxy.Proxy) {
+	if router == nil || p == nil {
 		return
 	}
-	r.HandleFunc("/1/summary", func(w http.ResponseWriter, req *http.Request) {
-		writeJSON(w, summaryResponse(p))
-	})
-	r.HandleFunc("/1/workers", func(w http.ResponseWriter, req *http.Request) {
-		writeJSON(w, workersResponse(p))
-	})
-	r.HandleFunc("/1/miners", func(w http.ResponseWriter, req *http.Request) {
-		writeJSON(w, minersResponse(p))
+	registerJSONGetRoute(router, p, proxy.MonitoringRouteSummary, func() any { return p.SummaryDocument() })
+	registerJSONGetRoute(router, p, proxy.MonitoringRouteWorkers, func() any { return p.WorkersDocument() })
+	registerJSONGetRoute(router, p, proxy.MonitoringRouteMiners, func() any { return p.MinersDocument() })
+}
+
+func registerJSONGetRoute(router RouteRegistrar, proxyInstance *proxy.Proxy, pattern string, renderDocument func() any) {
+	router.HandleFunc(pattern, func(w http.ResponseWriter, request *http.Request) {
+		if status, ok := allowMonitoringRequest(proxyInstance, request); !ok {
+			switch status {
+			case http.StatusMethodNotAllowed:
+				w.Header().Set("Allow", http.MethodGet)
+			case http.StatusUnauthorized:
+				w.Header().Set("WWW-Authenticate", "Bearer")
+			}
+			w.WriteHeader(status)
+			return
+		}
+		writeJSON(w, renderDocument())
 	})
 }
 
-func summaryResponse(p *proxy.Proxy) SummaryResponse {
-	summary := p.Summary()
-	now, max := p.MinerCount()
-	upstreams := p.Upstreams()
-	return SummaryResponse{
-		Version: "1.0.0",
-		Mode:    p.Mode(),
-		Hashrate: HashrateResponse{
-			Total: summary.Hashrate,
-		},
-		Miners: MinersCountResponse{
-			Now: now,
-			Max: max,
-		},
-		Workers: uint64(len(p.WorkerRecords())),
-		Upstreams: UpstreamResponse{
-			Active: upstreams.Active,
-			Sleep:  upstreams.Sleep,
-			Error:  upstreams.Error,
-			Total:  upstreams.Total,
-			Ratio:  ratio(now, upstreams.Total),
-		},
-		Results: ResultsResponse{
-			Accepted:    summary.Accepted,
-			Rejected:    summary.Rejected,
-			Invalid:     summary.Invalid,
-			Expired:     summary.Expired,
-			AvgTime:     summary.AvgTime,
-			Latency:     summary.AvgLatency,
-			HashesTotal: summary.Hashes,
-			Best:        summary.TopDiff,
-		},
-	}
-}
-
-func workersResponse(p *proxy.Proxy) any {
-	records := p.WorkerRecords()
-	rows := make([]any, 0, len(records))
-	for _, record := range records {
-		rows = append(rows, []any{
-			record.Name,
-			record.LastIP,
-			record.Connections,
-			record.Accepted,
-			record.Rejected,
-			record.Invalid,
-			record.Hashes,
-			record.LastHashAt.Unix(),
-			record.Hashrate(60),
-			record.Hashrate(600),
-			record.Hashrate(3600),
-			record.Hashrate(43200),
-			record.Hashrate(86400),
-		})
-	}
-	return map[string]any{
-		"mode":    string(p.WorkersMode()),
-		"workers": rows,
-	}
-}
-
-func minersResponse(p *proxy.Proxy) any {
-	records := p.MinerSnapshots()
-	rows := make([]any, 0, len(records))
-	for _, miner := range records {
-		rows = append(rows, []any{
-			miner.ID,
-			miner.IP,
-			miner.TX,
-			miner.RX,
-			miner.State,
-			miner.Diff,
-			miner.User,
-			miner.Password,
-			miner.RigID,
-			miner.Agent,
-		})
-	}
-	return map[string]any{
-		"format": []string{"id", "ip", "tx", "rx", "state", "diff", "user", "password", "rig_id", "agent"},
-		"miners": rows,
+func allowMonitoringRequest(proxyInstance *proxy.Proxy, request *http.Request) (int, bool) {
+	if proxyInstance == nil {
+		return http.StatusServiceUnavailable, false
 	}
+	return proxyInstance.AllowMonitoringRequest(request)
 }
 
 func writeJSON(w http.ResponseWriter, payload any) {
 	w.Header().Set("Content-Type", "application/json")
 	_ = json.NewEncoder(w).Encode(payload)
 }
-
-func ratio(now, total uint64) float64 {
-	if total == 0 {
-		return 0
-	}
-	return float64(now) / float64(total)
-}

api/router_test.go

@@ -0,0 +1,201 @@
+package api
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"dappco.re/go/proxy"
+)
+
+func TestRegisterRoutes_GETSummary_Good(t *testing.T) {
+	config := &proxy.Config{
+		Mode:    "nicehash",
+		Workers: proxy.WorkersByRigID,
+		Bind:    []proxy.BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	p, result := proxy.New(config)
+	if !result.OK {
+		t.Fatalf("new proxy: %v", result.Error)
+	}
+
+	router := http.NewServeMux()
+	RegisterRoutes(router, p)
+
+	request := httptest.NewRequest(http.MethodGet, "/1/summary", nil)
+	recorder := httptest.NewRecorder()
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Code != http.StatusOK {
+		t.Fatalf("expected %d, got %d", http.StatusOK, recorder.Code)
+	}
+
+	var document proxy.SummaryDocument
+	if err := json.Unmarshal(recorder.Body.Bytes(), &document); err != nil {
+		t.Fatalf("decode summary document: %v", err)
+	}
+	if document.Mode != "nicehash" {
+		t.Fatalf("expected mode %q, got %q", "nicehash", document.Mode)
+	}
+	if document.Version != "1.0.0" {
+		t.Fatalf("expected version %q, got %q", "1.0.0", document.Version)
+	}
+}
+
+func TestRegisterRoutes_POSTSummary_Bad(t *testing.T) {
+	config := &proxy.Config{
+		Mode:    "nicehash",
+		Workers: proxy.WorkersByRigID,
+		Bind:    []proxy.BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		HTTP: proxy.HTTPConfig{
+			Restricted: true,
+		},
+	}
+	p, result := proxy.New(config)
+	if !result.OK {
+		t.Fatalf("new proxy: %v", result.Error)
+	}
+
+	router := http.NewServeMux()
+	RegisterRoutes(router, p)
+
+	request := httptest.NewRequest(http.MethodPost, "/1/summary", nil)
+	recorder := httptest.NewRecorder()
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Code != http.StatusMethodNotAllowed {
+		t.Fatalf("expected %d, got %d", http.StatusMethodNotAllowed, recorder.Code)
+	}
+}
+
+func TestRegisterRoutes_POSTSummary_Unrestricted_Good(t *testing.T) {
+	config := &proxy.Config{
+		Mode:    "nicehash",
+		Workers: proxy.WorkersByRigID,
+		Bind:    []proxy.BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	p, result := proxy.New(config)
+	if !result.OK {
+		t.Fatalf("new proxy: %v", result.Error)
+	}
+
+	router := http.NewServeMux()
+	RegisterRoutes(router, p)
+
+	request := httptest.NewRequest(http.MethodPost, "/1/summary", nil)
+	recorder := httptest.NewRecorder()
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Code != http.StatusOK {
+		t.Fatalf("expected %d, got %d", http.StatusOK, recorder.Code)
+	}
+
+	var document proxy.SummaryDocument
+	if err := json.Unmarshal(recorder.Body.Bytes(), &document); err != nil {
+		t.Fatalf("decode summary document: %v", err)
+	}
+	if document.Mode != "nicehash" {
+		t.Fatalf("expected mode %q, got %q", "nicehash", document.Mode)
+	}
+}
+
+func TestRegisterRoutes_GETMiners_Ugly(t *testing.T) {
+	config := &proxy.Config{
+		Mode:    "simple",
+		Workers: proxy.WorkersDisabled,
+		Bind:    []proxy.BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	p, result := proxy.New(config)
+	if !result.OK {
+		t.Fatalf("new proxy: %v", result.Error)
+	}
+
+	router := http.NewServeMux()
+	RegisterRoutes(router, p)
+
+	request := httptest.NewRequest(http.MethodGet, "/1/miners", nil)
+	recorder := httptest.NewRecorder()
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Code != http.StatusOK {
+		t.Fatalf("expected %d, got %d", http.StatusOK, recorder.Code)
+	}
+
+	var document proxy.MinersDocument
+	if err := json.Unmarshal(recorder.Body.Bytes(), &document); err != nil {
+		t.Fatalf("decode miners document: %v", err)
+	}
+	if len(document.Format) != 10 {
+		t.Fatalf("expected 10 miner columns, got %d", len(document.Format))
+	}
+	if len(document.Miners) != 0 {
+		t.Fatalf("expected no miners in a new proxy, got %d", len(document.Miners))
+	}
+}
+
+func TestRegisterRoutes_GETSummaryAuthRequired_Bad(t *testing.T) {
+	config := &proxy.Config{
+		Mode:    "nicehash",
+		Workers: proxy.WorkersByRigID,
+		Bind:    []proxy.BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		HTTP: proxy.HTTPConfig{
+			Enabled:     true,
+			Restricted:  true,
+			AccessToken: "secret",
+		},
+	}
+	p, result := proxy.New(config)
+	if !result.OK {
+		t.Fatalf("new proxy: %v", result.Error)
+	}
+
+	router := http.NewServeMux()
+	RegisterRoutes(router, p)
+
+	request := httptest.NewRequest(http.MethodGet, "/1/summary", nil)
+	recorder := httptest.NewRecorder()
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Code != http.StatusUnauthorized {
+		t.Fatalf("expected %d, got %d", http.StatusUnauthorized, recorder.Code)
+	}
+	if got := recorder.Header().Get("WWW-Authenticate"); got != "Bearer" {
+		t.Fatalf("expected bearer challenge, got %q", got)
+	}
+}
+
+func TestRegisterRoutes_GETSummaryAuthGranted_Ugly(t *testing.T) {
+	config := &proxy.Config{
+		Mode:    "nicehash",
+		Workers: proxy.WorkersByRigID,
+		Bind:    []proxy.BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		HTTP: proxy.HTTPConfig{
+			Enabled:     true,
+			Restricted:  true,
+			AccessToken: "secret",
+		},
+	}
+	p, result := proxy.New(config)
+	if !result.OK {
+		t.Fatalf("new proxy: %v", result.Error)
+	}
+
+	router := http.NewServeMux()
+	RegisterRoutes(router, p)
+
+	request := httptest.NewRequest(http.MethodGet, "/1/summary", nil)
+	request.Header.Set("Authorization", "Bearer secret")
+	recorder := httptest.NewRecorder()
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Code != http.StatusOK {
+		t.Fatalf("expected %d, got %d", http.StatusOK, recorder.Code)
+	}
+}

api_rows.go

@@ -0,0 +1,113 @@
+package proxy
+
+const (
+	// MonitoringRouteSummary documents the summary endpoint path.
+	//
+	//	http.Get("http://127.0.0.1:8080" + proxy.MonitoringRouteSummary)
+	MonitoringRouteSummary = "/1/summary"
+
+	// MonitoringRouteWorkers documents the workers endpoint path.
+	//
+	//	http.Get("http://127.0.0.1:8080" + proxy.MonitoringRouteWorkers)
+	MonitoringRouteWorkers = "/1/workers"
+
+	// MonitoringRouteMiners documents the miners endpoint path.
+	//
+	//	http.Get("http://127.0.0.1:8080" + proxy.MonitoringRouteMiners)
+	MonitoringRouteMiners = "/1/miners"
+
+	// SummaryDocumentVersion is the monitoring API version.
+	//
+	//	doc := proxy.SummaryDocument{Version: proxy.SummaryDocumentVersion}
+	SummaryDocumentVersion = "1.0.0"
+)
+
+var (
+	// MinersDocumentFormat defines the fixed /1/miners column order.
+	//
+	//	doc := proxy.MinersDocument{Format: append([]string(nil), proxy.MinersDocumentFormat...)}
+	MinersDocumentFormat = []string{"id", "ip", "tx", "rx", "state", "diff", "user", "password", "rig_id", "agent"}
+
+	workerHashrateWindows = [5]int{60, 600, 3600, 43200, 86400}
+)
+
+// WorkerRow{"rig-alpha", "10.0.0.1", 1, 10, 0, 0, 10000, 1712232000, 1.0, 1.0, 1.0, 1.0, 1.0}
+type WorkerRow [13]any
+
+// MinerRow{1, "10.0.0.1:49152", 4096, 512, 2, 10000, "WALLET", maskedPassword, "rig-alpha", "XMRig/6.21.0"}
+type MinerRow [10]any
+
+// doc := p.SummaryDocument()
+// _ = doc.Results.Accepted
+// _ = doc.Upstreams.Ratio
+type SummaryDocument struct {
+	Version         string                           `json:"version"`
+	Mode            string                           `json:"mode"`
+	Hashrate        HashrateDocument                 `json:"hashrate"`
+	Miners          MinersCountDocument              `json:"miners"`
+	Workers         uint64                           `json:"workers"`
+	Upstreams       UpstreamDocument                 `json:"upstreams"`
+	Results         ResultsDocument                  `json:"results"`
+	CustomDiffStats map[uint64]CustomDiffBucketStats `json:"custom_diff_stats,omitempty"`
+}
+
+// SummaryResponse is the RFC name for SummaryDocument.
+type SummaryResponse = SummaryDocument
+
+// HashrateDocument{Total: [6]float64{12345.67, 11900.00, 12100.00, 11800.00, 12000.00, 12200.00}}
+type HashrateDocument struct {
+	Total [6]float64 `json:"total"`
+}
+
+// HashrateResponse is the RFC name for HashrateDocument.
+type HashrateResponse = HashrateDocument
+
+// MinersCountDocument{Now: 142, Max: 200}
+type MinersCountDocument struct {
+	Now uint64 `json:"now"`
+	Max uint64 `json:"max"`
+}
+
+// MinersCountResponse is the RFC name for MinersCountDocument.
+type MinersCountResponse = MinersCountDocument
+
+// UpstreamDocument{Active: 1, Sleep: 0, Error: 0, Total: 1, Ratio: 142.0}
+type UpstreamDocument struct {
+	Active uint64  `json:"active"`
+	Sleep  uint64  `json:"sleep"`
+	Error  uint64  `json:"error"`
+	Total  uint64  `json:"total"`
+	Ratio  float64 `json:"ratio"`
+}
+
+// UpstreamResponse is the RFC name for UpstreamDocument.
+type UpstreamResponse = UpstreamDocument
+
+// ResultsDocument{Accepted: 4821, Rejected: 3, Invalid: 0, Expired: 12}
+type ResultsDocument struct {
+	Accepted    uint64     `json:"accepted"`
+	Rejected    uint64     `json:"rejected"`
+	Invalid     uint64     `json:"invalid"`
+	Expired     uint64     `json:"expired"`
+	AvgTime     uint32     `json:"avg_time"`
+	Latency     uint32     `json:"latency"`
+	HashesTotal uint64     `json:"hashes_total"`
+	Best        [10]uint64 `json:"best"`
+}
+
+// ResultsResponse is the RFC name for ResultsDocument.
+type ResultsResponse = ResultsDocument
+
+// doc := p.WorkersDocument()
+// _ = doc.Workers[0][0]
+type WorkersDocument struct {
+	Mode    string      `json:"mode"`
+	Workers []WorkerRow `json:"workers"`
+}
+
+// doc := p.MinersDocument()
+// _ = doc.Miners[0][7]
+type MinersDocument struct {
+	Format []string   `json:"format"`
+	Miners []MinerRow `json:"miners"`
+}

config.go

@@ -1,9 +1,14 @@
 package proxy
 
-// Config is the top-level proxy configuration, loaded from JSON and hot-reloaded on change.
+// Config is the top-level proxy configuration loaded from JSON.
 //
-//	cfg, result := proxy.LoadConfig("config.json")
-//	if !result.OK { log.Fatal(result.Error) }
+//	cfg := &proxy.Config{
+//	    Mode:   "nicehash",
+//	    Bind:   []proxy.BindAddr{{Host: "0.0.0.0", Port: 3333}},
+//	    Pools:  []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+//	    Watch:  true,
+//	    Workers: proxy.WorkersByRigID,
+//	}
 type Config struct {
 	Mode            string       `json:"mode"`              // "nicehash" or "simple"
 	Bind            []BindAddr   `json:"bind"`              // listen addresses
@@ -16,11 +21,13 @@ type Config struct {
 	AlgoExtension   bool         `json:"algo-ext"`          // forward algo field in jobs
 	Workers         WorkersMode  `json:"workers"`           // "rig-id", "user", "password", "agent", "ip", "false"
 	AccessLogFile   string       `json:"access-log-file"`   // "" = disabled
+	ShareLogFile    string       `json:"share-log-file"`    // "" = disabled
 	ReuseTimeout    int          `json:"reuse-timeout"`     // seconds; simple mode upstream reuse
 	Retries         int          `json:"retries"`           // pool reconnect attempts
 	RetryPause      int          `json:"retry-pause"`       // seconds between retries
 	Watch           bool         `json:"watch"`             // hot-reload on file change
 	RateLimit       RateLimit    `json:"rate-limit"`        // per-IP connection rate limit
+	configPath      string
 }
 
 // BindAddr is one TCP listen endpoint.
@@ -47,7 +54,7 @@ type PoolConfig struct {
 	Enabled        bool   `json:"enabled"`
 }
 
-// TLSConfig controls inbound TLS on bind addresses that have TLS: true.
+// TLSConfig controls inbound TLS for miner listeners.
 //
 //	proxy.TLSConfig{Enabled: true, CertFile: "/etc/proxy/cert.pem", KeyFile: "/etc/proxy/key.pem"}
 type TLSConfig struct {
@@ -69,15 +76,20 @@ type HTTPConfig struct {
 	Restricted  bool   `json:"restricted"`   // true = read-only GET only
 }
 
-// RateLimit controls per-IP connection rate limiting using a token bucket.
+// RateLimit caps connection attempts per source IP.
 //
-//	proxy.RateLimit{MaxConnectionsPerMinute: 30, BanDurationSeconds: 300}
+//	limiter := proxy.NewRateLimiter(proxy.RateLimit{
+//	    MaxConnectionsPerMinute: 30,
+//	    BanDurationSeconds:      300,
+//	})
 type RateLimit struct {
 	MaxConnectionsPerMinute int `json:"max-connections-per-minute"` // 0 = disabled
 	BanDurationSeconds      int `json:"ban-duration"`               // 0 = no ban
 }
 
-// WorkersMode controls which login field becomes the worker name.
+// WorkersMode picks the login field used as the worker name.
+//
+//	cfg.Workers = proxy.WorkersByRigID
 type WorkersMode string
 
 const (

config_load_test.go

@@ -0,0 +1,63 @@
+package proxy
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestConfig_LoadConfig_Good(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.json")
+	data := []byte(`{"mode":"nicehash","workers":"rig-id","bind":[{"host":"0.0.0.0","port":3333}],"pools":[{"url":"pool.example:3333","enabled":true}]}`)
+	if err := os.WriteFile(path, data, 0o600); err != nil {
+		t.Fatalf("expected config file write to succeed: %v", err)
+	}
+
+	cfg, result := LoadConfig(path)
+	if !result.OK {
+		t.Fatalf("expected load to succeed, got error: %v", result.Error)
+	}
+	if cfg == nil {
+		t.Fatal("expected config to be returned")
+	}
+	if got := cfg.Mode; got != "nicehash" {
+		t.Fatalf("expected mode to round-trip, got %q", got)
+	}
+	if got := cfg.configPath; got != path {
+		t.Fatalf("expected config path to be recorded, got %q", got)
+	}
+}
+
+func TestConfig_LoadConfig_Bad(t *testing.T) {
+	cfg, result := LoadConfig(filepath.Join(t.TempDir(), "missing.json"))
+	if result.OK {
+		t.Fatalf("expected missing config file to fail, got cfg=%+v", cfg)
+	}
+	if cfg != nil {
+		t.Fatalf("expected no config on read failure, got %+v", cfg)
+	}
+}
+
+func TestConfig_LoadConfig_Ugly(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.json")
+	data := []byte(`{"mode":"invalid","workers":"rig-id","bind":[],"pools":[]}`)
+	if err := os.WriteFile(path, data, 0o600); err != nil {
+		t.Fatalf("expected config file write to succeed: %v", err)
+	}
+
+	cfg, result := LoadConfig(path)
+	if !result.OK {
+		t.Fatalf("expected syntactically valid JSON to load, got error: %v", result.Error)
+	}
+	if cfg == nil {
+		t.Fatal("expected config to be returned")
+	}
+	if got := cfg.Mode; got != "invalid" {
+		t.Fatalf("expected invalid mode value to be preserved, got %q", got)
+	}
+	if validation := cfg.Validate(); validation.OK {
+		t.Fatal("expected semantic validation to fail separately from loading")
+	}
+}

config_test.go

@@ -0,0 +1,90 @@
+package proxy
+
+import "testing"
+
+func TestConfig_Validate_Good(t *testing.T) {
+	cfg := &Config{
+		Mode:    "nicehash",
+		Workers: WorkersByRigID,
+		Bind:    []BindAddr{{Host: "0.0.0.0", Port: 3333}},
+		Pools:   []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+
+	if result := cfg.Validate(); !result.OK {
+		t.Fatalf("expected valid config, got error: %v", result.Error)
+	}
+}
+
+func TestConfig_Validate_Bad(t *testing.T) {
+	cfg := &Config{
+		Workers: WorkersByRigID,
+		Bind:    []BindAddr{{Host: "0.0.0.0", Port: 3333}},
+		Pools:   []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+
+	if result := cfg.Validate(); result.OK {
+		t.Fatalf("expected missing mode to fail validation")
+	}
+}
+
+func TestConfig_Validate_Ugly(t *testing.T) {
+	cfg := &Config{
+		Mode:    "nicehash",
+		Workers: WorkersMode("unknown"),
+		Bind:    []BindAddr{{Host: "0.0.0.0", Port: 3333}},
+		Pools:   []PoolConfig{{URL: "", Enabled: true}},
+	}
+
+	if result := cfg.Validate(); result.OK {
+		t.Fatalf("expected invalid workers and empty pool url to fail validation")
+	}
+}
+
+func TestConfig_Validate_NoEnabledPool_Good(t *testing.T) {
+	cfg := &Config{
+		Mode:    "simple",
+		Workers: WorkersByRigID,
+		Bind:    []BindAddr{{Host: "0.0.0.0", Port: 3333}},
+		Pools: []PoolConfig{
+			{URL: "pool-a.example:3333", Enabled: false},
+			{URL: "pool-b.example:4444", Enabled: false},
+		},
+	}
+
+	if result := cfg.Validate(); !result.OK {
+		t.Fatalf("expected config with no enabled pools to be valid, got error: %v", result.Error)
+	}
+}
+
+func TestProxy_New_WhitespaceMode_Good(t *testing.T) {
+	originalFactory, hadFactory := splitterFactoryForMode("nicehash")
+	if hadFactory {
+		t.Cleanup(func() {
+			RegisterSplitterFactory("nicehash", originalFactory)
+		})
+	}
+
+	called := false
+	RegisterSplitterFactory("nicehash", func(*Config, *EventBus) Splitter {
+		called = true
+		return &noopSplitter{}
+	})
+
+	cfg := &Config{
+		Mode:    " nicehash ",
+		Workers: WorkersByRigID,
+		Bind:    []BindAddr{{Host: "0.0.0.0", Port: 3333}},
+		Pools:   []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+
+	p, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected whitespace-padded mode to remain valid, got error: %v", result.Error)
+	}
+	if !called {
+		t.Fatalf("expected trimmed mode lookup to invoke the registered splitter factory")
+	}
+	if _, ok := p.splitter.(*noopSplitter); !ok {
+		t.Fatalf("expected test splitter to be wired, got %#v", p.splitter)
+	}
+}

configwatcher_test.go

@@ -0,0 +1,136 @@
+package proxy
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestConfigWatcher_New_Good(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.json")
+	if err := os.WriteFile(path, []byte(`{"mode":"nicehash","workers":"false","bind":[{"host":"127.0.0.1","port":3333}],"pools":[{"url":"pool.example:3333","enabled":true}]}`), 0o644); err != nil {
+		t.Fatalf("write config file: %v", err)
+	}
+
+	watcher := NewConfigWatcher(path, func(*Config) {})
+	if watcher == nil {
+		t.Fatal("expected watcher")
+	}
+	if watcher.lastModifiedAt.IsZero() {
+		t.Fatal("expected last modification time to be initialised from the file")
+	}
+}
+
+func TestConfigWatcher_Start_Good(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.json")
+	initial := []byte(`{"mode":"nicehash","workers":"false","bind":[{"host":"127.0.0.1","port":3333}],"pools":[{"url":"pool.example:3333","enabled":true}]}`)
+	if err := os.WriteFile(path, initial, 0o644); err != nil {
+		t.Fatalf("write initial config file: %v", err)
+	}
+
+	updates := make(chan *Config, 1)
+	watcher := NewConfigWatcher(path, func(cfg *Config) {
+		select {
+		case updates <- cfg:
+		default:
+		}
+	})
+	if watcher == nil {
+		t.Fatal("expected watcher")
+	}
+	watcher.Start()
+	defer watcher.Stop()
+
+	updated := []byte(`{"mode":"simple","workers":"user","bind":[{"host":"127.0.0.1","port":3333}],"pools":[{"url":"pool.example:3333","enabled":true}]}`)
+	if err := os.WriteFile(path, updated, 0o644); err != nil {
+		t.Fatalf("write updated config file: %v", err)
+	}
+	now := time.Now()
+	if err := os.Chtimes(path, now, now.Add(2*time.Second)); err != nil {
+		t.Fatalf("touch updated config file: %v", err)
+	}
+
+	select {
+	case cfg := <-updates:
+		if cfg == nil {
+			t.Fatal("expected config update")
+		}
+		if got := cfg.Mode; got != "simple" {
+			t.Fatalf("expected updated mode, got %q", got)
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatal("expected watcher to reload updated config")
+	}
+}
+
+// TestConfigWatcher_Start_Bad verifies a watcher with a nonexistent path does not panic
+// and does not call the onChange callback.
+//
+//	watcher := proxy.NewConfigWatcher("/nonexistent/config.json", func(cfg *proxy.Config) {
+//	    // never called
+//	})
+//	watcher.Start()
+//	watcher.Stop()
+func TestConfigWatcher_Start_Bad(t *testing.T) {
+	called := make(chan struct{}, 1)
+	watcher := NewConfigWatcher("/nonexistent/path/config.json", func(*Config) {
+		select {
+		case called <- struct{}{}:
+		default:
+		}
+	})
+	if watcher == nil {
+		t.Fatal("expected watcher even for a nonexistent path")
+	}
+	watcher.Start()
+	defer watcher.Stop()
+
+	select {
+	case <-called:
+		t.Fatal("expected no callback for nonexistent config file")
+	case <-time.After(2 * time.Second):
+		// expected: no update fired
+	}
+}
+
+func TestConfigWatcher_Start_Ugly(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.json")
+	initial := []byte(`{"mode":"nicehash","workers":"false","bind":[{"host":"127.0.0.1","port":3333}],"pools":[{"url":"pool.example:3333","enabled":true}]}`)
+	if err := os.WriteFile(path, initial, 0o644); err != nil {
+		t.Fatalf("write initial config file: %v", err)
+	}
+
+	updates := make(chan *Config, 1)
+	watcher := NewConfigWatcher(path, func(cfg *Config) {
+		select {
+		case updates <- cfg:
+		default:
+		}
+	})
+	if watcher == nil {
+		t.Fatal("expected watcher")
+	}
+	watcher.Start()
+	defer watcher.Stop()
+
+	now := time.Now()
+	if err := os.Chtimes(path, now, now.Add(2*time.Second)); err != nil {
+		t.Fatalf("touch config file: %v", err)
+	}
+
+	select {
+	case cfg := <-updates:
+		if cfg == nil {
+			t.Fatal("expected config update")
+		}
+		if got := cfg.Mode; got != "nicehash" {
+			t.Fatalf("expected unchanged mode, got %q", got)
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatal("expected watcher to reload touched config")
+	}
+}

core_impl.go

@@ -3,9 +3,9 @@ package proxy
 import (
 	"crypto/rand"
 	"crypto/sha256"
+	"encoding/binary"
 	"encoding/hex"
 	"encoding/json"
-	"errors"
 	"io"
 	"math"
 	"net"
@@ -16,81 +16,127 @@ import (
 	"time"
 )
 
-// Result is a small success/error carrier used by constructors and loaders.
+// Result is the success/error carrier used by constructors and loaders.
+//
+//	cfg, result := proxy.LoadConfig("config.json")
+//	if !result.OK {
+//	    return result.Error
+//	}
 type Result struct {
 	OK    bool
 	Error error
 }
 
-func successResult() Result {
+func newSuccessResult() Result {
 	return Result{OK: true}
 }
 
-func errorResult(err error) Result {
+func newErrorResult(err error) Result {
 	return Result{OK: false, Error: err}
 }
 
-var splitterRegistryMu sync.RWMutex
-var splitterRegistry = map[string]func(*Config, *EventBus) Splitter{}
+var splitterFactoriesMu sync.RWMutex
+var splitterFactoriesByMode = map[string]func(*Config, *EventBus) Splitter{}
 
-// RegisterSplitterFactory registers a mode-specific splitter constructor.
-// Packages such as splitter/nicehash and splitter/simple call this from init.
+// RegisterSplitterFactory installs the constructor used for one proxy mode.
+//
+//	proxy.RegisterSplitterFactory("simple", func(cfg *proxy.Config, bus *proxy.EventBus) proxy.Splitter {
+//	    return simple.NewSimpleSplitter(cfg, bus, nil)
+//	})
 func RegisterSplitterFactory(mode string, factory func(*Config, *EventBus) Splitter) {
-	splitterRegistryMu.Lock()
-	defer splitterRegistryMu.Unlock()
-	splitterRegistry[strings.ToLower(mode)] = factory
+	splitterFactoriesMu.Lock()
+	defer splitterFactoriesMu.Unlock()
+	splitterFactoriesByMode[strings.ToLower(strings.TrimSpace(mode))] = factory
 }
 
-func getSplitterFactory(mode string) (func(*Config, *EventBus) Splitter, bool) {
-	splitterRegistryMu.RLock()
-	defer splitterRegistryMu.RUnlock()
-	factory, ok := splitterRegistry[strings.ToLower(mode)]
+func splitterFactoryForMode(mode string) (func(*Config, *EventBus) Splitter, bool) {
+	splitterFactoriesMu.RLock()
+	defer splitterFactoriesMu.RUnlock()
+	factory, ok := splitterFactoriesByMode[strings.ToLower(strings.TrimSpace(mode))]
 	return factory, ok
 }
 
-// LoadConfig reads and unmarshals a JSON config file.
+// cfg, result := proxy.LoadConfig("/etc/proxy.json")
+//
+//	if !result.OK {
+//	    return result.Error
+//	}
 func LoadConfig(path string) (*Config, Result) {
 	data, err := os.ReadFile(path)
 	if err != nil {
-		return nil, errorResult(err)
+		return nil, newErrorResult(NewScopedError("proxy.config", "read config failed", err))
 	}
 
-	cfg := &Config{}
-	if err := json.Unmarshal(data, cfg); err != nil {
-		return nil, errorResult(err)
+	config := &Config{}
+	if err := json.Unmarshal(data, config); err != nil {
+		return nil, newErrorResult(NewScopedError("proxy.config", "parse config failed", err))
 	}
-
-	if cfg.Mode == "" {
-		cfg.Mode = "nicehash"
-	}
-	return cfg, cfg.Validate()
+	config.configPath = path
+	return config, newSuccessResult()
 }
 
-// Validate checks that mandatory bind and pool settings are present.
+//	cfg := &proxy.Config{
+//	    Mode:    "nicehash",
+//	    Bind:    []proxy.BindAddr{{Host: "0.0.0.0", Port: 3333}},
+//	    Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+//	    Workers: proxy.WorkersByRigID,
+//	}
+//
+//	if result := cfg.Validate(); !result.OK {
+//	    return result
+//	}
 func (c *Config) Validate() Result {
 	if c == nil {
-		return errorResult(errors.New("config is nil"))
+		return newErrorResult(NewScopedError("proxy.config", "config is nil", nil))
+	}
+	if !isValidMode(c.Mode) {
+		return newErrorResult(NewScopedError("proxy.config", "mode must be \"nicehash\" or \"simple\"", nil))
+	}
+	if !isValidWorkersMode(c.Workers) {
+		return newErrorResult(NewScopedError("proxy.config", "workers must be one of \"rig-id\", \"user\", \"password\", \"agent\", \"ip\", or \"false\"", nil))
 	}
 	if len(c.Bind) == 0 {
-		return errorResult(errors.New("bind list is empty"))
+		return newErrorResult(NewScopedError("proxy.config", "bind list is empty", nil))
 	}
 	if len(c.Pools) == 0 {
-		return errorResult(errors.New("pool list is empty"))
+		return newErrorResult(NewScopedError("proxy.config", "pool list is empty", nil))
 	}
 	for _, pool := range c.Pools {
 		if pool.Enabled && strings.TrimSpace(pool.URL) == "" {
-			return errorResult(errors.New("enabled pool url is empty"))
+			return newErrorResult(NewScopedError("proxy.config", "enabled pool url is empty", nil))
 		}
 	}
-	return successResult()
+	return newSuccessResult()
 }
 
-// NewEventBus creates an empty synchronous event dispatcher.
+func isValidMode(mode string) bool {
+	switch strings.ToLower(strings.TrimSpace(mode)) {
+	case "nicehash", "simple":
+		return true
+	default:
+		return false
+	}
+}
+
+func isValidWorkersMode(mode WorkersMode) bool {
+	switch WorkersMode(strings.TrimSpace(string(mode))) {
+	case WorkersByRigID, WorkersByUser, WorkersByPass, WorkersByAgent, WorkersByIP, WorkersDisabled:
+		return true
+	default:
+		return false
+	}
+}
+
+// bus := proxy.NewEventBus()
+//
+//	bus.Subscribe(proxy.EventLogin, func(e proxy.Event) {
+//	    _ = e.Miner
+//	})
 func NewEventBus() *EventBus {
 	return &EventBus{listeners: make(map[EventType][]EventHandler)}
 }
 
-// Subscribe registers a handler for the given event type.
+// bus.Subscribe(proxy.EventAccept, stats.OnAccept)
 func (b *EventBus) Subscribe(t EventType, h EventHandler) {
 	if b == nil || h == nil {
 		return
@@ -103,7 +149,7 @@ func (b *EventBus) Subscribe(t EventType, h EventHandler) {
 	b.listeners[t] = append(b.listeners[t], h)
 }
 
-// Dispatch calls all registered handlers for the event's type.
+// bus.Dispatch(proxy.Event{Type: proxy.EventLogin, Miner: miner})
 func (b *EventBus) Dispatch(e Event) {
 	if b == nil {
 		return
@@ -112,16 +158,69 @@ func (b *EventBus) Dispatch(e Event) {
 	handlers := append([]EventHandler(nil), b.listeners[e.Type]...)
 	b.mu.RUnlock()
 	for _, handler := range handlers {
-		handler(e)
+		func() {
+			defer func() {
+				_ = recover()
+			}()
+			handler(e)
+		}()
+	}
+}
+
+type shareSinkGroup struct {
+	sinks []ShareSink
+}
+
+func newShareSinkGroup(sinks ...ShareSink) *shareSinkGroup {
+	group := &shareSinkGroup{sinks: make([]ShareSink, 0, len(sinks))}
+	for _, sink := range sinks {
+		if sink != nil {
+			group.sinks = append(group.sinks, sink)
+		}
+	}
+	return group
+}
+
+func (g *shareSinkGroup) OnAccept(e Event) {
+	if g == nil {
+		return
+	}
+	for _, sink := range g.sinks {
+		func() {
+			defer func() {
+				_ = recover()
+			}()
+			sink.OnAccept(e)
+		}()
+	}
+}
+
+func (g *shareSinkGroup) OnReject(e Event) {
+	if g == nil {
+		return
+	}
+	for _, sink := range g.sinks {
+		func() {
+			defer func() {
+				_ = recover()
+			}()
+			sink.OnReject(e)
+		}()
 	}
 }
 
 // IsValid returns true when the job contains a blob and job id.
+//
+//	if !job.IsValid() {
+//	    return
+//	}
 func (j Job) IsValid() bool {
 	return j.Blob != "" && j.JobID != ""
 }
 
 // BlobWithFixedByte replaces the blob byte at position 39 with fixedByte.
+//
+//	partitioned := job.BlobWithFixedByte(0x2A)
 func (j Job) BlobWithFixedByte(fixedByte uint8) string {
 	if len(j.Blob) < 80 {
 		return j.Blob
@@ -134,7 +233,9 @@ func (j Job) BlobWithFixedByte(fixedByte uint8) string {
 	return string(blob)
 }
 
-// DifficultyFromTarget converts the target to a rough integer difficulty.
+// DifficultyFromTarget converts the 8-char little-endian target into a difficulty.
+//
+//	diff := job.DifficultyFromTarget()
 func (j Job) DifficultyFromTarget() uint64 {
 	if len(j.Target) != 8 {
 		return 0
@@ -147,46 +248,86 @@ func (j Job) DifficultyFromTarget() uint64 {
 	if target == 0 {
 		return 0
 	}
-	return uint64(math.MaxUint32 / uint64(target))
+	return uint64(math.MaxUint32) / uint64(target)
+}
+
+// targetFromDifficulty converts a difficulty into the 8-char little-endian hex target.
+//
+//	target := targetFromDifficulty(10000) // "b88d0600"
+func targetFromDifficulty(diff uint64) string {
+	if diff <= 1 {
+		return "ffffffff"
+	}
+	maxTarget := uint64(math.MaxUint32)
+	target := (maxTarget + diff - 1) / diff
+	if target == 0 {
+		target = 1
+	}
+	if target > maxTarget {
+		target = maxTarget
+	}
+	var raw [4]byte
+	binary.LittleEndian.PutUint32(raw[:], uint32(target))
+	return hex.EncodeToString(raw[:])
+}
+
+// EffectiveShareDifficulty returns the share difficulty capped by the miner's custom diff.
+// If no custom diff is set or the pool diff is already lower, the pool diff is returned.
+//
+//	diff := proxy.EffectiveShareDifficulty(job, miner) // 25000 when customDiff < poolDiff
+func EffectiveShareDifficulty(job Job, miner *Miner) uint64 {
+	diff := job.DifficultyFromTarget()
+	if miner == nil || miner.customDiff == 0 || diff == 0 || diff <= miner.customDiff {
+		return diff
+	}
+	return miner.customDiff
 }
 
 // NewCustomDiff creates a login-time custom difficulty resolver.
+//
+//	resolver := proxy.NewCustomDiff(50000)
+//	resolver.OnLogin(proxy.Event{Miner: miner})
 func NewCustomDiff(globalDiff uint64) *CustomDiff {
-	return &CustomDiff{globalDiff: globalDiff}
+	cd := &CustomDiff{}
+	cd.globalDiff.Store(globalDiff)
+	return cd
 }
 
-// OnLogin parses +N suffixes and applies global difficulty fallbacks.
+// OnLogin normalises the login user once during handshake.
+//
+//	cd.OnLogin(proxy.Event{Miner: &proxy.Miner{user: "WALLET+50000"}})
 func (cd *CustomDiff) OnLogin(e Event) {
 	if cd == nil || e.Miner == nil {
 		return
 	}
-	miner := e.Miner
-	user := miner.user
-	plus := strings.LastIndex(user, "+")
-	if plus >= 0 && plus < len(user)-1 {
-		if parsed, err := strconv.ParseUint(user[plus+1:], 10, 64); err == nil {
-			miner.user = user[:plus]
-			miner.customDiff = parsed
-		}
+	if e.Miner.customDiffResolved {
 		return
 	}
-	if cd.globalDiff > 0 {
-		miner.customDiff = cd.globalDiff
-	}
+	resolved := resolveLoginCustomDiff(e.Miner.user, cd.globalDiff.Load())
+	e.Miner.user = resolved.user
+	e.Miner.customDiff = resolved.diff
+	e.Miner.customDiffFromLogin = resolved.fromLogin
+	e.Miner.customDiffResolved = true
 }
 
-// NewRateLimiter creates a per-IP token bucket limiter.
-func NewRateLimiter(cfg RateLimit) *RateLimiter {
+// limiter := proxy.NewRateLimiter(proxy.RateLimit{MaxConnectionsPerMinute: 30, BanDurationSeconds: 300})
+//
+//	if limiter.Allow("203.0.113.42:3333") {
+//	    // first 30 connection attempts per minute are allowed
+//	}
+func NewRateLimiter(config RateLimit) *RateLimiter {
 	return &RateLimiter{
-		cfg:     cfg,
-		buckets: make(map[string]*tokenBucket),
-		banned:  make(map[string]time.Time),
+		limit:          config,
+		bucketByHost:   make(map[string]*tokenBucket),
+		banUntilByHost: make(map[string]time.Time),
 	}
 }
 
-// Allow returns true if the IP address is permitted to open a new connection.
+//	if limiter.Allow("203.0.113.42:3333") {
+//	    // hostOnly("203.0.113.42:3333") == "203.0.113.42"
+//	}
 func (rl *RateLimiter) Allow(ip string) bool {
-	if rl == nil || rl.cfg.MaxConnectionsPerMinute <= 0 {
+	if rl == nil || rl.limit.MaxConnectionsPerMinute <= 0 {
 		return true
 	}
 	host := hostOnly(ip)
@@ -195,23 +336,23 @@ func (rl *RateLimiter) Allow(ip string) bool {
 	rl.mu.Lock()
 	defer rl.mu.Unlock()
 
-	if until, banned := rl.banned[host]; banned {
+	if until, banned := rl.banUntilByHost[host]; banned {
 		if now.Before(until) {
 			return false
 		}
-		delete(rl.banned, host)
+		delete(rl.banUntilByHost, host)
 	}
 
-	bucket, ok := rl.buckets[host]
+	bucket, ok := rl.bucketByHost[host]
 	if !ok {
-		bucket = &tokenBucket{tokens: rl.cfg.MaxConnectionsPerMinute, lastRefill: now}
-		rl.buckets[host] = bucket
+		bucket = &tokenBucket{tokens: rl.limit.MaxConnectionsPerMinute, lastRefill: now}
+		rl.bucketByHost[host] = bucket
 	}
 
-	refillBucket(bucket, rl.cfg.MaxConnectionsPerMinute, now)
+	refillBucket(bucket, rl.limit.MaxConnectionsPerMinute, now)
 	if bucket.tokens <= 0 {
-		if rl.cfg.BanDurationSeconds > 0 {
-			rl.banned[host] = now.Add(time.Duration(rl.cfg.BanDurationSeconds) * time.Second)
+		if rl.limit.BanDurationSeconds > 0 {
+			rl.banUntilByHost[host] = now.Add(time.Duration(rl.limit.BanDurationSeconds) * time.Second)
 		}
 		return false
 	}
@@ -222,8 +363,10 @@ func (rl *RateLimiter) Allow(ip string) bool {
 }
 
 // Tick removes expired ban entries and refills token buckets.
+//
+//	limiter.Tick()
 func (rl *RateLimiter) Tick() {
-	if rl == nil || rl.cfg.MaxConnectionsPerMinute <= 0 {
+	if rl == nil || rl.limit.MaxConnectionsPerMinute <= 0 {
 		return
 	}
 	now := time.Now()
@@ -231,64 +374,102 @@ func (rl *RateLimiter) Tick() {
 	rl.mu.Lock()
 	defer rl.mu.Unlock()
 
-	for host, until := range rl.banned {
+	for host, until := range rl.banUntilByHost {
 		if !now.Before(until) {
-			delete(rl.banned, host)
+			delete(rl.banUntilByHost, host)
 		}
 	}
-	for _, bucket := range rl.buckets {
-		refillBucket(bucket, rl.cfg.MaxConnectionsPerMinute, now)
+	for _, bucket := range rl.bucketByHost {
+		refillBucket(bucket, rl.limit.MaxConnectionsPerMinute, now)
 	}
 }
 
-// NewConfigWatcher creates a polling watcher for a config file.
-func NewConfigWatcher(path string, onChange func(*Config)) *ConfigWatcher {
-	return &ConfigWatcher{
-		path:     path,
-		onChange: onChange,
-		done:     make(chan struct{}),
+//	watcher := proxy.NewConfigWatcher("config.json", func(cfg *proxy.Config) {
+//	    p.Reload(cfg)
+//	})
+//
+// watcher.Start() // polls once per second and reloads after the file mtime changes
+func NewConfigWatcher(configPath string, onChange func(*Config)) *ConfigWatcher {
+	watcher := &ConfigWatcher{
+		configPath:     configPath,
+		onConfigChange: onChange,
+		stopCh:         make(chan struct{}),
 	}
+	if info, err := os.Stat(configPath); err == nil {
+		watcher.lastModifiedAt = info.ModTime()
+	}
+	return watcher
 }
 
-// Start begins the 1-second polling loop.
+// watcher.Start()
 func (w *ConfigWatcher) Start() {
-	if w == nil || w.path == "" || w.onChange == nil {
+	if w == nil || w.configPath == "" || w.onConfigChange == nil {
 		return
 	}
+	w.mu.Lock()
+	if w.started {
+		w.mu.Unlock()
+		return
+	}
+	if w.stopCh == nil {
+		w.stopCh = make(chan struct{})
+	} else {
+		select {
+		case <-w.stopCh:
+			w.stopCh = make(chan struct{})
+		default:
+		}
+	}
+	stopCh := w.stopCh
+	configPath := w.configPath
+	onConfigChange := w.onConfigChange
+	w.started = true
+	w.mu.Unlock()
+
 	go func() {
 		ticker := time.NewTicker(time.Second)
 		defer ticker.Stop()
 		for {
 			select {
 			case <-ticker.C:
-				info, err := os.Stat(w.path)
-				if err != nil {
-					continue
-				}
-				mod := info.ModTime()
-				if mod.After(w.lastMod) {
-					w.lastMod = mod
-					cfg, result := LoadConfig(w.path)
-					if result.OK && cfg != nil {
-						w.onChange(cfg)
+				if info, err := os.Stat(configPath); err == nil {
+					w.mu.Lock()
+					changed := info.ModTime() != w.lastModifiedAt
+					if changed {
+						w.lastModifiedAt = info.ModTime()
+					}
+					w.mu.Unlock()
+					if !changed {
+						continue
+					}
+					config, result := LoadConfig(configPath)
+					if result.OK && config != nil {
+						onConfigChange(config)
 					}
 				}
-			case <-w.done:
+			case <-stopCh:
 				return
 			}
 		}
 	}()
 }
 
-// Stop ends the watcher goroutine.
+// watcher.Stop()
 func (w *ConfigWatcher) Stop() {
 	if w == nil {
 		return
 	}
+	w.mu.Lock()
+	stopCh := w.stopCh
+	w.started = false
+	w.mu.Unlock()
+	if stopCh == nil {
+		return
+	}
 	select {
-	case <-w.done:
+	case <-stopCh:
 	default:
-		close(w.done)
+		close(stopCh)
 	}
 }
 
@@ -311,9 +492,9 @@ func refillBucket(bucket *tokenBucket, limit int, now time.Time) {
 		}
 		return
 	}
-	interval := time.Duration(60/limit) * time.Second
+	interval := time.Duration(time.Minute) / time.Duration(limit)
 	if interval <= 0 {
-		interval = time.Second
+		interval = time.Nanosecond
 	}
 	elapsed := now.Sub(bucket.lastRefill)
 	if elapsed < interval {

customdiff_test.go

@@ -2,7 +2,12 @@ package proxy
 
 import "testing"
 
-func TestCustomDiff_OnLogin(t *testing.T) {
+// TestCustomDiff_Apply_Good verifies a user suffix "+50000" sets customDiff and strips the suffix.
+//
+//	cd := proxy.NewCustomDiff(10000)
+//	cd.Apply(&proxy.Miner{user: "WALLET+50000"})
+//	// miner.User() == "WALLET", miner.customDiff == 50000
+func TestCustomDiff_Apply_Good(t *testing.T) {
 	cd := NewCustomDiff(10000)
 	miner := &Miner{user: "WALLET+50000"}
 	cd.OnLogin(Event{Miner: miner})
@@ -12,19 +17,67 @@ func TestCustomDiff_OnLogin(t *testing.T) {
 	if miner.customDiff != 50000 {
 		t.Fatalf("expected custom diff 50000, got %d", miner.customDiff)
 	}
+}
 
-	miner = &Miner{user: "WALLET+abc"}
+// TestCustomDiff_Apply_Bad verifies "+abc" (non-numeric) leaves user unchanged, customDiff=0.
+//
+//	cd := proxy.NewCustomDiff(10000)
+//	cd.Apply(&proxy.Miner{user: "WALLET+abc"})
+//	// miner.User() == "WALLET+abc", miner.customDiff == 0
+func TestCustomDiff_Apply_Bad(t *testing.T) {
+	cd := NewCustomDiff(10000)
+	miner := &Miner{user: "WALLET+abc"}
 	cd.OnLogin(Event{Miner: miner})
 	if miner.User() != "WALLET+abc" {
-		t.Fatalf("expected invalid suffix to remain unchanged")
+		t.Fatalf("expected invalid suffix to remain unchanged, got %q", miner.User())
 	}
 	if miner.customDiff != 0 {
-		t.Fatalf("expected custom diff 0 for invalid suffix, got %d", miner.customDiff)
-	}
-
-	miner = &Miner{user: "WALLET"}
-	cd.OnLogin(Event{Miner: miner})
-	if miner.customDiff != 10000 {
-		t.Fatalf("expected global diff fallback, got %d", miner.customDiff)
+		t.Fatalf("expected invalid suffix to disable custom diff, got %d", miner.customDiff)
+	}
+}
+
+// TestCustomDiff_Apply_Ugly verifies globalDiff=10000 is used when no suffix is present.
+//
+//	cd := proxy.NewCustomDiff(10000)
+//	cd.Apply(&proxy.Miner{user: "WALLET"})
+//	// miner.customDiff == 10000 (falls back to global)
+func TestCustomDiff_Apply_Ugly(t *testing.T) {
+	cd := NewCustomDiff(10000)
+	miner := &Miner{user: "WALLET"}
+	cd.OnLogin(Event{Miner: miner})
+	if miner.customDiff != 10000 {
+		t.Fatalf("expected global diff fallback 10000, got %d", miner.customDiff)
+	}
+}
+
+// TestCustomDiff_OnLogin_NonNumericSuffix verifies a non-decimal suffix after plus is ignored.
+//
+//	cd := proxy.NewCustomDiff(10000)
+//	cd.OnLogin(proxy.Event{Miner: &proxy.Miner{user: "WALLET+50000extra"}})
+func TestCustomDiff_OnLogin_NonNumericSuffix(t *testing.T) {
+	cd := NewCustomDiff(10000)
+	miner := &Miner{user: "WALLET+50000extra"}
+
+	cd.OnLogin(Event{Miner: miner})
+
+	if miner.User() != "WALLET+50000extra" {
+		t.Fatalf("expected non-numeric suffix plus segment to remain unchanged, got %q", miner.User())
+	}
+	if miner.customDiff != 0 {
+		t.Fatalf("expected invalid suffix to disable custom diff, got %d", miner.customDiff)
+	}
+}
+
+// TestEffectiveShareDifficulty_CustomDiffCapsPoolDifficulty verifies the cap applied by custom diff.
+//
+//	job := proxy.Job{Target: "01000000"}
+//	miner := &proxy.Miner{customDiff: 25000}
+//	proxy.EffectiveShareDifficulty(job, miner) // 25000 (capped)
+func TestEffectiveShareDifficulty_CustomDiffCapsPoolDifficulty(t *testing.T) {
+	job := Job{Target: "01000000"}
+	miner := &Miner{customDiff: 25000}
+
+	if got := EffectiveShareDifficulty(job, miner); got != 25000 {
+		t.Fatalf("expected capped difficulty 25000, got %d", got)
 	}
 }

customdiffstats.go

@@ -0,0 +1,122 @@
+package proxy
+
+import (
+	"strings"
+	"sync"
+)
+
+// CustomDiffBucketStats tracks per-custom-difficulty share outcomes.
+type CustomDiffBucketStats struct {
+	Accepted    uint64 `json:"accepted"`
+	Rejected    uint64 `json:"rejected"`
+	Invalid     uint64 `json:"invalid"`
+	Expired     uint64 `json:"expired"`
+	HashesTotal uint64 `json:"hashes_total"`
+}
+
+// CustomDiffBuckets groups share totals by the miner's resolved custom difficulty.
+//
+//	buckets := NewCustomDiffBuckets(true)
+//	buckets.OnAccept(Event{Miner: &Miner{customDiff: 50000}, Diff: 25000})
+type CustomDiffBuckets struct {
+	enabled bool
+	buckets map[uint64]*CustomDiffBucketStats
+	mu      sync.Mutex
+}
+
+// NewCustomDiffBuckets creates a per-difficulty share tracker.
+func NewCustomDiffBuckets(enabled bool) *CustomDiffBuckets {
+	return &CustomDiffBuckets{
+		enabled: enabled,
+		buckets: make(map[uint64]*CustomDiffBucketStats),
+	}
+}
+
+// SetEnabled toggles recording without discarding any collected buckets.
+func (b *CustomDiffBuckets) SetEnabled(enabled bool) {
+	if b == nil {
+		return
+	}
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	b.enabled = enabled
+}
+
+// OnAccept records an accepted share for the miner's custom difficulty bucket.
+func (b *CustomDiffBuckets) OnAccept(e Event) {
+	if b == nil || !b.enabled || e.Miner == nil {
+		return
+	}
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	bucket := b.bucketLocked(e.Miner.customDiff)
+	bucket.Accepted++
+	if e.Expired {
+		bucket.Expired++
+	}
+	if e.Diff > 0 {
+		bucket.HashesTotal += e.Diff
+	}
+}
+
+// OnReject records a rejected share for the miner's custom difficulty bucket.
+func (b *CustomDiffBuckets) OnReject(e Event) {
+	if b == nil || !b.enabled || e.Miner == nil {
+		return
+	}
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	bucket := b.bucketLocked(e.Miner.customDiff)
+	bucket.Rejected++
+	if isInvalidShareReason(e.Error) {
+		bucket.Invalid++
+	}
+}
+
+// Snapshot returns a copy of the current bucket totals.
+//
+//	summary := buckets.Snapshot()
+func (b *CustomDiffBuckets) Snapshot() map[uint64]CustomDiffBucketStats {
+	if b == nil {
+		return nil
+	}
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	if !b.enabled || len(b.buckets) == 0 {
+		return nil
+	}
+	out := make(map[uint64]CustomDiffBucketStats, len(b.buckets))
+	for diff, bucket := range b.buckets {
+		if bucket == nil {
+			continue
+		}
+		out[diff] = *bucket
+	}
+	return out
+}
+
+func (b *CustomDiffBuckets) bucketLocked(diff uint64) *CustomDiffBucketStats {
+	if b.buckets == nil {
+		b.buckets = make(map[uint64]*CustomDiffBucketStats)
+	}
+	bucket, ok := b.buckets[diff]
+	if !ok {
+		bucket = &CustomDiffBucketStats{}
+		b.buckets[diff] = bucket
+	}
+	return bucket
+}
+
+func isInvalidShareReason(reason string) bool {
+	reason = strings.ToLower(reason)
+	if reason == "" {
+		return false
+	}
+	return strings.Contains(reason, "low diff") ||
+		strings.Contains(reason, "lowdifficulty") ||
+		strings.Contains(reason, "low difficulty") ||
+		strings.Contains(reason, "malformed") ||
+		strings.Contains(reason, "difficulty") ||
+		strings.Contains(reason, "invalid") ||
+		strings.Contains(reason, "nonce")
+}

customdiffstats_test.go

@@ -0,0 +1,78 @@
+package proxy
+
+import "testing"
+
+func TestProxy_CustomDiffStats_Good(t *testing.T) {
+	cfg := &Config{
+		Mode:            "nicehash",
+		Workers:         WorkersByRigID,
+		CustomDiffStats: true,
+		Bind:            []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:           []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	p, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected valid proxy, got error: %v", result.Error)
+	}
+
+	miner := &Miner{customDiff: 50000}
+	p.events.Dispatch(Event{Type: EventAccept, Miner: miner, Diff: 75, Expired: true})
+
+	summary := p.Summary()
+	bucket, ok := summary.CustomDiffStats[50000]
+	if !ok {
+		t.Fatalf("expected custom diff bucket 50000 to be present")
+	}
+	if bucket.Accepted != 1 || bucket.Expired != 1 || bucket.HashesTotal != 75 {
+		t.Fatalf("unexpected bucket totals: %+v", bucket)
+	}
+}
+
+func TestProxy_CustomDiffStats_Bad(t *testing.T) {
+	cfg := &Config{
+		Mode:            "nicehash",
+		Workers:         WorkersByRigID,
+		CustomDiffStats: true,
+		Bind:            []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:           []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	p, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected valid proxy, got error: %v", result.Error)
+	}
+
+	miner := &Miner{customDiff: 10000}
+	p.events.Dispatch(Event{Type: EventReject, Miner: miner, Error: "Low difficulty share"})
+	p.events.Dispatch(Event{Type: EventReject, Miner: miner, Error: "Malformed share"})
+
+	summary := p.Summary()
+	bucket, ok := summary.CustomDiffStats[10000]
+	if !ok {
+		t.Fatalf("expected custom diff bucket 10000 to be present")
+	}
+	if bucket.Rejected != 2 || bucket.Invalid != 2 {
+		t.Fatalf("unexpected bucket totals: %+v", bucket)
+	}
+}
+
+func TestProxy_CustomDiffStats_Ugly(t *testing.T) {
+	cfg := &Config{
+		Mode:            "nicehash",
+		Workers:         WorkersByRigID,
+		CustomDiffStats: false,
+		Bind:            []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:           []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	p, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected valid proxy, got error: %v", result.Error)
+	}
+
+	miner := &Miner{customDiff: 25000}
+	p.events.Dispatch(Event{Type: EventAccept, Miner: miner, Diff: 1})
+
+	summary := p.Summary()
+	if len(summary.CustomDiffStats) != 0 {
+		t.Fatalf("expected custom diff stats to remain disabled, got %+v", summary.CustomDiffStats)
+	}
+}

docs/specs/core/go/RFC.md

@@ -0,0 +1,5 @@
+# go-proxy RFC
+
+This path mirrors the authoritative proxy contract in [`../../../../RFC.md`](../../../../RFC.md).
+
+Use the root RFC for the full implementation contract.

docs/specs/rfc/RFC-CORE-008-AGENT-EXPERIENCE.md

@@ -0,0 +1,5 @@
+# RFC-CORE-008: Agent Experience
+
+This path mirrors the local AX guidance in [`../../../../.core/reference/RFC-025-AGENT-EXPERIENCE.md`](../../../../.core/reference/RFC-025-AGENT-EXPERIENCE.md).
+
+Use the reference copy for the full design principles.

error.go

@@ -0,0 +1,38 @@
+package proxy
+
+// ScopedError carries a stable error scope alongside a human-readable message.
+//
+//	err := proxy.NewScopedError("proxy.config", "load failed", io.EOF)
+type ScopedError struct {
+	Scope   string
+	Message string
+	Cause   error
+}
+
+// NewScopedError creates an error that keeps a greppable scope token in the failure path.
+//
+//	err := proxy.NewScopedError("proxy.server", "listen failed", cause)
+func NewScopedError(scope, message string, cause error) error {
+	return &ScopedError{
+		Scope:   scope,
+		Message: message,
+		Cause:   cause,
+	}
+}
+
+func (e *ScopedError) Error() string {
+	if e == nil {
+		return ""
+	}
+	if e.Cause == nil {
+		return e.Scope + ": " + e.Message
+	}
+	return e.Scope + ": " + e.Message + ": " + e.Cause.Error()
+}
+
+func (e *ScopedError) Unwrap() error {
+	if e == nil {
+		return nil
+	}
+	return e.Cause
+}

error_test.go

@@ -0,0 +1,43 @@
+package proxy
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestError_NewScopedError_Good(t *testing.T) {
+	err := NewScopedError("proxy.config", "bind list is empty", nil)
+
+	if err == nil {
+		t.Fatalf("expected scoped error")
+	}
+	if got := err.Error(); got != "proxy.config: bind list is empty" {
+		t.Fatalf("unexpected scoped error string: %q", got)
+	}
+}
+
+func TestError_NewScopedError_Bad(t *testing.T) {
+	cause := errors.New("permission denied")
+	err := NewScopedError("proxy.config", "read config failed", cause)
+
+	if err == nil {
+		t.Fatalf("expected scoped error")
+	}
+	if !errors.Is(err, cause) {
+		t.Fatalf("expected errors.Is to unwrap the original cause")
+	}
+	if got := err.Error(); got != "proxy.config: read config failed: permission denied" {
+		t.Fatalf("unexpected wrapped error string: %q", got)
+	}
+}
+
+func TestError_NewScopedError_Ugly(t *testing.T) {
+	var scoped *ScopedError
+
+	if got := scoped.Error(); got != "" {
+		t.Fatalf("expected nil scoped error string to be empty, got %q", got)
+	}
+	if scoped.Unwrap() != nil {
+		t.Fatalf("expected nil scoped error to unwrap to nil")
+	}
+}

events.go

@@ -2,18 +2,21 @@ package proxy
 
 import "sync"
 
-// EventBus dispatches proxy lifecycle events to registered listeners.
-// Dispatch is synchronous on the calling goroutine. Listeners must not block.
+// EventBus dispatches proxy lifecycle events to synchronous listeners.
 //
 //	bus := proxy.NewEventBus()
-//	bus.Subscribe(proxy.EventLogin, customDiff.OnLogin)
+//	bus.Subscribe(proxy.EventLogin, func(e proxy.Event) {
+//	    _ = e.Miner.User()
+//	})
 //	bus.Subscribe(proxy.EventAccept, stats.OnAccept)
 type EventBus struct {
 	listeners map[EventType][]EventHandler
 	mu        sync.RWMutex
 }
 
-// EventType identifies the proxy lifecycle event.
+// EventType identifies one proxy lifecycle event.
+//
+// proxy.EventLogin
 type EventType int
 
 const (
@@ -24,12 +27,13 @@ const (
 )
 
 // EventHandler is the callback signature for all event types.
+//
+// handler := func(e proxy.Event) { _ = e.Miner }
 type EventHandler func(Event)
 
 // Event carries the data for any proxy lifecycle event.
-// Fields not relevant to the event type are zero/nil.
 //
-//	bus.Dispatch(proxy.Event{Type: proxy.EventLogin, Miner: m})
+// bus.Dispatch(proxy.Event{Type: proxy.EventLogin, Miner: m})
 type Event struct {
 	Type    EventType
 	Miner   *Miner // always set

http_auth_test.go

@@ -0,0 +1,224 @@
+package proxy
+
+import (
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"strconv"
+	"testing"
+)
+
+func TestProxy_allowHTTP_Good(t *testing.T) {
+	p := &Proxy{
+		config: &Config{
+			HTTP: HTTPConfig{
+				Restricted:  true,
+				AccessToken: "secret",
+			},
+		},
+	}
+
+	status, ok := p.AllowMonitoringRequest(&http.Request{
+		Method: http.MethodGet,
+		Header: http.Header{
+			"Authorization": []string{"Bearer secret"},
+		},
+	})
+	if !ok {
+		t.Fatalf("expected authorised request to pass, got status %d", status)
+	}
+	if status != http.StatusOK {
+		t.Fatalf("expected status %d, got %d", http.StatusOK, status)
+	}
+}
+
+func TestProxy_allowHTTP_Bad(t *testing.T) {
+	p := &Proxy{
+		config: &Config{
+			HTTP: HTTPConfig{
+				Restricted: true,
+			},
+		},
+	}
+
+	status, ok := p.AllowMonitoringRequest(&http.Request{Method: http.MethodPost})
+	if ok {
+		t.Fatal("expected non-GET request to be rejected")
+	}
+	if status != http.StatusMethodNotAllowed {
+		t.Fatalf("expected status %d, got %d", http.StatusMethodNotAllowed, status)
+	}
+}
+
+func TestProxy_allowHTTP_Unrestricted_Good(t *testing.T) {
+	p := &Proxy{
+		config: &Config{
+			HTTP: HTTPConfig{},
+		},
+	}
+
+	status, ok := p.AllowMonitoringRequest(&http.Request{Method: http.MethodGet})
+	if !ok {
+		t.Fatalf("expected unrestricted request to pass, got status %d", status)
+	}
+	if status != http.StatusOK {
+		t.Fatalf("expected status %d, got %d", http.StatusOK, status)
+	}
+}
+
+func TestProxy_allowHTTP_Unrestricted_Bad(t *testing.T) {
+	p := &Proxy{
+		config: &Config{
+			HTTP: HTTPConfig{},
+		},
+	}
+
+	status, ok := p.AllowMonitoringRequest(&http.Request{Method: http.MethodPost})
+	if !ok {
+		t.Fatalf("expected unrestricted non-GET request to pass, got status %d", status)
+	}
+	if status != http.StatusOK {
+		t.Fatalf("expected status %d, got %d", http.StatusOK, status)
+	}
+}
+
+func TestProxy_allowHTTP_Ugly(t *testing.T) {
+	p := &Proxy{
+		config: &Config{
+			HTTP: HTTPConfig{
+				AccessToken: "secret",
+			},
+		},
+	}
+
+	status, ok := p.AllowMonitoringRequest(&http.Request{
+		Method: http.MethodGet,
+		Header: http.Header{
+			"Authorization": []string{"Bearer wrong"},
+		},
+	})
+	if ok {
+		t.Fatal("expected invalid token to be rejected")
+	}
+	if status != http.StatusUnauthorized {
+		t.Fatalf("expected status %d, got %d", http.StatusUnauthorized, status)
+	}
+}
+
+func TestProxy_allowHTTP_NilConfig_Ugly(t *testing.T) {
+	p := &Proxy{}
+
+	status, ok := p.AllowMonitoringRequest(&http.Request{Method: http.MethodGet})
+	if ok {
+		t.Fatal("expected nil config request to be rejected")
+	}
+	if status != http.StatusServiceUnavailable {
+		t.Fatalf("expected status %d, got %d", http.StatusServiceUnavailable, status)
+	}
+}
+
+func TestProxy_startHTTP_Good(t *testing.T) {
+	p := &Proxy{
+		config: &Config{
+			HTTP: HTTPConfig{
+				Enabled: true,
+				Host:    "127.0.0.1",
+				Port:    0,
+			},
+		},
+		done: make(chan struct{}),
+	}
+
+	if ok := p.startMonitoringServer(); !ok {
+		t.Fatal("expected HTTP server to start on a free port")
+	}
+	p.Stop()
+}
+
+func TestProxy_startHTTP_NilConfig_Bad(t *testing.T) {
+	p := &Proxy{}
+
+	if ok := p.startMonitoringServer(); ok {
+		t.Fatal("expected nil config to skip HTTP server start")
+	}
+}
+
+func TestProxy_startHTTP_Bad(t *testing.T) {
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("listen on ephemeral port: %v", err)
+	}
+	defer listener.Close()
+
+	host, port, err := net.SplitHostPort(listener.Addr().String())
+	if err != nil {
+		t.Fatalf("split listener addr: %v", err)
+	}
+	portNum, err := strconv.Atoi(port)
+	if err != nil {
+		t.Fatalf("parse listener port: %v", err)
+	}
+
+	p := &Proxy{
+		config: &Config{
+			HTTP: HTTPConfig{
+				Enabled: true,
+				Host:    host,
+				Port:    uint16(portNum),
+			},
+		},
+		done: make(chan struct{}),
+	}
+
+	if ok := p.startMonitoringServer(); ok {
+		t.Fatal("expected HTTP server start to fail when the port is already in use")
+	}
+}
+
+func TestProxy_registerMonitoringRoute_MethodNotAllowed_Bad(t *testing.T) {
+	p := &Proxy{
+		config: &Config{
+			HTTP: HTTPConfig{
+				Restricted: true,
+			},
+		},
+	}
+
+	mux := http.NewServeMux()
+	p.registerMonitoringRoute(mux, "/1/summary", func() any { return map[string]string{"status": "ok"} })
+
+	request := httptest.NewRequest(http.MethodPost, "/1/summary", nil)
+	recorder := httptest.NewRecorder()
+	mux.ServeHTTP(recorder, request)
+
+	if recorder.Code != http.StatusMethodNotAllowed {
+		t.Fatalf("expected %d, got %d", http.StatusMethodNotAllowed, recorder.Code)
+	}
+	if got := recorder.Header().Get("Allow"); got != http.MethodGet {
+		t.Fatalf("expected Allow header %q, got %q", http.MethodGet, got)
+	}
+}
+
+func TestProxy_registerMonitoringRoute_Unauthorized_Ugly(t *testing.T) {
+	p := &Proxy{
+		config: &Config{
+			HTTP: HTTPConfig{
+				AccessToken: "secret",
+			},
+		},
+	}
+
+	mux := http.NewServeMux()
+	p.registerMonitoringRoute(mux, "/1/summary", func() any { return map[string]string{"status": "ok"} })
+
+	request := httptest.NewRequest(http.MethodGet, "/1/summary", nil)
+	recorder := httptest.NewRecorder()
+	mux.ServeHTTP(recorder, request)
+
+	if recorder.Code != http.StatusUnauthorized {
+		t.Fatalf("expected %d, got %d", http.StatusUnauthorized, recorder.Code)
+	}
+	if got := recorder.Header().Get("WWW-Authenticate"); got != "Bearer" {
+		t.Fatalf("expected WWW-Authenticate header %q, got %q", "Bearer", got)
+	}
+}

job.go

@@ -1,13 +1,15 @@
 package proxy
 
-// Job holds the current work unit received from a pool. Immutable once assigned.
+// Job holds one pool work unit and its metadata.
 //
 //	j := proxy.Job{
-//	    Blob:   "0707d5ef...b01",
+//	    Blob:   strings.Repeat("0", 160),
 //	    JobID:  "4BiGm3/RgGQzgkTI",
 //	    Target: "b88d0600",
 //	    Algo:   "cn/r",
 //	}
+//	_ = j.BlobWithFixedByte(0x2A)
+//	_ = j.DifficultyFromTarget()
 type Job struct {
 	Blob     string // hex-encoded block template (160 hex chars = 80 bytes)
 	JobID    string // pool-assigned identifier

job_test.go

@@ -5,7 +5,11 @@ import (
 	"testing"
 )
 
-func TestJob_BlobWithFixedByte(t *testing.T) {
+// TestJob_BlobWithFixedByte_Good verifies nonce patching on a full 160-char blob.
+//
+//	job := proxy.Job{Blob: strings.Repeat("0", 160)}
+//	result := job.BlobWithFixedByte(0x2A) // chars 78-79 become "2a"
+func TestJob_BlobWithFixedByte_Good(t *testing.T) {
 	job := Job{Blob: strings.Repeat("0", 160)}
 	got := job.BlobWithFixedByte(0x2A)
 	if len(got) != 160 {
@@ -16,9 +20,97 @@ func TestJob_BlobWithFixedByte(t *testing.T) {
 	}
 }
 
-func TestJob_DifficultyFromTarget(t *testing.T) {
-	job := Job{Target: "b88d0600"}
-	if got := job.DifficultyFromTarget(); got == 0 {
-		t.Fatalf("expected non-zero difficulty")
+// TestJob_BlobWithFixedByte_Bad verifies a short blob is returned unchanged.
+//
+//	job := proxy.Job{Blob: "0000"}
+//	result := job.BlobWithFixedByte(0x2A) // too short, returned as-is
+func TestJob_BlobWithFixedByte_Bad(t *testing.T) {
+	shortBlob := "0000"
+	job := Job{Blob: shortBlob}
+	got := job.BlobWithFixedByte(0x2A)
+	if got != shortBlob {
+		t.Fatalf("expected short blob to be returned unchanged, got %q", got)
+	}
+}
+
+// TestJob_BlobWithFixedByte_Ugly verifies fixedByte 0xFF renders as lowercase "ff".
+//
+//	job := proxy.Job{Blob: strings.Repeat("0", 160)}
+//	result := job.BlobWithFixedByte(0xFF) // chars 78-79 become "ff" (not "FF")
+func TestJob_BlobWithFixedByte_Ugly(t *testing.T) {
+	job := Job{Blob: strings.Repeat("0", 160)}
+	got := job.BlobWithFixedByte(0xFF)
+	if got[78:80] != "ff" {
+		t.Fatalf("expected lowercase 'ff', got %q", got[78:80])
+	}
+	if len(got) != 160 {
+		t.Fatalf("expected blob length preserved, got %d", len(got))
+	}
+}
+
+// TestJob_DifficultyFromTarget_Good verifies a known target converts to the expected difficulty.
+//
+//	job := proxy.Job{Target: "b88d0600"}
+//	diff := job.DifficultyFromTarget() // 10000
+func TestJob_DifficultyFromTarget_Good(t *testing.T) {
+	job := Job{Target: "b88d0600"}
+	if got := job.DifficultyFromTarget(); got != 10000 {
+		t.Fatalf("expected difficulty 10000, got %d", got)
+	}
+}
+
+// TestJob_DifficultyFromTarget_Bad verifies a zero target produces difficulty 0 without panic.
+//
+//	job := proxy.Job{Target: "00000000"}
+//	diff := job.DifficultyFromTarget() // 0 (no divide-by-zero)
+func TestJob_DifficultyFromTarget_Bad(t *testing.T) {
+	job := Job{Target: "00000000"}
+	if got := job.DifficultyFromTarget(); got != 0 {
+		t.Fatalf("expected difficulty 0 for zero target, got %d", got)
+	}
+}
+
+// TestJob_DifficultyFromTarget_Ugly verifies the maximum target "ffffffff" yields difficulty 1.
+//
+//	job := proxy.Job{Target: "ffffffff"}
+//	diff := job.DifficultyFromTarget() // 1
+func TestJob_DifficultyFromTarget_Ugly(t *testing.T) {
+	job := Job{Target: "ffffffff"}
+	if got := job.DifficultyFromTarget(); got != 1 {
+		t.Fatalf("expected minimum difficulty 1, got %d", got)
+	}
+}
+
+// TestJob_IsValid_Good verifies a job with blob and job ID is valid.
+//
+//	job := proxy.Job{Blob: "abc", JobID: "job-1"}
+//	job.IsValid() // true
+func TestJob_IsValid_Good(t *testing.T) {
+	job := Job{Blob: "abc", JobID: "job-1"}
+	if !job.IsValid() {
+		t.Fatalf("expected job with blob and job id to be valid")
+	}
+}
+
+// TestJob_IsValid_Bad verifies a job with empty blob or job ID is invalid.
+//
+//	job := proxy.Job{Blob: "", JobID: "job-1"}
+//	job.IsValid() // false
+func TestJob_IsValid_Bad(t *testing.T) {
+	if (Job{Blob: "", JobID: "job-1"}).IsValid() {
+		t.Fatalf("expected empty blob to be invalid")
+	}
+	if (Job{Blob: "abc", JobID: ""}).IsValid() {
+		t.Fatalf("expected empty job id to be invalid")
+	}
+}
+
+// TestJob_IsValid_Ugly verifies a zero-value job is invalid.
+//
+//	job := proxy.Job{}
+//	job.IsValid() // false
+func TestJob_IsValid_Ugly(t *testing.T) {
+	if (Job{}).IsValid() {
+		t.Fatalf("expected zero-value job to be invalid")
 	}
 }

log/access.go

@@ -15,11 +15,11 @@ import (
 // Line format (connect): 2026-04-04T12:00:00Z CONNECT  <ip>  <user>  <agent>
 // Line format (close):   2026-04-04T12:00:00Z CLOSE    <ip>  <user>  rx=<bytes>  tx=<bytes>
 //
-//	al, result := log.NewAccessLog("/var/log/proxy-access.log")
+//	al := log.NewAccessLog("/var/log/proxy-access.log")
 //	bus.Subscribe(proxy.EventLogin, al.OnLogin)
 //	bus.Subscribe(proxy.EventClose, al.OnClose)
 type AccessLog struct {
 	path string
 	mu   sync.Mutex
-	f    *os.File
+	file *os.File
 }

log/impl.go

@@ -10,32 +10,79 @@ import (
 )
 
 // NewAccessLog creates an append-only access log.
+//
+//	al := log.NewAccessLog("/var/log/proxy-access.log")
+//	defer al.Close()
 func NewAccessLog(path string) *AccessLog {
 	return &AccessLog{path: path}
 }
 
-// OnLogin writes a CONNECT line.
+// Close releases the underlying file handle if the log has been opened.
+//
+//	al := log.NewAccessLog("/var/log/proxy-access.log")
+//	defer al.Close()
+func (l *AccessLog) Close() {
+	if l == nil {
+		return
+	}
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if l.file != nil {
+		_ = l.file.Close()
+		l.file = nil
+	}
+}
+
+// OnLogin writes a connect line such as:
+//
+//	al.OnLogin(proxy.Event{Miner: &proxy.Miner{}})
+//	// 2026-04-04T12:00:00Z CONNECT  10.0.0.1  WALLET  XMRig/6.21.0
 func (l *AccessLog) OnLogin(e proxy.Event) {
 	if l == nil || e.Miner == nil {
 		return
 	}
-	l.writeLine("CONNECT", e.Miner.IP(), e.Miner.User(), e.Miner.Agent(), 0, 0)
+	l.writeConnectLine(e.Miner.IP(), e.Miner.User(), e.Miner.Agent())
 }
 
-// OnClose writes a CLOSE line with byte counts.
+// OnClose writes a close line such as:
+//
+//	al.OnClose(proxy.Event{Miner: &proxy.Miner{}})
+//	// 2026-04-04T12:00:00Z CLOSE  10.0.0.1  WALLET  rx=512  tx=4096
 func (l *AccessLog) OnClose(e proxy.Event) {
 	if l == nil || e.Miner == nil {
 		return
 	}
-	l.writeLine("CLOSE", e.Miner.IP(), e.Miner.User(), "", e.Miner.RX(), e.Miner.TX())
+	l.writeCloseLine(e.Miner.IP(), e.Miner.User(), e.Miner.RX(), e.Miner.TX())
 }
 
 // NewShareLog creates an append-only share log.
+//
+//	sl := log.NewShareLog("/var/log/proxy-shares.log")
+//	defer sl.Close()
 func NewShareLog(path string) *ShareLog {
 	return &ShareLog{path: path}
 }
 
-// OnAccept writes an ACCEPT line.
+// Close releases the underlying file handle if the log has been opened.
+//
+//	sl := log.NewShareLog("/var/log/proxy-shares.log")
+//	defer sl.Close()
+func (l *ShareLog) Close() {
+	if l == nil {
+		return
+	}
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if l.file != nil {
+		_ = l.file.Close()
+		l.file = nil
+	}
+}
+
+// OnAccept writes an accept line such as:
+//
+//	sl.OnAccept(proxy.Event{Miner: &proxy.Miner{}, Diff: 100000, Latency: 82})
+//	// 2026-04-04T12:00:00Z ACCEPT  WALLET  diff=100000  latency=82ms
 func (l *ShareLog) OnAccept(e proxy.Event) {
 	if l == nil || e.Miner == nil {
 		return
@@ -43,7 +90,10 @@ func (l *ShareLog) OnAccept(e proxy.Event) {
 	l.writeAcceptLine(e.Miner.User(), e.Diff, uint64(e.Latency))
 }
 
-// OnReject writes a REJECT line.
+// OnReject writes a reject line such as:
+//
+//	sl.OnReject(proxy.Event{Miner: &proxy.Miner{}, Error: "Invalid nonce"})
+//	// 2026-04-04T12:00:00Z REJECT  WALLET  reason="Invalid nonce"
 func (l *ShareLog) OnReject(e proxy.Event) {
 	if l == nil || e.Miner == nil {
 		return
@@ -51,38 +101,52 @@ func (l *ShareLog) OnReject(e proxy.Event) {
 	l.writeRejectLine(e.Miner.User(), e.Error)
 }
 
-func (l *AccessLog) writeLine(kind, ip, user, agent string, rx, tx uint64) {
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	if err := l.ensureFile(); err != nil {
+func (accessLog *AccessLog) writeConnectLine(ip, user, agent string) {
+	accessLog.mu.Lock()
+	defer accessLog.mu.Unlock()
+	if err := accessLog.ensureFile(); err != nil {
 		return
 	}
 	var builder strings.Builder
 	builder.WriteString(time.Now().UTC().Format(time.RFC3339))
 	builder.WriteByte(' ')
-	builder.WriteString(kind)
+	builder.WriteString("CONNECT")
 	builder.WriteString("  ")
 	builder.WriteString(ip)
 	builder.WriteString("  ")
 	builder.WriteString(user)
-	if agent != "" {
-		builder.WriteString("  ")
-		builder.WriteString(agent)
-	}
-	if rx > 0 || tx > 0 {
-		builder.WriteString("  rx=")
-		builder.WriteString(strconv.FormatUint(rx, 10))
-		builder.WriteString("  tx=")
-		builder.WriteString(strconv.FormatUint(tx, 10))
-	}
+	builder.WriteString("  ")
+	builder.WriteString(agent)
 	builder.WriteByte('\n')
-	_, _ = l.f.WriteString(builder.String())
+	_, _ = accessLog.file.WriteString(builder.String())
 }
 
-func (l *ShareLog) writeAcceptLine(user string, diff uint64, latency uint64) {
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	if err := l.ensureFile(); err != nil {
+func (accessLog *AccessLog) writeCloseLine(ip, user string, rx, tx uint64) {
+	accessLog.mu.Lock()
+	defer accessLog.mu.Unlock()
+	if err := accessLog.ensureFile(); err != nil {
+		return
+	}
+	var builder strings.Builder
+	builder.WriteString(time.Now().UTC().Format(time.RFC3339))
+	builder.WriteByte(' ')
+	builder.WriteString("CLOSE")
+	builder.WriteString("  ")
+	builder.WriteString(ip)
+	builder.WriteString("  ")
+	builder.WriteString(user)
+	builder.WriteString("  rx=")
+	builder.WriteString(strconv.FormatUint(rx, 10))
+	builder.WriteString("  tx=")
+	builder.WriteString(strconv.FormatUint(tx, 10))
+	builder.WriteByte('\n')
+	_, _ = accessLog.file.WriteString(builder.String())
+}
+
+func (shareLog *ShareLog) writeAcceptLine(user string, diff uint64, latency uint64) {
+	shareLog.mu.Lock()
+	defer shareLog.mu.Unlock()
+	if err := shareLog.ensureFile(); err != nil {
 		return
 	}
 	var builder strings.Builder
@@ -96,13 +160,13 @@ func (l *ShareLog) writeAcceptLine(user string, diff uint64, latency uint64) {
 	builder.WriteString(strconv.FormatUint(latency, 10))
 	builder.WriteString("ms")
 	builder.WriteByte('\n')
-	_, _ = l.f.WriteString(builder.String())
+	_, _ = shareLog.file.WriteString(builder.String())
 }
 
-func (l *ShareLog) writeRejectLine(user, reason string) {
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	if err := l.ensureFile(); err != nil {
+func (shareLog *ShareLog) writeRejectLine(user, reason string) {
+	shareLog.mu.Lock()
+	defer shareLog.mu.Unlock()
+	if err := shareLog.ensureFile(); err != nil {
 		return
 	}
 	var builder strings.Builder
@@ -112,29 +176,29 @@ func (l *ShareLog) writeRejectLine(user, reason string) {
 	builder.WriteString("  reason=\"")
 	builder.WriteString(reason)
 	builder.WriteString("\"\n")
-	_, _ = l.f.WriteString(builder.String())
+	_, _ = shareLog.file.WriteString(builder.String())
 }
 
-func (l *AccessLog) ensureFile() error {
-	if l.f != nil {
+func (accessLog *AccessLog) ensureFile() error {
+	if accessLog.file != nil {
 		return nil
 	}
-	f, err := os.OpenFile(l.path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
+	f, err := os.OpenFile(accessLog.path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
 	if err != nil {
 		return err
 	}
-	l.f = f
+	accessLog.file = f
 	return nil
 }
 
-func (l *ShareLog) ensureFile() error {
-	if l.f != nil {
+func (shareLog *ShareLog) ensureFile() error {
+	if shareLog.file != nil {
 		return nil
 	}
-	f, err := os.OpenFile(l.path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
+	f, err := os.OpenFile(shareLog.path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
 	if err != nil {
 		return err
 	}
-	l.f = f
+	shareLog.file = f
 	return nil
 }

log/impl_test.go

@@ -0,0 +1,341 @@
+package log
+
+import (
+	"net"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+
+	"dappco.re/go/proxy"
+)
+
+// TestAccessLog_OnLogin_Good verifies a CONNECT line is written with the expected columns.
+//
+//	al := log.NewAccessLog("/tmp/test-access.log")
+//	al.OnLogin(proxy.Event{Miner: miner}) // writes "CONNECT  10.0.0.1  WALLET  XMRig/6.21.0"
+func TestAccessLog_OnLogin_Good(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "access.log")
+	al := NewAccessLog(path)
+	defer al.Close()
+
+	miner := newTestMiner(t)
+	al.OnLogin(proxy.Event{Miner: miner})
+	al.Close()
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("expected log file to exist: %v", err)
+	}
+	line := strings.TrimSpace(string(data))
+	if !strings.Contains(line, "CONNECT") {
+		t.Fatalf("expected CONNECT in log line, got %q", line)
+	}
+}
+
+// TestAccessLog_OnLogin_Bad verifies a nil miner event does not panic or write anything.
+//
+//	al := log.NewAccessLog("/tmp/test-access.log")
+//	al.OnLogin(proxy.Event{Miner: nil}) // no-op
+func TestAccessLog_OnLogin_Bad(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "access.log")
+	al := NewAccessLog(path)
+	defer al.Close()
+
+	al.OnLogin(proxy.Event{Miner: nil})
+	al.Close()
+
+	if _, err := os.Stat(path); err == nil {
+		data, _ := os.ReadFile(path)
+		if len(data) > 0 {
+			t.Fatalf("expected no output for nil miner, got %q", string(data))
+		}
+	}
+}
+
+// TestAccessLog_OnLogin_Ugly verifies a nil AccessLog does not panic.
+//
+//	var al *log.AccessLog
+//	al.OnLogin(proxy.Event{Miner: miner}) // no-op, no panic
+func TestAccessLog_OnLogin_Ugly(t *testing.T) {
+	var al *AccessLog
+	miner := newTestMiner(t)
+	al.OnLogin(proxy.Event{Miner: miner})
+}
+
+// TestAccessLog_OnClose_Good verifies a CLOSE line includes rx and tx byte counts.
+//
+//	al := log.NewAccessLog("/tmp/test-access.log")
+//	al.OnClose(proxy.Event{Miner: miner}) // writes "CLOSE  <ip>  <user>  rx=0  tx=0"
+func TestAccessLog_OnClose_Good(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "access.log")
+	al := NewAccessLog(path)
+	defer al.Close()
+
+	miner := newTestMiner(t)
+	al.OnClose(proxy.Event{Miner: miner})
+	al.Close()
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("expected log file to exist: %v", err)
+	}
+	line := strings.TrimSpace(string(data))
+	if !strings.Contains(line, "CLOSE") {
+		t.Fatalf("expected CLOSE in log line, got %q", line)
+	}
+	if !strings.Contains(line, "rx=") {
+		t.Fatalf("expected rx= in log line, got %q", line)
+	}
+	if !strings.Contains(line, "tx=") {
+		t.Fatalf("expected tx= in log line, got %q", line)
+	}
+}
+
+// TestAccessLog_OnClose_Bad verifies a nil miner close event produces no output.
+//
+//	al := log.NewAccessLog("/tmp/test-access.log")
+//	al.OnClose(proxy.Event{Miner: nil}) // no-op
+func TestAccessLog_OnClose_Bad(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "access.log")
+	al := NewAccessLog(path)
+	defer al.Close()
+
+	al.OnClose(proxy.Event{Miner: nil})
+	al.Close()
+
+	if _, err := os.Stat(path); err == nil {
+		data, _ := os.ReadFile(path)
+		if len(data) > 0 {
+			t.Fatalf("expected no output for nil miner, got %q", string(data))
+		}
+	}
+}
+
+// TestAccessLog_OnClose_Ugly verifies close on an empty-path log is a no-op.
+//
+//	al := log.NewAccessLog("")
+//	al.OnClose(proxy.Event{Miner: miner}) // no-op, empty path
+func TestAccessLog_OnClose_Ugly(t *testing.T) {
+	al := NewAccessLog("")
+	defer al.Close()
+
+	miner := newTestMiner(t)
+	al.OnClose(proxy.Event{Miner: miner})
+}
+
+// TestShareLog_OnAccept_Good verifies an ACCEPT line is written with diff and latency.
+//
+//	sl := log.NewShareLog("/tmp/test-shares.log")
+//	sl.OnAccept(proxy.Event{Miner: miner, Diff: 100000, Latency: 82})
+func TestShareLog_OnAccept_Good(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "shares.log")
+	sl := NewShareLog(path)
+	defer sl.Close()
+
+	miner := newTestMiner(t)
+	sl.OnAccept(proxy.Event{Miner: miner, Diff: 100000, Latency: 82})
+	sl.Close()
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("expected log file to exist: %v", err)
+	}
+	line := strings.TrimSpace(string(data))
+	if !strings.Contains(line, "ACCEPT") {
+		t.Fatalf("expected ACCEPT in log line, got %q", line)
+	}
+	if !strings.Contains(line, "diff=100000") {
+		t.Fatalf("expected diff=100000 in log line, got %q", line)
+	}
+	if !strings.Contains(line, "latency=82ms") {
+		t.Fatalf("expected latency=82ms in log line, got %q", line)
+	}
+}
+
+// TestShareLog_OnAccept_Bad verifies a nil miner accept event produces no output.
+//
+//	sl := log.NewShareLog("/tmp/test-shares.log")
+//	sl.OnAccept(proxy.Event{Miner: nil}) // no-op
+func TestShareLog_OnAccept_Bad(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "shares.log")
+	sl := NewShareLog(path)
+	defer sl.Close()
+
+	sl.OnAccept(proxy.Event{Miner: nil, Diff: 100000})
+	sl.Close()
+
+	if _, err := os.Stat(path); err == nil {
+		data, _ := os.ReadFile(path)
+		if len(data) > 0 {
+			t.Fatalf("expected no output for nil miner, got %q", string(data))
+		}
+	}
+}
+
+// TestShareLog_OnAccept_Ugly verifies a nil ShareLog does not panic.
+//
+//	var sl *log.ShareLog
+//	sl.OnAccept(proxy.Event{Miner: miner}) // no-op, no panic
+func TestShareLog_OnAccept_Ugly(t *testing.T) {
+	var sl *ShareLog
+	miner := newTestMiner(t)
+	sl.OnAccept(proxy.Event{Miner: miner, Diff: 100000})
+}
+
+// TestShareLog_OnReject_Good verifies a REJECT line is written with the rejection reason.
+//
+//	sl := log.NewShareLog("/tmp/test-shares.log")
+//	sl.OnReject(proxy.Event{Miner: miner, Error: "Low difficulty share"})
+func TestShareLog_OnReject_Good(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "shares.log")
+	sl := NewShareLog(path)
+	defer sl.Close()
+
+	miner := newTestMiner(t)
+	sl.OnReject(proxy.Event{Miner: miner, Error: "Low difficulty share"})
+	sl.Close()
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("expected log file to exist: %v", err)
+	}
+	line := strings.TrimSpace(string(data))
+	if !strings.Contains(line, "REJECT") {
+		t.Fatalf("expected REJECT in log line, got %q", line)
+	}
+	if !strings.Contains(line, "Low difficulty share") {
+		t.Fatalf("expected rejection reason in log line, got %q", line)
+	}
+}
+
+// TestShareLog_OnReject_Bad verifies a nil miner reject event produces no output.
+//
+//	sl := log.NewShareLog("/tmp/test-shares.log")
+//	sl.OnReject(proxy.Event{Miner: nil}) // no-op
+func TestShareLog_OnReject_Bad(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "shares.log")
+	sl := NewShareLog(path)
+	defer sl.Close()
+
+	sl.OnReject(proxy.Event{Miner: nil, Error: "Low difficulty share"})
+	sl.Close()
+
+	if _, err := os.Stat(path); err == nil {
+		data, _ := os.ReadFile(path)
+		if len(data) > 0 {
+			t.Fatalf("expected no output for nil miner, got %q", string(data))
+		}
+	}
+}
+
+// TestShareLog_OnReject_Ugly verifies an empty-path ShareLog silently discards the reject line.
+//
+//	sl := log.NewShareLog("")
+//	sl.OnReject(proxy.Event{Miner: miner, Error: "reason"}) // no-op, empty path
+func TestShareLog_OnReject_Ugly(t *testing.T) {
+	sl := NewShareLog("")
+	defer sl.Close()
+
+	miner := newTestMiner(t)
+	sl.OnReject(proxy.Event{Miner: miner, Error: "reason"})
+}
+
+// TestAccessLog_Close_Good verifies Close releases the file handle and is safe to call twice.
+//
+//	al := log.NewAccessLog("/tmp/test-access.log")
+//	al.OnLogin(proxy.Event{Miner: miner})
+//	al.Close()
+//	al.Close() // double close is safe
+func TestAccessLog_Close_Good(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "access.log")
+	al := NewAccessLog(path)
+
+	miner := newTestMiner(t)
+	al.OnLogin(proxy.Event{Miner: miner})
+	al.Close()
+	al.Close()
+}
+
+// TestAccessLog_Close_Bad verifies Close on a nil AccessLog does not panic.
+//
+//	var al *log.AccessLog
+//	al.Close() // no-op, no panic
+func TestAccessLog_Close_Bad(t *testing.T) {
+	var al *AccessLog
+	al.Close()
+}
+
+// TestAccessLog_Close_Ugly verifies Close on a never-opened log does not panic.
+//
+//	al := log.NewAccessLog("/nonexistent/dir/access.log")
+//	al.Close() // no file was ever opened
+func TestAccessLog_Close_Ugly(t *testing.T) {
+	al := NewAccessLog("/nonexistent/dir/access.log")
+	al.Close()
+}
+
+// TestShareLog_Close_Good verifies Close releases the file handle and is safe to call twice.
+//
+//	sl := log.NewShareLog("/tmp/test-shares.log")
+//	sl.OnAccept(proxy.Event{Miner: miner, Diff: 1000})
+//	sl.Close()
+//	sl.Close() // double close is safe
+func TestShareLog_Close_Good(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "shares.log")
+	sl := NewShareLog(path)
+
+	miner := newTestMiner(t)
+	sl.OnAccept(proxy.Event{Miner: miner, Diff: 1000})
+	sl.Close()
+	sl.Close()
+}
+
+// TestShareLog_Close_Bad verifies Close on a nil ShareLog does not panic.
+//
+//	var sl *log.ShareLog
+//	sl.Close() // no-op, no panic
+func TestShareLog_Close_Bad(t *testing.T) {
+	var sl *ShareLog
+	sl.Close()
+}
+
+// TestShareLog_Close_Ugly verifies Close on a never-opened log does not panic.
+//
+//	sl := log.NewShareLog("/nonexistent/dir/shares.log")
+//	sl.Close() // no file was ever opened
+func TestShareLog_Close_Ugly(t *testing.T) {
+	sl := NewShareLog("/nonexistent/dir/shares.log")
+	sl.Close()
+}
+
+// newTestMiner creates a minimal miner for log testing using a net.Pipe connection.
+func newTestMiner(t *testing.T) *proxy.Miner {
+	t.Helper()
+	client, server := net.Pipe()
+	t.Cleanup(func() {
+		_ = client.Close()
+		_ = server.Close()
+	})
+	miner := proxy.NewMiner(client, 3333, nil)
+	miner.SetID(1)
+	return miner
+}
+
+// pipeAddr satisfies the net.Addr interface for pipe-based test connections.
+type pipeAddr struct{}
+
+func (a pipeAddr) Network() string { return "pipe" }
+func (a pipeAddr) String() string  { return "pipe" }
+
+// pipeConn wraps an os.Pipe as a net.Conn for tests that need a closeable socket.
+type pipeConn struct {
+	*os.File
+}
+
+func (p *pipeConn) RemoteAddr() net.Addr                { return pipeAddr{} }
+func (p *pipeConn) LocalAddr() net.Addr                 { return pipeAddr{} }
+func (p *pipeConn) SetDeadline(_ time.Time) error       { return nil }
+func (p *pipeConn) SetReadDeadline(_ time.Time) error   { return nil }
+func (p *pipeConn) SetWriteDeadline(_ time.Time) error  { return nil }

log/share.go

@@ -16,5 +16,5 @@ import (
 type ShareLog struct {
 	path string
 	mu   sync.Mutex
-	f    *os.File
+	file *os.File
 }

miner.go

@@ -25,35 +25,41 @@ const (
 //	m := proxy.NewMiner(conn, 3333, nil)
 //	m.Start()
 type Miner struct {
-	id             int64  // monotonically increasing per-process; atomic assignment
-	rpcID          string // UUID v4 sent to miner as session id
-	state          MinerState
-	extAlgo        bool   // miner sent algo list in login params
-	extNH          bool   // NiceHash mode active (fixed byte splitting)
-	ip             string // remote IP (without port, for logging)
-	localPort      uint16
-	user           string // login params.login (wallet address), custom diff suffix stripped
-	password       string // login params.pass
-	agent          string // login params.agent
-	rigID          string // login params.rigid (optional extension)
-	fixedByte      uint8  // NiceHash slot index (0-255)
-	mapperID       int64  // which NonceMapper owns this miner; -1 = unassigned
-	routeID        int64  // SimpleMapper ID in simple mode; -1 = unassigned
-	customDiff     uint64 // 0 = use pool diff; non-zero = cap diff to this value
-	accessPassword string
-	globalDiff     uint64
-	diff           uint64 // last difficulty sent to this miner from the pool
-	rx             uint64 // bytes received from miner
-	tx             uint64 // bytes sent from miner
-	currentJob     Job
-	connectedAt    time.Time
-	lastActivityAt time.Time
-	conn           net.Conn
-	tlsConn        *tls.Conn   // nil if plain TCP
-	sendMu         sync.Mutex  // serialises writes to conn
-	buf            [16384]byte // per-miner send buffer; avoids per-write allocations
-	onLogin        func(*Miner)
-	onSubmit       func(*Miner, *SubmitEvent)
-	onClose        func(*Miner)
-	closeOnce      sync.Once
+	id                  int64  // monotonically increasing per-process; atomic assignment
+	rpcID               string // UUID v4 sent to miner as session id
+	state               MinerState
+	extAlgo             bool // miner sent algo list in login params
+	loginAlgos          []string
+	extNH               bool   // NiceHash mode active (fixed byte splitting)
+	algoEnabled         bool   // proxy is configured to negotiate the algo extension
+	ip                  string // remote IP (without port, for logging)
+	remoteAddr          string
+	localPort           uint16
+	user                string // login params.login (wallet address), custom diff suffix stripped
+	password            string // login params.pass
+	agent               string // login params.agent
+	rigID               string // login params.rigid (optional extension)
+	fixedByte           uint8  // NiceHash slot index (0-255)
+	mapperID            int64  // which NonceMapper owns this miner; -1 = unassigned
+	routeID             int64  // SimpleMapper ID in simple mode; -1 = unassigned
+	customDiff          uint64 // 0 = use pool diff; non-zero = cap diff to this value
+	customDiffResolved  bool
+	customDiffFromLogin bool
+	accessPassword      string
+	globalDiff          uint64
+	diff                uint64 // last difficulty sent to this miner from the pool
+	rx                  uint64 // bytes received from miner
+	tx                  uint64 // bytes sent from miner
+	currentJob          Job
+	connectedAt         time.Time
+	lastActivityAt      time.Time
+	conn                net.Conn
+	tlsConn             *tls.Conn   // nil if plain TCP
+	sendMu              sync.Mutex  // serialises writes to conn
+	buf                 [16384]byte // per-miner send buffer; avoids per-write allocations
+	onLogin             func(*Miner)
+	onLoginReady        func(*Miner)
+	onSubmit            func(*Miner, *SubmitEvent)
+	onClose             func(*Miner)
+	closeOnce           sync.Once
 }

miner_login_test.go

@@ -0,0 +1,467 @@
+package proxy
+
+import (
+	"bufio"
+	"encoding/json"
+	"net"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestMiner_HandleLogin_Good(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := NewMiner(minerConn, 3333, nil)
+	miner.algoEnabled = true
+	miner.extNH = true
+	miner.fixedByte = 0x2a
+	miner.onLogin = func(m *Miner) {
+		m.SetMapperID(1)
+	}
+	miner.currentJob = Job{
+		Blob:     strings.Repeat("0", 160),
+		JobID:    "job-1",
+		Target:   "b88d0600",
+		Algo:     "cn/r",
+		Height:   7,
+		SeedHash: "seed",
+	}
+
+	params, err := json.Marshal(loginParams{
+		Login: "wallet",
+		Pass:  "x",
+		Agent: "xmrig",
+		Algo:  []string{"cn/r"},
+		RigID: "rig-1",
+	})
+	if err != nil {
+		t.Fatalf("marshal login params: %v", err)
+	}
+
+	done := make(chan struct{})
+	go func() {
+		miner.handleLogin(stratumRequest{ID: 1, Method: "login", Params: params})
+		close(done)
+	}()
+
+	line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read login response: %v", err)
+	}
+	<-done
+
+	var payload struct {
+		Error  json.RawMessage `json:"error"`
+		Result struct {
+			ID         string         `json:"id"`
+			Status     string         `json:"status"`
+			Extensions []string       `json:"extensions"`
+			Job        map[string]any `json:"job"`
+		} `json:"result"`
+	}
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal login response: %v", err)
+	}
+
+	if string(payload.Error) != "null" {
+		t.Fatalf("expected login response error to be null, got %s", string(payload.Error))
+	}
+	if payload.Result.Status != "OK" {
+		t.Fatalf("expected login success, got %q", payload.Result.Status)
+	}
+	if payload.Result.ID == "" {
+		t.Fatalf("expected rpc id in login response")
+	}
+	if len(payload.Result.Extensions) != 1 || payload.Result.Extensions[0] != "algo" {
+		t.Fatalf("expected algo extension, got %#v", payload.Result.Extensions)
+	}
+	if got := miner.LoginAlgos(); len(got) != 1 || got[0] != "cn/r" {
+		t.Fatalf("expected login algo list to be stored, got %#v", got)
+	}
+	if got := payload.Result.Job["job_id"]; got != "job-1" {
+		t.Fatalf("expected embedded job, got %#v", got)
+	}
+	if got := payload.Result.Job["algo"]; got != "cn/r" {
+		t.Fatalf("expected embedded algo, got %#v", got)
+	}
+	blob, _ := payload.Result.Job["blob"].(string)
+	if blob[78:80] != "2a" {
+		t.Fatalf("expected fixed-byte patched blob, got %q", blob[78:80])
+	}
+	if miner.State() != MinerStateReady {
+		t.Fatalf("expected miner ready after login reply with job, got %d", miner.State())
+	}
+}
+
+func TestProxy_New_Watch_Good(t *testing.T) {
+	cfg := &Config{
+		Mode:       "nicehash",
+		Workers:    WorkersByRigID,
+		Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		Watch:      true,
+		configPath: "/tmp/proxy.json",
+	}
+
+	proxyInstance, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected valid proxy, got error: %v", result.Error)
+	}
+	if proxyInstance.watcher == nil {
+		t.Fatalf("expected config watcher when watch is enabled and source path is known")
+	}
+}
+
+func TestMiner_HandleLogin_Ugly(t *testing.T) {
+	for i := 0; i < 256; i++ {
+		miner := &Miner{}
+		miner.SetID(int64(i + 1))
+		miner.SetMapperID(int64(i + 1))
+	}
+
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+	defer clientConn.Close()
+
+	miner := NewMiner(serverConn, 3333, nil)
+	miner.extNH = true
+	miner.onLogin = func(*Miner) {}
+
+	params, err := json.Marshal(loginParams{
+		Login: "wallet",
+		Pass:  "x",
+	})
+	if err != nil {
+		t.Fatalf("marshal login params: %v", err)
+	}
+
+	done := make(chan []byte, 1)
+	go func() {
+		line, readErr := bufio.NewReader(clientConn).ReadBytes('\n')
+		if readErr != nil {
+			done <- nil
+			return
+		}
+		done <- line
+	}()
+
+	miner.handleLogin(stratumRequest{ID: 2, Method: "login", Params: params})
+
+	line := <-done
+	if line == nil {
+		t.Fatal("expected login rejection response")
+	}
+
+	var payload struct {
+		Error struct {
+			Message string `json:"message"`
+		} `json:"error"`
+		Result map[string]any `json:"result"`
+	}
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal login response: %v", err)
+	}
+	if payload.Error.Message != "Proxy is full, try again later" {
+		t.Fatalf("expected full-table error, got %q", payload.Error.Message)
+	}
+	if payload.Result != nil {
+		t.Fatalf("expected no login success payload, got %#v", payload.Result)
+	}
+	if miner.MapperID() != -1 {
+		t.Fatalf("expected rejected miner to remain unassigned, got mapper %d", miner.MapperID())
+	}
+}
+
+func TestMiner_HandleLogin_FailedAssignmentDoesNotDispatchLoginEvent(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	proxyInstance := &Proxy{
+		config: &Config{
+			Mode:    "nicehash",
+			Workers: WorkersByUser,
+			Bind:    []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+			Pools:   []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		},
+		events:  NewEventBus(),
+		stats:   NewStats(),
+		workers: NewWorkers(WorkersByUser, nil),
+		miners:  make(map[int64]*Miner),
+	}
+	proxyInstance.events.Subscribe(EventLogin, proxyInstance.stats.OnLogin)
+	proxyInstance.workers.bindEvents(proxyInstance.events)
+
+	miner := NewMiner(minerConn, 3333, nil)
+	miner.extNH = true
+	miner.onLogin = func(*Miner) {}
+	miner.onLoginReady = func(m *Miner) {
+		proxyInstance.events.Dispatch(Event{Type: EventLogin, Miner: m})
+	}
+	proxyInstance.miners[miner.ID()] = miner
+
+	params, err := json.Marshal(loginParams{
+		Login: "wallet",
+		Pass:  "x",
+	})
+	if err != nil {
+		t.Fatalf("marshal login params: %v", err)
+	}
+
+	go miner.handleLogin(stratumRequest{ID: 12, Method: "login", Params: params})
+
+	line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read login rejection: %v", err)
+	}
+
+	var payload struct {
+		Error struct {
+			Message string `json:"message"`
+		} `json:"error"`
+	}
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal login rejection: %v", err)
+	}
+	if payload.Error.Message != "Proxy is full, try again later" {
+		t.Fatalf("expected full-table rejection, got %q", payload.Error.Message)
+	}
+	if now, max := proxyInstance.MinerCount(); now != 0 || max != 0 {
+		t.Fatalf("expected failed login not to affect miner counts, got now=%d max=%d", now, max)
+	}
+	if records := proxyInstance.WorkerRecords(); len(records) != 0 {
+		t.Fatalf("expected failed login not to create worker records, got %d", len(records))
+	}
+}
+
+func TestMiner_HandleLogin_CustomDiffCap_Good(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := NewMiner(minerConn, 3333, nil)
+	miner.onLogin = func(m *Miner) {
+		m.SetRouteID(1)
+		m.customDiff = 5000
+	}
+	miner.currentJob = Job{
+		Blob:   strings.Repeat("0", 160),
+		JobID:  "job-1",
+		Target: "01000000",
+	}
+
+	params, err := json.Marshal(loginParams{
+		Login: "wallet",
+		Pass:  "x",
+	})
+	if err != nil {
+		t.Fatalf("marshal login params: %v", err)
+	}
+
+	go miner.handleLogin(stratumRequest{ID: 3, Method: "login", Params: params})
+
+	line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read login response: %v", err)
+	}
+
+	var payload struct {
+		Result struct {
+			Job struct {
+				Target string `json:"target"`
+			} `json:"job"`
+		} `json:"result"`
+	}
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal login response: %v", err)
+	}
+
+	originalDiff := miner.currentJob.DifficultyFromTarget()
+	cappedDiff := Job{Target: payload.Result.Job.Target}.DifficultyFromTarget()
+	if cappedDiff == 0 || cappedDiff > 5000 {
+		t.Fatalf("expected capped difficulty at or below 5000, got %d", cappedDiff)
+	}
+	if cappedDiff >= originalDiff {
+		t.Fatalf("expected lowered target difficulty below %d, got %d", originalDiff, cappedDiff)
+	}
+	if miner.diff != cappedDiff {
+		t.Fatalf("expected miner diff %d, got %d", cappedDiff, miner.diff)
+	}
+}
+
+func TestMiner_HandleLogin_CustomDiffSuffix_Good(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := NewMiner(minerConn, 3333, nil)
+	miner.onLogin = func(m *Miner) {
+		m.SetRouteID(1)
+	}
+
+	params, err := json.Marshal(loginParams{
+		Login: "wallet+50000",
+		Pass:  "x",
+	})
+	if err != nil {
+		t.Fatalf("marshal login params: %v", err)
+	}
+
+	go miner.handleLogin(stratumRequest{ID: 4, Method: "login", Params: params})
+
+	line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read login response: %v", err)
+	}
+
+	var payload struct {
+		Result struct {
+			Status string `json:"status"`
+		} `json:"result"`
+	}
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal login response: %v", err)
+	}
+	if payload.Result.Status != "OK" {
+		t.Fatalf("expected login success, got %q", payload.Result.Status)
+	}
+	if got := miner.User(); got != "wallet" {
+		t.Fatalf("expected stripped wallet name, got %q", got)
+	}
+	if got := miner.customDiff; got != 50000 {
+		t.Fatalf("expected custom diff 50000, got %d", got)
+	}
+}
+
+func TestMiner_HandleKeepalived_Good(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := NewMiner(minerConn, 3333, nil)
+
+	done := make(chan struct{})
+	go func() {
+		miner.handleKeepalived(stratumRequest{ID: 9, Method: "keepalived"})
+		close(done)
+	}()
+
+	line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read keepalived response: %v", err)
+	}
+	<-done
+
+	var payload map[string]json.RawMessage
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal keepalived response: %v", err)
+	}
+	if _, ok := payload["error"]; !ok {
+		t.Fatalf("expected keepalived response to include error field, got %s", string(line))
+	}
+	if string(payload["error"]) != "null" {
+		t.Fatalf("expected keepalived response error to be null, got %s", string(payload["error"]))
+	}
+	var result struct {
+		Status string `json:"status"`
+	}
+	if err := json.Unmarshal(payload["result"], &result); err != nil {
+		t.Fatalf("unmarshal keepalived result: %v", err)
+	}
+	if result.Status != "KEEPALIVED" {
+		t.Fatalf("expected KEEPALIVED status, got %q", result.Status)
+	}
+}
+
+func TestMiner_ReadLoop_RFCLineLimit_Good(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := NewMiner(minerConn, 3333, nil)
+	miner.onLogin = func(m *Miner) {
+		m.SetRouteID(1)
+	}
+	miner.Start()
+
+	params, err := json.Marshal(loginParams{
+		Login: "wallet",
+		Pass:  "x",
+		Agent: strings.Repeat("a", 5000),
+	})
+	if err != nil {
+		t.Fatalf("marshal login params: %v", err)
+	}
+	request, err := json.Marshal(stratumRequest{ID: 4, Method: "login", Params: params})
+	if err != nil {
+		t.Fatalf("marshal request: %v", err)
+	}
+	if len(request) >= maxStratumLineLength {
+		t.Fatalf("expected test request below RFC limit, got %d bytes", len(request))
+	}
+
+	if _, err := clientConn.Write(append(request, '\n')); err != nil {
+		t.Fatalf("write login request: %v", err)
+	}
+	_ = clientConn.SetReadDeadline(time.Now().Add(time.Second))
+	line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read login response: %v", err)
+	}
+	if len(line) == 0 {
+		t.Fatal("expected login response for request under RFC limit")
+	}
+}
+
+func TestMiner_ReadLoop_RFCLineLimit_Ugly(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := NewMiner(minerConn, 3333, nil)
+	miner.Start()
+
+	params, err := json.Marshal(loginParams{
+		Login: "wallet",
+		Pass:  "x",
+		Agent: strings.Repeat("b", maxStratumLineLength),
+	})
+	if err != nil {
+		t.Fatalf("marshal login params: %v", err)
+	}
+	request, err := json.Marshal(stratumRequest{ID: 5, Method: "login", Params: params})
+	if err != nil {
+		t.Fatalf("marshal request: %v", err)
+	}
+	if len(request) <= maxStratumLineLength {
+		t.Fatalf("expected test request above RFC limit, got %d bytes", len(request))
+	}
+
+	writeDone := make(chan error, 1)
+	go func() {
+		_, writeErr := clientConn.Write(append(request, '\n'))
+		writeDone <- writeErr
+	}()
+
+	var writeErr error
+	select {
+	case writeErr = <-writeDone:
+	case <-time.After(time.Second):
+		t.Fatal("timed out writing oversized request")
+	}
+	if writeErr == nil {
+		_ = clientConn.SetReadDeadline(time.Now().Add(time.Second))
+		line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+		if err == nil || len(line) > 0 {
+			t.Fatalf("expected oversized request to close the connection, got line=%q err=%v", string(line), err)
+		}
+		return
+	}
+
+	if !strings.Contains(writeErr.Error(), "closed pipe") {
+		t.Fatalf("expected oversized request to close the connection, got write error %v", writeErr)
+	}
+}

miner_wire_test.go

@@ -0,0 +1,43 @@
+package proxy
+
+import (
+	"bufio"
+	"encoding/json"
+	"net"
+	"testing"
+)
+
+func TestMiner_Success_WritesNullError_Good(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := NewMiner(minerConn, 3333, nil)
+	done := make(chan struct{})
+	go func() {
+		miner.Success(7, "OK")
+		close(done)
+	}()
+
+	line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read success response: %v", err)
+	}
+	<-done
+
+	var payload struct {
+		Error  json.RawMessage `json:"error"`
+		Result struct {
+			Status string `json:"status"`
+		} `json:"result"`
+	}
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal success response: %v", err)
+	}
+	if string(payload.Error) != "null" {
+		t.Fatalf("expected success response error to be null, got %s", string(payload.Error))
+	}
+	if payload.Result.Status != "OK" {
+		t.Fatalf("expected success status OK, got %q", payload.Result.Status)
+	}
+}

miners_document_test.go

@@ -0,0 +1,87 @@
+package proxy
+
+import "testing"
+
+func TestProxy_MinersDocument_Good(t *testing.T) {
+	p := &Proxy{
+		miners: map[int64]*Miner{
+			1: {
+				id:       1,
+				ip:       "10.0.0.1:49152",
+				tx:       4096,
+				rx:       512,
+				state:    MinerStateReady,
+				diff:     100000,
+				user:     "WALLET",
+				password: "secret",
+				rigID:    "rig-alpha",
+				agent:    "XMRig/6.21.0",
+			},
+		},
+	}
+
+	document := p.MinersDocument()
+	if len(document.Miners) != 1 {
+		t.Fatalf("expected one miner row, got %d", len(document.Miners))
+	}
+	row := document.Miners[0]
+	if len(row) != 10 {
+		t.Fatalf("expected 10 miner columns, got %d", len(row))
+	}
+	if row[7] != "********" {
+		t.Fatalf("expected masked password, got %#v", row[7])
+	}
+}
+
+func TestProxy_MinersDocument_Bad(t *testing.T) {
+	var p *Proxy
+
+	document := p.MinersDocument()
+	if len(document.Miners) != 0 {
+		t.Fatalf("expected no miners for a nil proxy, got %d", len(document.Miners))
+	}
+	if len(document.Format) != 10 {
+		t.Fatalf("expected miner format columns to remain stable, got %d", len(document.Format))
+	}
+}
+
+func TestProxy_MinersDocument_Ugly(t *testing.T) {
+	p := &Proxy{
+		miners: map[int64]*Miner{
+			1: {
+				id:       1,
+				ip:       "10.0.0.1:49152",
+				tx:       4096,
+				rx:       512,
+				state:    MinerStateReady,
+				diff:     100000,
+				user:     "WALLET",
+				password: "secret-a",
+				rigID:    "rig-alpha",
+				agent:    "XMRig/6.21.0",
+			},
+			2: {
+				id:       2,
+				ip:       "10.0.0.2:49152",
+				tx:       2048,
+				rx:       256,
+				state:    MinerStateWaitReady,
+				diff:     50000,
+				user:     "WALLET2",
+				password: "secret-b",
+				rigID:    "rig-beta",
+				agent:    "XMRig/6.22.0",
+			},
+		},
+	}
+
+	document := p.MinersDocument()
+	if len(document.Miners) != 2 {
+		t.Fatalf("expected two miner rows, got %d", len(document.Miners))
+	}
+	for i, row := range document.Miners {
+		if row[7] != "********" {
+			t.Fatalf("expected masked password in row %d, got %#v", i, row[7])
+		}
+	}
+}

pool/client.go

@@ -1,7 +1,9 @@
-// Package pool implements the outbound stratum pool client and failover strategy.
+// Package pool implements the outbound pool client and failover strategy.
 //
-//	client := pool.NewStratumClient(poolCfg, listener)
-//	client.Connect()
+//	client := pool.NewStratumClient(proxy.PoolConfig{URL: "pool.example:3333", User: "WALLET", Pass: "x"}, listener)
+//	if result := client.Connect(); result.OK {
+//	    client.Login()
+//	}
 package pool
 
 import (
@@ -12,14 +14,13 @@ import (
 	"dappco.re/go/proxy"
 )
 
-// StratumClient is one outbound stratum TCP (optionally TLS) connection to a pool.
-// The proxy presents itself to the pool as a standard stratum miner using the
-// wallet address and password from PoolConfig.
+// client := pool.NewStratumClient(poolCfg, listener)
 //
-//	client := pool.NewStratumClient(poolCfg, listener)
-//	client.Connect()
+//	if result := client.Connect(); result.OK {
+//	    client.Login()
+//	}
 type StratumClient struct {
-	cfg        proxy.PoolConfig
+	config     proxy.PoolConfig
 	listener   StratumListener
 	conn       net.Conn
 	tlsConn    *tls.Conn // nil if plain TCP
@@ -32,7 +33,9 @@ type StratumClient struct {
 	sendMu     sync.Mutex
 }
 
-// StratumListener receives events from the pool connection.
+// type listener struct{}
+//
+// func (listener) OnJob(job proxy.Job) {}
 type StratumListener interface {
 	// OnJob is called when the pool pushes a new job notification or the login reply contains a job.
 	OnJob(job proxy.Job)

pool/impl.go

@@ -6,7 +6,6 @@ import (
 	"crypto/tls"
 	"encoding/hex"
 	"encoding/json"
-	"errors"
 	"io"
 	"net"
 	"strconv"
@@ -18,16 +17,27 @@ import (
 )
 
 // NewStrategyFactory creates a StrategyFactory for the supplied config.
-func NewStrategyFactory(cfg *proxy.Config) StrategyFactory {
+//
+//	factory := pool.NewStrategyFactory(&proxy.Config{Pools: []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}}})
+//	strategy := factory(listener)
+func NewStrategyFactory(config *proxy.Config) StrategyFactory {
 	return func(listener StratumListener) Strategy {
-		return NewFailoverStrategy(cfg.Pools, listener, cfg)
+		var pools []proxy.PoolConfig
+		if config != nil {
+			pools = config.Pools
+		}
+		return NewFailoverStrategy(pools, listener, config)
 	}
 }
 
-// NewStratumClient constructs a pool client.
-func NewStratumClient(cfg proxy.PoolConfig, listener StratumListener) *StratumClient {
+// client := pool.NewStratumClient(proxy.PoolConfig{URL: "pool.example:3333", User: "WALLET", Pass: "x"}, listener)
+//
+//	if result := client.Connect(); result.OK {
+//	    client.Login()
+//	}
+func NewStratumClient(poolConfig proxy.PoolConfig, listener StratumListener) *StratumClient {
 	return &StratumClient{
-		cfg:      cfg,
+		config:   poolConfig,
 		listener: listener,
 		pending:  make(map[int64]struct{}),
 	}
@@ -43,20 +53,20 @@ func (c *StratumClient) IsActive() bool {
 	return c.active
 }
 
-// Connect dials the pool.
+// result := client.Connect()
 func (c *StratumClient) Connect() proxy.Result {
 	if c == nil {
-		return proxy.Result{OK: false, Error: errors.New("client is nil")}
+		return proxy.Result{OK: false, Error: proxy.NewScopedError("proxy.pool.client", "client is nil", nil)}
 	}
-	addr := c.cfg.URL
+	addr := c.config.URL
 	if addr == "" {
-		return proxy.Result{OK: false, Error: errors.New("pool url is empty")}
+		return proxy.Result{OK: false, Error: proxy.NewScopedError("proxy.pool.client", "pool url is empty", nil)}
 	}
 	conn, err := net.Dial("tcp", addr)
 	if err != nil {
-		return proxy.Result{OK: false, Error: err}
+		return proxy.Result{OK: false, Error: proxy.NewScopedError("proxy.pool.client", "dial pool failed", err)}
 	}
-	if c.cfg.TLS {
+	if c.config.TLS {
 		host := addr
 		if strings.Contains(addr, ":") {
 			host, _, _ = net.SplitHostPort(addr)
@@ -65,18 +75,18 @@ func (c *StratumClient) Connect() proxy.Result {
 		tlsConn := tls.Client(conn, tlsCfg)
 		if err := tlsConn.Handshake(); err != nil {
 			_ = conn.Close()
-			return proxy.Result{OK: false, Error: err}
+			return proxy.Result{OK: false, Error: proxy.NewScopedError("proxy.pool.tls", "handshake failed", err)}
 		}
-		if fp := strings.TrimSpace(strings.ToLower(c.cfg.TLSFingerprint)); fp != "" {
+		if fp := strings.TrimSpace(strings.ToLower(c.config.TLSFingerprint)); fp != "" {
 			cert := tlsConn.ConnectionState().PeerCertificates
 			if len(cert) == 0 {
 				_ = tlsConn.Close()
-				return proxy.Result{OK: false, Error: errors.New("missing certificate")}
+				return proxy.Result{OK: false, Error: proxy.NewScopedError("proxy.pool.tls", "missing certificate", nil)}
 			}
 			sum := sha256.Sum256(cert[0].Raw)
 			if hex.EncodeToString(sum[:]) != fp {
 				_ = tlsConn.Close()
-				return proxy.Result{OK: false, Error: errors.New("tls fingerprint mismatch")}
+				return proxy.Result{OK: false, Error: proxy.NewScopedError("proxy.pool.tls", "tls fingerprint mismatch", nil)}
 			}
 		}
 		c.conn = tlsConn
@@ -88,20 +98,22 @@ func (c *StratumClient) Connect() proxy.Result {
 	return proxy.Result{OK: true}
 }
 
-// Login sends the miner-style login request to the pool.
+// client.Login()
+//
+// A login reply with a job triggers `OnJob` immediately.
 func (c *StratumClient) Login() {
 	if c == nil || c.conn == nil {
 		return
 	}
 	params := map[string]any{
-		"login": c.cfg.User,
-		"pass":  c.cfg.Pass,
+		"login": c.config.User,
+		"pass":  c.config.Pass,
 	}
-	if c.cfg.RigID != "" {
-		params["rigid"] = c.cfg.RigID
+	if c.config.RigID != "" {
+		params["rigid"] = c.config.RigID
 	}
-	if c.cfg.Algo != "" {
-		params["algo"] = []string{c.cfg.Algo}
+	if c.config.Algo != "" {
+		params["algo"] = []string{c.config.Algo}
 	}
 	req := map[string]any{
 		"id":      1,
@@ -112,7 +124,7 @@ func (c *StratumClient) Login() {
 	_ = c.writeJSON(req)
 }
 
-// Submit forwards a share to the pool.
+// seq := client.Submit("job-1", "deadbeef", "HASH64HEX", "cn/r")
 func (c *StratumClient) Submit(jobID, nonce, result, algo string) int64 {
 	if c == nil {
 		return 0
@@ -134,18 +146,39 @@ func (c *StratumClient) Submit(jobID, nonce, result, algo string) int64 {
 			"algo":   algo,
 		},
 	}
-	_ = c.writeJSON(req)
+	if err := c.writeJSON(req); err != nil {
+		c.mu.Lock()
+		delete(c.pending, seq)
+		c.mu.Unlock()
+	}
 	return seq
 }
 
-// Disconnect closes the connection and notifies the listener.
+// client.Keepalive()
+func (c *StratumClient) Keepalive() {
+	if c == nil || c.conn == nil || !c.IsActive() {
+		return
+	}
+	req := map[string]any{
+		"id":      atomic.AddInt64(&c.seq, 1),
+		"jsonrpc": "2.0",
+		"method":  "keepalived",
+		"params": map[string]any{
+			"id": c.sessionID,
+		},
+	}
+	_ = c.writeJSON(req)
+}
+
+// client.Disconnect()
 func (c *StratumClient) Disconnect() {
 	if c == nil {
 		return
 	}
 	c.closedOnce.Do(func() {
-		if c.conn != nil {
-			_ = c.conn.Close()
+		conn := c.resetConnectionState()
+		if conn != nil {
+			_ = conn.Close()
 		}
 		if c.listener != nil {
 			c.listener.OnDisconnect()
@@ -155,26 +188,43 @@ func (c *StratumClient) Disconnect() {
 
 func (c *StratumClient) notifyDisconnect() {
 	c.closedOnce.Do(func() {
+		c.resetConnectionState()
 		if c.listener != nil {
 			c.listener.OnDisconnect()
 		}
 	})
 }
 
+func (c *StratumClient) resetConnectionState() net.Conn {
+	if c == nil {
+		return nil
+	}
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	conn := c.conn
+	c.conn = nil
+	c.tlsConn = nil
+	c.sessionID = ""
+	c.active = false
+	c.pending = make(map[int64]struct{})
+	return conn
+}
+
 func (c *StratumClient) writeJSON(payload any) error {
 	c.sendMu.Lock()
 	defer c.sendMu.Unlock()
 	if c.conn == nil {
-		return errors.New("connection is nil")
+		return proxy.NewScopedError("proxy.pool.client", "connection is nil", nil)
 	}
 	data, err := json.Marshal(payload)
 	if err != nil {
-		return err
+		return proxy.NewScopedError("proxy.pool.client", "marshal request failed", err)
 	}
 	data = append(data, '\n')
 	_, err = c.conn.Write(data)
 	if err != nil {
 		c.notifyDisconnect()
+		return proxy.NewScopedError("proxy.pool.client", "write request failed", err)
 	}
 	return err
 }
@@ -251,6 +301,11 @@ func (c *StratumClient) handleMessage(line []byte) {
 		}
 	}
 
+	if len(base.Error) > 0 && requestID(base.ID) == 1 {
+		c.notifyDisconnect()
+		return
+	}
+
 	if base.Method == "job" {
 		var params struct {
 			Blob     string `json:"blob"`
@@ -319,37 +374,38 @@ func (c *StratumClient) handleMessage(line []byte) {
 }
 
 // NewFailoverStrategy creates the ordered pool failover wrapper.
-func NewFailoverStrategy(pools []proxy.PoolConfig, listener StratumListener, cfg *proxy.Config) *FailoverStrategy {
+func NewFailoverStrategy(pools []proxy.PoolConfig, listener StratumListener, config *proxy.Config) *FailoverStrategy {
 	return &FailoverStrategy{
 		pools:    pools,
 		listener: listener,
-		cfg:      cfg,
+		config:   config,
 	}
 }
 
-// Connect establishes the first reachable pool connection.
+// strategy.Connect()
 func (s *FailoverStrategy) Connect() {
 	if s == nil {
 		return
 	}
 	s.mu.Lock()
 	defer s.mu.Unlock()
+	s.closing = false
 	s.connectLocked(0)
 }
 
 func (s *FailoverStrategy) connectLocked(start int) {
-	enabled := enabledPools(s.pools)
+	enabled := enabledPools(s.currentPools())
 	if len(enabled) == 0 {
 		return
 	}
 	retries := 1
 	retryPause := time.Second
-	if s.cfg != nil {
-		if s.cfg.Retries > 0 {
-			retries = s.cfg.Retries
+	if s.config != nil {
+		if s.config.Retries > 0 {
+			retries = s.config.Retries
 		}
-		if s.cfg.RetryPause > 0 {
-			retryPause = time.Duration(s.cfg.RetryPause) * time.Second
+		if s.config.RetryPause > 0 {
+			retryPause = time.Duration(s.config.RetryPause) * time.Second
 		}
 	}
 	for attempt := 0; attempt < retries; attempt++ {
@@ -368,7 +424,17 @@ func (s *FailoverStrategy) connectLocked(start int) {
 	}
 }
 
-// Submit sends the share through the active client.
+func (s *FailoverStrategy) currentPools() []proxy.PoolConfig {
+	if s == nil {
+		return nil
+	}
+	if s.config != nil && len(s.config.Pools) > 0 {
+		return s.config.Pools
+	}
+	return s.pools
+}
+
+// seq := strategy.Submit(jobID, nonce, result, algo)
 func (s *FailoverStrategy) Submit(jobID, nonce, result, algo string) int64 {
 	if s == nil || s.client == nil {
 		return 0
@@ -376,24 +442,51 @@ func (s *FailoverStrategy) Submit(jobID, nonce, result, algo string) int64 {
 	return s.client.Submit(jobID, nonce, result, algo)
 }
 
-// Disconnect closes the active client.
+// strategy.Disconnect()
 func (s *FailoverStrategy) Disconnect() {
 	if s == nil {
 		return
 	}
 	s.mu.Lock()
-	defer s.mu.Unlock()
-	if s.client != nil {
-		s.client.Disconnect()
-		s.client = nil
+	client := s.client
+	s.closing = true
+	s.client = nil
+	s.mu.Unlock()
+	if client != nil {
+		client.Disconnect()
 	}
 }
 
-// IsActive reports whether the current client has received a job.
+// strategy.ReloadPools()
+func (s *FailoverStrategy) ReloadPools() {
+	if s == nil {
+		return
+	}
+	s.mu.Lock()
+	s.current = 0
+	s.mu.Unlock()
+	s.Disconnect()
+	s.Connect()
+}
+
+// active := strategy.IsActive()
 func (s *FailoverStrategy) IsActive() bool {
 	return s != nil && s.client != nil && s.client.IsActive()
 }
 
+// Tick keeps an active pool connection alive when configured.
+func (s *FailoverStrategy) Tick(ticks uint64) {
+	if s == nil || ticks == 0 || ticks%60 != 0 {
+		return
+	}
+	s.mu.Lock()
+	client := s.client
+	s.mu.Unlock()
+	if client != nil && client.config.Keepalive {
+		client.Keepalive()
+	}
+}
+
 // OnJob forwards the pool job to the outer listener.
 func (s *FailoverStrategy) OnJob(job proxy.Job) {
 	if s != nil && s.listener != nil {
@@ -408,11 +501,21 @@ func (s *FailoverStrategy) OnResultAccepted(sequence int64, accepted bool, error
 	}
 }
 
-// OnDisconnect retries from the primary pool and forwards the disconnect.
+// strategy.OnDisconnect()
 func (s *FailoverStrategy) OnDisconnect() {
 	if s == nil {
 		return
 	}
+	s.mu.Lock()
+	s.client = nil
+	closing := s.closing
+	if closing {
+		s.closing = false
+	}
+	s.mu.Unlock()
+	if closing {
+		return
+	}
 	if s.listener != nil {
 		s.listener.OnDisconnect()
 	}

pool/impl_test.go

@@ -0,0 +1,168 @@
+package pool
+
+import (
+	"testing"
+
+	"dappco.re/go/proxy"
+)
+
+// TestFailoverStrategy_CurrentPools_Good verifies that currentPools follows the live config.
+//
+//	strategy := pool.NewFailoverStrategy(cfg.Pools, nil, cfg)
+//	strategy.currentPools() // returns cfg.Pools
+func TestFailoverStrategy_CurrentPools_Good(t *testing.T) {
+	cfg := &proxy.Config{
+		Mode:    "nicehash",
+		Workers: proxy.WorkersByRigID,
+		Bind:    []proxy.BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []proxy.PoolConfig{{URL: "pool-a.example:3333", Enabled: true}},
+	}
+	strategy := NewFailoverStrategy(cfg.Pools, nil, cfg)
+
+	if got := len(strategy.currentPools()); got != 1 {
+		t.Fatalf("expected 1 pool, got %d", got)
+	}
+
+	cfg.Pools = []proxy.PoolConfig{{URL: "pool-b.example:4444", Enabled: true}}
+
+	if got := strategy.currentPools(); len(got) != 1 || got[0].URL != "pool-b.example:4444" {
+		t.Fatalf("expected current pools to follow config reload, got %+v", got)
+	}
+}
+
+// TestFailoverStrategy_CurrentPools_Bad verifies that a nil strategy returns an empty pool list.
+//
+//	var strategy *pool.FailoverStrategy
+//	strategy.currentPools() // nil
+func TestFailoverStrategy_CurrentPools_Bad(t *testing.T) {
+	var strategy *FailoverStrategy
+	pools := strategy.currentPools()
+	if pools != nil {
+		t.Fatalf("expected nil pools from nil strategy, got %+v", pools)
+	}
+}
+
+// TestFailoverStrategy_CurrentPools_Ugly verifies that a strategy with a nil config
+// falls back to the pools passed at construction time.
+//
+//	strategy := pool.NewFailoverStrategy(initialPools, nil, nil)
+//	strategy.currentPools() // returns initialPools
+func TestFailoverStrategy_CurrentPools_Ugly(t *testing.T) {
+	initialPools := []proxy.PoolConfig{
+		{URL: "fallback.example:3333", Enabled: true},
+		{URL: "fallback.example:4444", Enabled: false},
+	}
+	strategy := NewFailoverStrategy(initialPools, nil, nil)
+
+	got := strategy.currentPools()
+	if len(got) != 2 {
+		t.Fatalf("expected 2 pools from constructor fallback, got %d", len(got))
+	}
+	if got[0].URL != "fallback.example:3333" {
+		t.Fatalf("expected constructor pool URL, got %q", got[0].URL)
+	}
+}
+
+// TestFailoverStrategy_EnabledPools_Good verifies that only enabled pools are selected.
+//
+//	enabled := pool.enabledPools(pools) // filters to enabled-only
+func TestFailoverStrategy_EnabledPools_Good(t *testing.T) {
+	pools := []proxy.PoolConfig{
+		{URL: "active.example:3333", Enabled: true},
+		{URL: "disabled.example:3333", Enabled: false},
+		{URL: "active2.example:3333", Enabled: true},
+	}
+	got := enabledPools(pools)
+	if len(got) != 2 {
+		t.Fatalf("expected 2 enabled pools, got %d", len(got))
+	}
+	if got[0].URL != "active.example:3333" || got[1].URL != "active2.example:3333" {
+		t.Fatalf("expected only enabled pool URLs, got %+v", got)
+	}
+}
+
+// TestFailoverStrategy_EnabledPools_Bad verifies that an empty pool list returns empty.
+//
+//	pool.enabledPools(nil) // empty
+func TestFailoverStrategy_EnabledPools_Bad(t *testing.T) {
+	got := enabledPools(nil)
+	if len(got) != 0 {
+		t.Fatalf("expected 0 pools from nil input, got %d", len(got))
+	}
+}
+
+// TestFailoverStrategy_EnabledPools_Ugly verifies that all-disabled pools return empty.
+//
+//	pool.enabledPools([]proxy.PoolConfig{{Enabled: false}}) // empty
+func TestFailoverStrategy_EnabledPools_Ugly(t *testing.T) {
+	pools := []proxy.PoolConfig{
+		{URL: "a.example:3333", Enabled: false},
+		{URL: "b.example:3333", Enabled: false},
+	}
+	got := enabledPools(pools)
+	if len(got) != 0 {
+		t.Fatalf("expected 0 enabled pools when all disabled, got %d", len(got))
+	}
+}
+
+// TestNewStrategyFactory_Good verifies the factory creates a strategy connected to the config.
+//
+//	factory := pool.NewStrategyFactory(cfg)
+//	strategy := factory(listener) // creates FailoverStrategy
+func TestNewStrategyFactory_Good(t *testing.T) {
+	cfg := &proxy.Config{
+		Mode:    "nicehash",
+		Workers: proxy.WorkersByRigID,
+		Bind:    []proxy.BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	factory := NewStrategyFactory(cfg)
+	if factory == nil {
+		t.Fatal("expected a non-nil factory")
+	}
+	strategy := factory(nil)
+	if strategy == nil {
+		t.Fatal("expected a non-nil strategy from factory")
+	}
+	if strategy.IsActive() {
+		t.Fatal("expected new strategy to be inactive before connecting")
+	}
+}
+
+// TestNewStrategyFactory_Bad verifies a factory created with nil config does not panic.
+//
+//	factory := pool.NewStrategyFactory(nil)
+//	strategy := factory(nil)
+func TestNewStrategyFactory_Bad(t *testing.T) {
+	factory := NewStrategyFactory(nil)
+	strategy := factory(nil)
+	if strategy == nil {
+		t.Fatal("expected a non-nil strategy even from nil config")
+	}
+}
+
+// TestNewStrategyFactory_Ugly verifies the factory forwards the correct pool list to the strategy.
+//
+//	cfg.Pools = append(cfg.Pools, proxy.PoolConfig{URL: "added.example:3333", Enabled: true})
+//	strategy := factory(nil)
+//	// strategy sees the updated pools via the shared config pointer
+func TestNewStrategyFactory_Ugly(t *testing.T) {
+	cfg := &proxy.Config{
+		Mode:    "nicehash",
+		Workers: proxy.WorkersByRigID,
+		Bind:    []proxy.BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	factory := NewStrategyFactory(cfg)
+	cfg.Pools = append(cfg.Pools, proxy.PoolConfig{URL: "added.example:3333", Enabled: true})
+
+	strategy := factory(nil)
+	fs, ok := strategy.(*FailoverStrategy)
+	if !ok {
+		t.Fatal("expected FailoverStrategy")
+	}
+	pools := fs.currentPools()
+	if len(pools) != 2 {
+		t.Fatalf("expected 2 pools after config update, got %d", len(pools))
+	}
+}

pool/keepalive_test.go

@@ -0,0 +1,112 @@
+package pool
+
+import (
+	"bufio"
+	"encoding/json"
+	"net"
+	"testing"
+	"time"
+)
+
+func TestStratumClient_Keepalive_Good(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+	defer clientConn.Close()
+
+	client := &StratumClient{
+		conn:      clientConn,
+		active:    true,
+		sessionID: "session-1",
+	}
+
+	done := make(chan struct{})
+	go func() {
+		client.Keepalive()
+		close(done)
+	}()
+
+	line, err := bufio.NewReader(serverConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read keepalive request: %v", err)
+	}
+	<-done
+
+	var payload map[string]any
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal keepalive request: %v", err)
+	}
+	if got := payload["method"]; got != "keepalived" {
+		t.Fatalf("expected keepalived method, got %#v", got)
+	}
+	params, ok := payload["params"].(map[string]any)
+	if !ok {
+		t.Fatalf("expected params object, got %#v", payload["params"])
+	}
+	if got := params["id"]; got != "session-1" {
+		t.Fatalf("expected session id in keepalive payload, got %#v", got)
+	}
+}
+
+func TestStratumClient_Keepalive_Bad(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+	defer clientConn.Close()
+
+	client := &StratumClient{
+		conn:   clientConn,
+		active: false,
+	}
+
+	client.Keepalive()
+
+	if err := serverConn.SetReadDeadline(time.Now().Add(50 * time.Millisecond)); err != nil {
+		t.Fatalf("set deadline: %v", err)
+	}
+	buf := make([]byte, 1)
+	if _, err := serverConn.Read(buf); err == nil {
+		t.Fatalf("expected no keepalive data while inactive")
+	}
+}
+
+func TestStratumClient_Keepalive_Ugly(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+	defer clientConn.Close()
+
+	client := &StratumClient{
+		conn:      clientConn,
+		active:    true,
+		sessionID: "session-2",
+	}
+
+	reader := bufio.NewReader(serverConn)
+	done := make(chan struct{})
+	go func() {
+		client.Keepalive()
+		client.Keepalive()
+		close(done)
+	}()
+
+	first, err := reader.ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read first keepalive request: %v", err)
+	}
+	second, err := reader.ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read second keepalive request: %v", err)
+	}
+	<-done
+
+	var firstPayload map[string]any
+	if err := json.Unmarshal(first, &firstPayload); err != nil {
+		t.Fatalf("unmarshal first keepalive request: %v", err)
+	}
+	var secondPayload map[string]any
+	if err := json.Unmarshal(second, &secondPayload); err != nil {
+		t.Fatalf("unmarshal second keepalive request: %v", err)
+	}
+
+	if firstPayload["id"] == secondPayload["id"] {
+		t.Fatalf("expected keepalive request ids to be unique")
+	}
+}

pool/strategy.go

@@ -7,31 +7,39 @@ import (
 )
 
 // FailoverStrategy wraps an ordered slice of PoolConfig entries.
-// It connects to the first enabled pool and fails over in order on error.
-// On reconnect it always retries from the primary first.
 //
-//	strategy := pool.NewFailoverStrategy(cfg.Pools, listener, cfg)
+//	strategy := pool.NewFailoverStrategy([]proxy.PoolConfig{
+//	    {URL: "primary.example:3333", Enabled: true},
+//	    {URL: "backup.example:3333", Enabled: true},
+//	}, listener, cfg)
 //	strategy.Connect()
 type FailoverStrategy struct {
 	pools    []proxy.PoolConfig
 	current  int
 	client   *StratumClient
 	listener StratumListener
-	cfg      *proxy.Config
+	config   *proxy.Config
+	closing  bool
 	mu       sync.Mutex
 }
 
-// StrategyFactory creates a new FailoverStrategy for a given StratumListener.
-// Used by splitters to create per-mapper strategies without coupling to Config.
+// StrategyFactory creates a FailoverStrategy for a given StratumListener.
 //
 //	factory := pool.NewStrategyFactory(cfg)
-//	strategy := factory(listener)   // each mapper calls this
+//	strategy := factory(listener)
 type StrategyFactory func(listener StratumListener) Strategy
 
-// Strategy is the interface the splitters use to submit shares and check pool state.
+// Strategy is the interface splitters use to submit shares and inspect pool state.
 type Strategy interface {
 	Connect()
 	Submit(jobID, nonce, result, algo string) int64
 	Disconnect()
 	IsActive() bool
 }
+
+// ReloadableStrategy re-establishes an upstream connection after config changes.
+//
+//	strategy.ReloadPools()
+type ReloadableStrategy interface {
+	ReloadPools()
+}

pool/strategy_disconnect_test.go

@@ -0,0 +1,148 @@
+package pool
+
+import (
+	"encoding/json"
+	"net"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"dappco.re/go/proxy"
+)
+
+type disconnectSpy struct {
+	disconnects atomic.Int64
+}
+
+func (s *disconnectSpy) OnJob(proxy.Job) {}
+
+func (s *disconnectSpy) OnResultAccepted(int64, bool, string) {}
+
+func (s *disconnectSpy) OnDisconnect() {
+	s.disconnects.Add(1)
+}
+
+func TestFailoverStrategy_Disconnect_Good(t *testing.T) {
+	spy := &disconnectSpy{}
+	strategy := &FailoverStrategy{
+		listener: spy,
+		client:   &StratumClient{listener: nil},
+	}
+	strategy.client.listener = strategy
+
+	strategy.Disconnect()
+	time.Sleep(10 * time.Millisecond)
+
+	if got := spy.disconnects.Load(); got != 0 {
+		t.Fatalf("expected intentional disconnect to suppress reconnect, got %d listener calls", got)
+	}
+}
+
+func TestFailoverStrategy_Disconnect_Bad(t *testing.T) {
+	spy := &disconnectSpy{}
+	strategy := &FailoverStrategy{listener: spy}
+
+	strategy.OnDisconnect()
+
+	if got := spy.disconnects.Load(); got != 1 {
+		t.Fatalf("expected external disconnect to notify listener once, got %d", got)
+	}
+}
+
+func TestFailoverStrategy_Disconnect_Ugly(t *testing.T) {
+	spy := &disconnectSpy{}
+	strategy := &FailoverStrategy{
+		listener: spy,
+		client:   &StratumClient{listener: nil},
+	}
+	strategy.client.listener = strategy
+
+	strategy.Disconnect()
+	strategy.Disconnect()
+	time.Sleep(10 * time.Millisecond)
+
+	if got := spy.disconnects.Load(); got != 0 {
+		t.Fatalf("expected repeated intentional disconnects to remain silent, got %d listener calls", got)
+	}
+}
+
+func TestStratumClient_NotifyDisconnect_ClearsState_Good(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+
+	spy := &disconnectSpy{}
+	client := &StratumClient{
+		conn:      clientConn,
+		listener:  spy,
+		sessionID: "session-1",
+		active:    true,
+		pending: map[int64]struct{}{
+			7: {},
+		},
+	}
+
+	client.notifyDisconnect()
+
+	if got := spy.disconnects.Load(); got != 1 {
+		t.Fatalf("expected one disconnect notification, got %d", got)
+	}
+	if client.conn != nil {
+		t.Fatalf("expected pooled connection to be cleared")
+	}
+	if client.sessionID != "" {
+		t.Fatalf("expected session id to be cleared, got %q", client.sessionID)
+	}
+	if client.IsActive() {
+		t.Fatalf("expected client to stop reporting active after disconnect")
+	}
+	if len(client.pending) != 0 {
+		t.Fatalf("expected pending submit state to be cleared, got %d entries", len(client.pending))
+	}
+}
+
+func TestFailoverStrategy_OnDisconnect_ClearsClient_Bad(t *testing.T) {
+	spy := &disconnectSpy{}
+	strategy := &FailoverStrategy{
+		listener: spy,
+		client:   &StratumClient{active: true, pending: make(map[int64]struct{})},
+	}
+
+	strategy.OnDisconnect()
+	time.Sleep(10 * time.Millisecond)
+
+	if strategy.client != nil {
+		t.Fatalf("expected strategy to drop the stale client before reconnect")
+	}
+	if strategy.IsActive() {
+		t.Fatalf("expected strategy to report inactive while reconnect is pending")
+	}
+	if got := spy.disconnects.Load(); got != 1 {
+		t.Fatalf("expected one disconnect notification, got %d", got)
+	}
+}
+
+func TestStratumClient_HandleMessage_LoginErrorDisconnects_Ugly(t *testing.T) {
+	spy := &disconnectSpy{}
+	client := &StratumClient{
+		listener: spy,
+		pending:  make(map[int64]struct{}),
+	}
+
+	payload, err := json.Marshal(map[string]any{
+		"id":      1,
+		"jsonrpc": "2.0",
+		"error": map[string]any{
+			"code":    -1,
+			"message": "Invalid payment address provided",
+		},
+	})
+	if err != nil {
+		t.Fatalf("marshal login error payload: %v", err)
+	}
+
+	client.handleMessage(payload)
+
+	if got := spy.disconnects.Load(); got != 1 {
+		t.Fatalf("expected login failure to disconnect upstream once, got %d", got)
+	}
+}

proxy.go

@@ -1,45 +1,59 @@
-// Package proxy is a CryptoNote stratum mining proxy library.
-//
-// It accepts miner connections over TCP (optionally TLS), splits the 32-bit nonce
-// space across up to 256 simultaneous miners per upstream pool connection (NiceHash
-// mode), and presents a small monitoring API.
-//
-// Full specification: docs/RFC.md
+// Package proxy is the mining proxy library.
 //
+//	cfg := &proxy.Config{Mode: "nicehash", Bind: []proxy.BindAddr{{Host: "0.0.0.0", Port: 3333}}, Pools: []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}}, Workers: proxy.WorkersByRigID}
 //	p, result := proxy.New(cfg)
-//	if result.OK { p.Start() }
+//	if result.OK {
+//	    p.Start()
+//	}
 package proxy
 
 import (
 	"net/http"
 	"sync"
+	"sync/atomic"
 	"time"
 )
 
-// Proxy is the top-level orchestrator. It owns the server, splitter, stats, workers,
-// event bus, tick goroutine, and optional HTTP API.
+// Proxy wires the configured listeners, splitters, stats, workers, and log sinks.
 //
+//	cfg := &proxy.Config{
+//	    Mode:    "nicehash",
+//	    Bind:    []proxy.BindAddr{{Host: "0.0.0.0", Port: 3333}},
+//	    Pools:   []proxy.PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+//	    Workers: proxy.WorkersByRigID,
+//	}
 //	p, result := proxy.New(cfg)
-//	if result.OK { p.Start() }
+//	if result.OK {
+//	    p.Start()
+//	}
 type Proxy struct {
-	config     *Config
-	splitter   Splitter
-	stats      *Stats
-	workers    *Workers
-	events     *EventBus
-	servers    []*Server
-	ticker     *time.Ticker
-	watcher    *ConfigWatcher
-	done       chan struct{}
-	stopOnce   sync.Once
-	minersMu   sync.RWMutex
-	miners     map[int64]*Miner
-	customDiff *CustomDiff
-	rateLimit  *RateLimiter
-	httpServer *http.Server
+	config            *Config
+	configMu          sync.RWMutex
+	splitter          Splitter
+	shareSink         ShareSink
+	stats             *Stats
+	workers           *Workers
+	events            *EventBus
+	servers           []*Server
+	ticker            *time.Ticker
+	watcher           *ConfigWatcher
+	done              chan struct{}
+	stopOnce          sync.Once
+	minersMu          sync.RWMutex
+	miners            map[int64]*Miner
+	customDiff        *CustomDiff
+	customDiffBuckets *CustomDiffBuckets
+	rateLimit         *RateLimiter
+	httpServer        *http.Server
+	accessLog         *accessLogSink
+	shareLog          *shareLogSink
+	submitCount       atomic.Int64
 }
 
-// Splitter is the interface both NonceSplitter and SimpleSplitter satisfy.
+// Splitter routes miner logins, submits, and disconnects to the active upstream strategy.
+//
+//	splitter := nicehash.NewNonceSplitter(cfg, bus, pool.NewStrategyFactory(cfg))
+//	splitter.Connect()
 type Splitter interface {
 	// Connect establishes the first pool upstream connection.
 	Connect()
@@ -57,7 +71,18 @@ type Splitter interface {
 	Upstreams() UpstreamStats
 }
 
-// UpstreamStats carries pool connection state counts for monitoring.
+// ShareSink consumes share outcomes from the proxy event stream.
+//
+//	sink.OnAccept(proxy.Event{Miner: miner, Diff: 100000})
+//	sink.OnReject(proxy.Event{Miner: miner, Error: "Invalid nonce"})
+type ShareSink interface {
+	OnAccept(Event)
+	OnReject(Event)
+}
+
+// UpstreamStats reports pool connection counts.
+//
+//	stats := proxy.UpstreamStats{Active: 1, Sleep: 0, Error: 0, Total: 1}
 type UpstreamStats struct {
 	Active uint64 // connections currently receiving jobs
 	Sleep  uint64 // idle connections (simple mode reuse pool)
@@ -65,12 +90,16 @@ type UpstreamStats struct {
 	Total  uint64 // Active + Sleep + Error
 }
 
-// LoginEvent is dispatched when a miner completes the login handshake.
+// LoginEvent is dispatched when a miner completes login.
+//
+//	event := proxy.LoginEvent{Miner: miner}
 type LoginEvent struct {
 	Miner *Miner
 }
 
-// SubmitEvent is dispatched when a miner submits a share.
+// SubmitEvent carries one miner share submission.
+//
+//	event := proxy.SubmitEvent{Miner: miner, JobID: "job-1", Nonce: "deadbeef", Result: "HASH", RequestID: 2}
 type SubmitEvent struct {
 	Miner     *Miner
 	JobID     string
@@ -80,50 +109,56 @@ type SubmitEvent struct {
 	RequestID int64
 }
 
-// CloseEvent is dispatched when a miner TCP connection closes.
+// CloseEvent is dispatched when a miner connection closes.
+//
+//	event := proxy.CloseEvent{Miner: miner}
 type CloseEvent struct {
 	Miner *Miner
 }
 
-// ConfigWatcher polls a config file for mtime changes and calls onChange on modification.
-// Uses 1-second polling; does not require fsnotify.
+// ConfigWatcher polls a config file every second and reloads on modification.
 //
-//	w := proxy.NewConfigWatcher("config.json", func(cfg *proxy.Config) {
+//	watcher := proxy.NewConfigWatcher("config.json", func(cfg *proxy.Config) {
 //	    p.Reload(cfg)
 //	})
-//	w.Start()
+//	watcher.Start()
 type ConfigWatcher struct {
-	path     string
-	onChange func(*Config)
-	lastMod  time.Time
-	done     chan struct{}
+	configPath     string
+	onConfigChange func(*Config)
+	lastModifiedAt time.Time
+	stopCh         chan struct{}
+	mu             sync.Mutex
+	started        bool
 }
 
-// RateLimiter implements per-IP token bucket connection rate limiting.
-// Each unique IP has a bucket initialised to MaxConnectionsPerMinute tokens.
-// Each connection attempt consumes one token. Tokens refill at 1 per (60/max) seconds.
-// An IP that empties its bucket is added to a ban list for BanDurationSeconds.
+// RateLimiter throttles new connections per source IP.
 //
-//	rl := proxy.NewRateLimiter(cfg.RateLimit)
-//	if !rl.Allow("1.2.3.4") { conn.Close(); return }
+//	limiter := proxy.NewRateLimiter(proxy.RateLimit{
+//	    MaxConnectionsPerMinute: 30,
+//	    BanDurationSeconds:      300,
+//	})
+//	if limiter.Allow("1.2.3.4:3333") {
+//	    // accept the socket
+//	}
 type RateLimiter struct {
-	cfg     RateLimit
-	buckets map[string]*tokenBucket
-	banned  map[string]time.Time
-	mu      sync.Mutex
+	limit          RateLimit
+	bucketByHost   map[string]*tokenBucket
+	banUntilByHost map[string]time.Time
+	mu             sync.Mutex
 }
 
-// tokenBucket is a simple token bucket for one IP.
+// tokenBucket is the per-IP refillable counter.
+//
+//	bucket := tokenBucket{tokens: 30, lastRefill: time.Now()}
 type tokenBucket struct {
 	tokens     int
 	lastRefill time.Time
 }
 
-// CustomDiff resolves and applies per-miner difficulty overrides at login time.
-// Resolution order: user-suffix (+N) > Config.CustomDiff > pool difficulty.
+// CustomDiff applies a login-time difficulty override.
 //
-//	cd := proxy.NewCustomDiff(cfg.CustomDiff)
-//	bus.Subscribe(proxy.EventLogin, cd.OnLogin)
+//	resolver := proxy.NewCustomDiff(50000)
+//	resolver.Apply(&Miner{user: "WALLET+75000"})
 type CustomDiff struct {
-	globalDiff uint64
+	globalDiff atomic.Uint64
 }

ratelimit_test.go

@@ -1,13 +1,115 @@
 package proxy
 
-import "testing"
+import (
+	"testing"
+	"time"
+)
 
-func TestRateLimiter_Allow(t *testing.T) {
-	rl := NewRateLimiter(RateLimit{MaxConnectionsPerMinute: 1, BanDurationSeconds: 1})
-	if !rl.Allow("1.2.3.4:1234") {
-		t.Fatalf("expected first call to pass")
-	}
-	if rl.Allow("1.2.3.4:1234") {
-		t.Fatalf("expected second call to fail")
+// TestRateLimiter_Allow_Good verifies the first N calls within budget are allowed.
+//
+//	limiter := proxy.NewRateLimiter(proxy.RateLimit{MaxConnectionsPerMinute: 10})
+//	limiter.Allow("1.2.3.4:3333") // true (first 10 calls)
+func TestRateLimiter_Allow_Good(t *testing.T) {
+	rl := NewRateLimiter(RateLimit{MaxConnectionsPerMinute: 10, BanDurationSeconds: 60})
+
+	for i := 0; i < 10; i++ {
+		if !rl.Allow("1.2.3.4:3333") {
+			t.Fatalf("expected call %d to be allowed", i+1)
+		}
+	}
+}
+
+// TestRateLimiter_Allow_Bad verifies the 11th call fails when budget is 10/min.
+//
+//	limiter := proxy.NewRateLimiter(proxy.RateLimit{MaxConnectionsPerMinute: 10})
+//	// calls 1-10 pass, call 11 fails
+func TestRateLimiter_Allow_Bad(t *testing.T) {
+	rl := NewRateLimiter(RateLimit{MaxConnectionsPerMinute: 10, BanDurationSeconds: 60})
+
+	for i := 0; i < 10; i++ {
+		rl.Allow("1.2.3.4:3333")
+	}
+	if rl.Allow("1.2.3.4:3333") {
+		t.Fatalf("expected 11th call to be rejected")
+	}
+}
+
+// TestRateLimiter_Allow_Ugly verifies a banned IP stays banned for BanDurationSeconds.
+//
+//	limiter := proxy.NewRateLimiter(proxy.RateLimit{MaxConnectionsPerMinute: 1, BanDurationSeconds: 300})
+//	limiter.Allow("1.2.3.4:3333") // true (exhausts budget)
+//	limiter.Allow("1.2.3.4:3333") // false (banned for 300 seconds)
+func TestRateLimiter_Allow_Ugly(t *testing.T) {
+	rl := NewRateLimiter(RateLimit{MaxConnectionsPerMinute: 1, BanDurationSeconds: 300})
+
+	if !rl.Allow("1.2.3.4:3333") {
+		t.Fatalf("expected first call to pass")
+	}
+	if rl.Allow("1.2.3.4:3333") {
+		t.Fatalf("expected second call to fail")
+	}
+
+	// Verify the IP is still banned even with a fresh bucket
+	rl.mu.Lock()
+	rl.bucketByHost["1.2.3.4"] = &tokenBucket{tokens: 100, lastRefill: time.Now()}
+	rl.mu.Unlock()
+	if rl.Allow("1.2.3.4:3333") {
+		t.Fatalf("expected banned IP to remain banned regardless of fresh bucket")
+	}
+}
+
+// TestRateLimiter_Tick_Good verifies Tick removes expired bans.
+//
+//	limiter := proxy.NewRateLimiter(proxy.RateLimit{MaxConnectionsPerMinute: 1, BanDurationSeconds: 1})
+//	limiter.Tick()
+func TestRateLimiter_Tick_Good(t *testing.T) {
+	rl := NewRateLimiter(RateLimit{MaxConnectionsPerMinute: 1, BanDurationSeconds: 1})
+
+	rl.Allow("1.2.3.4:3333")
+	rl.Allow("1.2.3.4:3333") // triggers ban
+
+	// Simulate expired ban
+	rl.mu.Lock()
+	rl.banUntilByHost["1.2.3.4"] = time.Now().Add(-time.Second)
+	rl.mu.Unlock()
+
+	rl.Tick()
+
+	rl.mu.Lock()
+	_, banned := rl.banUntilByHost["1.2.3.4"]
+	rl.mu.Unlock()
+	if banned {
+		t.Fatalf("expected expired ban to be removed by Tick")
+	}
+}
+
+// TestRateLimiter_Allow_ReplenishesHighLimits verifies token replenishment at high rates.
+//
+//	limiter := proxy.NewRateLimiter(proxy.RateLimit{MaxConnectionsPerMinute: 120})
+func TestRateLimiter_Allow_ReplenishesHighLimits(t *testing.T) {
+	rl := NewRateLimiter(RateLimit{MaxConnectionsPerMinute: 120, BanDurationSeconds: 1})
+	rl.mu.Lock()
+	rl.bucketByHost["1.2.3.4"] = &tokenBucket{
+		tokens:     0,
+		lastRefill: time.Now().Add(-30 * time.Second),
+	}
+	rl.mu.Unlock()
+
+	if !rl.Allow("1.2.3.4:1234") {
+		t.Fatalf("expected bucket to replenish at 120/min")
+	}
+}
+
+// TestRateLimiter_Disabled_Good verifies a zero-budget limiter allows all connections.
+//
+//	limiter := proxy.NewRateLimiter(proxy.RateLimit{MaxConnectionsPerMinute: 0})
+//	limiter.Allow("any-ip") // always true
+func TestRateLimiter_Disabled_Good(t *testing.T) {
+	rl := NewRateLimiter(RateLimit{MaxConnectionsPerMinute: 0})
+
+	for i := 0; i < 100; i++ {
+		if !rl.Allow("1.2.3.4:3333") {
+			t.Fatalf("expected disabled limiter to allow all connections")
+		}
 	}
 }

reload_test.go

@@ -0,0 +1,404 @@
+package proxy
+
+import (
+	"bufio"
+	"encoding/json"
+	"net"
+	"strings"
+	"testing"
+	"time"
+)
+
+type reloadableSplitter struct {
+	reloads int
+}
+
+func (s *reloadableSplitter) Connect()                    {}
+func (s *reloadableSplitter) OnLogin(event *LoginEvent)   {}
+func (s *reloadableSplitter) OnSubmit(event *SubmitEvent) {}
+func (s *reloadableSplitter) OnClose(event *CloseEvent)   {}
+func (s *reloadableSplitter) Tick(ticks uint64)           {}
+func (s *reloadableSplitter) GC()                         {}
+func (s *reloadableSplitter) Upstreams() UpstreamStats    { return UpstreamStats{} }
+func (s *reloadableSplitter) ReloadPools()                { s.reloads++ }
+
+func TestProxy_Reload_Good(t *testing.T) {
+	original := &Config{
+		Mode:    "nicehash",
+		Workers: WorkersByRigID,
+		Bind:    []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []PoolConfig{{URL: "pool-a.example:3333", Enabled: true}},
+	}
+	p := &Proxy{
+		config:     original,
+		customDiff: NewCustomDiff(1),
+		rateLimit:  NewRateLimiter(RateLimit{}),
+	}
+
+	updated := &Config{
+		Mode:            "simple",
+		Workers:         WorkersByUser,
+		Bind:            []BindAddr{{Host: "0.0.0.0", Port: 4444}},
+		Pools:           []PoolConfig{{URL: "pool-b.example:4444", Enabled: true}},
+		CustomDiff:      50000,
+		AccessPassword:  "secret",
+		CustomDiffStats: true,
+		AlgoExtension:   true,
+		AccessLogFile:   "/tmp/access.log",
+		ReuseTimeout:    30,
+		Retries:         5,
+		RetryPause:      2,
+		Watch:           true,
+		RateLimit:       RateLimit{MaxConnectionsPerMinute: 10, BanDurationSeconds: 60},
+	}
+
+	p.Reload(updated)
+
+	if p.config != original {
+		t.Fatalf("expected reload to preserve the existing config pointer")
+	}
+	if got := p.config.Bind[0]; got.Host != "127.0.0.1" || got.Port != 3333 {
+		t.Fatalf("expected bind addresses to remain unchanged, got %+v", got)
+	}
+	if p.config.Mode != "nicehash" {
+		t.Fatalf("expected mode to remain unchanged, got %q", p.config.Mode)
+	}
+	if p.config.Workers != WorkersByUser {
+		t.Fatalf("expected workers mode to reload, got %q", p.config.Workers)
+	}
+	if got := p.config.Pools[0].URL; got != "pool-b.example:4444" {
+		t.Fatalf("expected pools to reload, got %q", got)
+	}
+	if got := p.customDiff.globalDiff.Load(); got != 50000 {
+		t.Fatalf("expected custom diff to reload, got %d", got)
+	}
+	if !p.rateLimit.IsActive() {
+		t.Fatalf("expected rate limiter to be replaced with active configuration")
+	}
+}
+
+func TestProxy_Reload_WorkersMode_Good(t *testing.T) {
+	miner := &Miner{id: 7, user: "wallet-a", rigID: "rig-a", ip: "10.0.0.7"}
+	workers := NewWorkers(WorkersByRigID, nil)
+	workers.OnLogin(Event{Miner: miner})
+
+	p := &Proxy{
+		config: &Config{
+			Mode:    "nicehash",
+			Workers: WorkersByRigID,
+			Bind:    []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+			Pools:   []PoolConfig{{URL: "pool-a.example:3333", Enabled: true}},
+		},
+		workers: workers,
+		miners:  map[int64]*Miner{miner.id: miner},
+	}
+
+	p.Reload(&Config{
+		Mode:    "nicehash",
+		Workers: WorkersByUser,
+		Bind:    []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []PoolConfig{{URL: "pool-a.example:3333", Enabled: true}},
+	})
+
+	if got := p.WorkersMode(); got != WorkersByUser {
+		t.Fatalf("expected proxy workers mode %q, got %q", WorkersByUser, got)
+	}
+	records := p.WorkerRecords()
+	if len(records) != 1 {
+		t.Fatalf("expected one rebuilt worker record, got %d", len(records))
+	}
+	if got := records[0].Name; got != "wallet-a" {
+		t.Fatalf("expected worker record to rebuild using user mode, got %q", got)
+	}
+}
+
+func TestProxy_Reload_CustomDiff_Good(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := NewMiner(minerConn, 3333, nil)
+	miner.state = MinerStateReady
+	miner.globalDiff = 1000
+	miner.customDiff = 1000
+	miner.currentJob = Job{
+		Blob:   strings.Repeat("0", 160),
+		JobID:  "job-1",
+		Target: "01000000",
+		Algo:   "cn/r",
+	}
+
+	p := &Proxy{
+		config: &Config{
+			Mode:       "nicehash",
+			Workers:    WorkersByRigID,
+			Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+			Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+			CustomDiff: 1000,
+		},
+		customDiff: NewCustomDiff(1000),
+		miners:     map[int64]*Miner{miner.ID(): miner},
+	}
+
+	done := make(chan map[string]any, 1)
+	go func() {
+		line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+		if err != nil {
+			done <- nil
+			return
+		}
+		var payload map[string]any
+		if err := json.Unmarshal(line, &payload); err != nil {
+			done <- nil
+			return
+		}
+		done <- payload
+	}()
+
+	p.Reload(&Config{
+		Mode:       "nicehash",
+		Workers:    WorkersByRigID,
+		Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		CustomDiff: 5000,
+	})
+
+	select {
+	case payload := <-done:
+		if payload == nil {
+			t.Fatal("expected reload to resend the current job with the new custom diff")
+		}
+		params, ok := payload["params"].(map[string]any)
+		if !ok {
+			t.Fatalf("expected job params payload, got %#v", payload["params"])
+		}
+		target, _ := params["target"].(string)
+		if got := (Job{Target: target}).DifficultyFromTarget(); got == 0 || got > 5000 {
+			t.Fatalf("expected resent job difficulty at or below 5000, got %d", got)
+		}
+	case <-time.After(time.Second):
+		t.Fatal("timed out waiting for reload job refresh")
+	}
+
+	if miner.customDiff != 5000 {
+		t.Fatalf("expected active miner custom diff to reload, got %d", miner.customDiff)
+	}
+	if miner.globalDiff != 5000 {
+		t.Fatalf("expected active miner global diff to reload, got %d", miner.globalDiff)
+	}
+}
+
+func TestProxy_Reload_CustomDiff_Bad(t *testing.T) {
+	miner := &Miner{
+		id:                  9,
+		state:               MinerStateReady,
+		globalDiff:          1000,
+		customDiff:          7000,
+		customDiffFromLogin: true,
+		currentJob: Job{
+			Blob:   strings.Repeat("0", 160),
+			JobID:  "job-1",
+			Target: "01000000",
+		},
+	}
+
+	p := &Proxy{
+		config: &Config{
+			Mode:       "nicehash",
+			Workers:    WorkersByRigID,
+			Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+			Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+			CustomDiff: 1000,
+		},
+		customDiff: NewCustomDiff(1000),
+		miners:     map[int64]*Miner{miner.ID(): miner},
+	}
+
+	p.Reload(&Config{
+		Mode:       "nicehash",
+		Workers:    WorkersByRigID,
+		Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		CustomDiff: 5000,
+	})
+
+	if miner.customDiff != 7000 {
+		t.Fatalf("expected login suffix custom diff to be preserved, got %d", miner.customDiff)
+	}
+	if miner.globalDiff != 5000 {
+		t.Fatalf("expected miner global diff to update for future logins, got %d", miner.globalDiff)
+	}
+}
+
+func TestProxy_Reload_CustomDiff_Ugly(t *testing.T) {
+	miner := &Miner{
+		id:         11,
+		state:      MinerStateWaitLogin,
+		globalDiff: 1000,
+		customDiff: 1000,
+	}
+
+	p := &Proxy{
+		config: &Config{
+			Mode:       "nicehash",
+			Workers:    WorkersByRigID,
+			Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+			Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+			CustomDiff: 1000,
+		},
+		customDiff: NewCustomDiff(1000),
+		miners:     map[int64]*Miner{miner.ID(): miner},
+	}
+
+	p.Reload(&Config{
+		Mode:       "nicehash",
+		Workers:    WorkersByRigID,
+		Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		CustomDiff: 0,
+	})
+
+	if miner.customDiff != 0 {
+		t.Fatalf("expected reload to clear the global custom diff for unauthenticated miners, got %d", miner.customDiff)
+	}
+	if miner.globalDiff != 0 {
+		t.Fatalf("expected miner global diff to be cleared, got %d", miner.globalDiff)
+	}
+}
+
+func TestProxy_Reload_UpdatesServers(t *testing.T) {
+	originalLimiter := NewRateLimiter(RateLimit{MaxConnectionsPerMinute: 1})
+	p := &Proxy{
+		config:    &Config{Mode: "nicehash", Workers: WorkersByRigID},
+		rateLimit: originalLimiter,
+		servers: []*Server{
+			{limiter: originalLimiter},
+		},
+	}
+
+	p.Reload(&Config{
+		Mode:          "nicehash",
+		Workers:       WorkersByRigID,
+		Bind:          []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:         []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		RateLimit:     RateLimit{MaxConnectionsPerMinute: 10},
+		AccessLogFile: "",
+	})
+
+	if got := p.servers[0].limiter; got != p.rateLimit {
+		t.Fatalf("expected server limiter to be updated")
+	}
+	if p.rateLimit == originalLimiter {
+		t.Fatalf("expected rate limiter instance to be replaced")
+	}
+}
+
+func TestProxy_Reload_WatchEnabled_Good(t *testing.T) {
+	p := &Proxy{
+		config: &Config{
+			Mode:       "nicehash",
+			Workers:    WorkersByRigID,
+			Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+			Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+			configPath: "/tmp/proxy.json",
+		},
+	}
+
+	p.Reload(&Config{
+		Mode:       "nicehash",
+		Workers:    WorkersByRigID,
+		Bind:       []BindAddr{{Host: "127.0.0.1", Port: 4444}},
+		Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		Watch:      true,
+		configPath: "/tmp/ignored.json",
+	})
+
+	if p.watcher == nil {
+		t.Fatalf("expected reload to create a watcher when watch is enabled")
+	}
+	if got := p.watcher.configPath; got != "/tmp/proxy.json" {
+		t.Fatalf("expected watcher to keep the original config path, got %q", got)
+	}
+	p.watcher.Stop()
+}
+
+func TestProxy_Reload_WatchDisabled_Bad(t *testing.T) {
+	watcher := NewConfigWatcher("/tmp/proxy.json", func(*Config) {})
+	p := &Proxy{
+		config: &Config{
+			Mode:       "nicehash",
+			Workers:    WorkersByRigID,
+			Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+			Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+			configPath: "/tmp/proxy.json",
+			Watch:      true,
+		},
+		watcher: watcher,
+	}
+
+	p.Reload(&Config{
+		Mode:       "nicehash",
+		Workers:    WorkersByRigID,
+		Bind:       []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:      []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		Watch:      false,
+		configPath: "/tmp/ignored.json",
+	})
+
+	if p.watcher != nil {
+		t.Fatalf("expected reload to stop and clear the watcher when watch is disabled")
+	}
+	select {
+	case <-watcher.stopCh:
+	default:
+		t.Fatalf("expected existing watcher to be stopped")
+	}
+}
+
+func TestProxy_Reload_PoolsChanged_ReloadsSplitter_Good(t *testing.T) {
+	splitter := &reloadableSplitter{}
+	p := &Proxy{
+		config: &Config{
+			Mode:    "nicehash",
+			Workers: WorkersByRigID,
+			Bind:    []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+			Pools:   []PoolConfig{{URL: "pool-a.example:3333", Enabled: true}},
+		},
+		splitter: splitter,
+	}
+
+	p.Reload(&Config{
+		Mode:    "nicehash",
+		Workers: WorkersByRigID,
+		Bind:    []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []PoolConfig{{URL: "pool-b.example:3333", Enabled: true}},
+	})
+
+	if splitter.reloads != 1 {
+		t.Fatalf("expected pool reload to reconnect upstreams once, got %d", splitter.reloads)
+	}
+}
+
+func TestProxy_Reload_PoolsUnchanged_DoesNotReloadSplitter_Ugly(t *testing.T) {
+	splitter := &reloadableSplitter{}
+	p := &Proxy{
+		config: &Config{
+			Mode:    "nicehash",
+			Workers: WorkersByRigID,
+			Bind:    []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+			Pools:   []PoolConfig{{URL: "pool-a.example:3333", Enabled: true}},
+		},
+		splitter: splitter,
+	}
+
+	p.Reload(&Config{
+		Mode:    "nicehash",
+		Workers: WorkersByRigID,
+		Bind:    []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:   []PoolConfig{{URL: "pool-a.example:3333", Enabled: true}},
+	})
+
+	if splitter.reloads != 0 {
+		t.Fatalf("expected unchanged pool config to skip reconnect, got %d", splitter.reloads)
+	}
+}

server.go

@@ -7,13 +7,20 @@ import (
 
 // Server listens on one BindAddr and creates a Miner for each accepted connection.
 //
-//	srv, result := proxy.NewServer(bind, tlsCfg, rateLimiter, onAccept)
-//	srv.Start()
+//	srv, result := proxy.NewServer(
+//	    proxy.BindAddr{Host: "0.0.0.0", Port: 3333, TLS: false},
+//	    nil,
+//	    proxy.NewRateLimiter(proxy.RateLimit{MaxConnectionsPerMinute: 30}),
+//	    func(conn net.Conn, port uint16) { _ = conn; _ = port },
+//	)
+//	if result.OK {
+//	    srv.Start()
+//	}
 type Server struct {
-	addr     BindAddr
-	tlsCfg   *tls.Config // nil for plain TCP
-	limiter  *RateLimiter
-	onAccept func(net.Conn, uint16)
-	listener net.Listener
-	done     chan struct{}
+	addr      BindAddr
+	tlsConfig *tls.Config // nil for plain TCP
+	limiter   *RateLimiter
+	onAccept  func(net.Conn, uint16)
+	listener  net.Listener
+	done      chan struct{}
 }

sharelog_impl.go

@@ -0,0 +1,95 @@
+package proxy
+
+import (
+	"os"
+	"strings"
+	"sync"
+	"time"
+)
+
+type shareLogSink struct {
+	path string
+	file *os.File
+	mu   sync.Mutex
+}
+
+func newShareLogSink(path string) *shareLogSink {
+	return &shareLogSink{path: path}
+}
+
+func (l *shareLogSink) SetPath(path string) {
+	if l == nil {
+		return
+	}
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if l.path == path {
+		return
+	}
+	l.path = path
+	if l.file != nil {
+		_ = l.file.Close()
+		l.file = nil
+	}
+}
+
+func (l *shareLogSink) Close() {
+	if l == nil {
+		return
+	}
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if l.file != nil {
+		_ = l.file.Close()
+		l.file = nil
+	}
+}
+
+func (l *shareLogSink) OnAccept(e Event) {
+	if l == nil || e.Miner == nil {
+		return
+	}
+	l.writeLine("ACCEPT", e.Miner.User(), e.Diff, e.Latency, "")
+}
+
+func (l *shareLogSink) OnReject(e Event) {
+	if l == nil || e.Miner == nil {
+		return
+	}
+	l.writeLine("REJECT", e.Miner.User(), 0, 0, e.Error)
+}
+
+func (l *shareLogSink) writeLine(kind, user string, diff uint64, latency uint16, reason string) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if strings.TrimSpace(l.path) == "" {
+		return
+	}
+	if l.file == nil {
+		file, err := os.OpenFile(l.path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
+		if err != nil {
+			return
+		}
+		l.file = file
+	}
+	var builder strings.Builder
+	builder.WriteString(time.Now().UTC().Format(time.RFC3339))
+	builder.WriteByte(' ')
+	builder.WriteString(kind)
+	builder.WriteString("  ")
+	builder.WriteString(user)
+	switch kind {
+	case "ACCEPT":
+		builder.WriteString("  diff=")
+		builder.WriteString(formatUint(diff))
+		builder.WriteString("  latency=")
+		builder.WriteString(formatUint(uint64(latency)))
+		builder.WriteString("ms")
+	case "REJECT":
+		builder.WriteString("  reason=\"")
+		builder.WriteString(reason)
+		builder.WriteString("\"")
+	}
+	builder.WriteByte('\n')
+	_, _ = l.file.WriteString(builder.String())
+}

sharelog_test.go

@@ -0,0 +1,46 @@
+package proxy
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestProxy_ShareLog_WritesOutcomeLines(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "shares.log")
+
+	cfg := &Config{
+		Mode:         "nicehash",
+		Workers:      WorkersByRigID,
+		ShareLogFile: path,
+		Bind:         []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:        []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+	}
+	p, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected valid proxy, got error: %v", result.Error)
+	}
+
+	miner := &Miner{
+		user:  "WALLET",
+		conn:  noopConn{},
+		state: MinerStateReady,
+	}
+	p.events.Dispatch(Event{Type: EventAccept, Miner: miner, Diff: 1234, Latency: 56})
+	p.events.Dispatch(Event{Type: EventReject, Miner: miner, Error: "Invalid nonce"})
+	p.Stop()
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("read share log: %v", err)
+	}
+	text := string(data)
+	if !strings.Contains(text, "ACCEPT  WALLET  diff=1234  latency=56ms") {
+		t.Fatalf("expected ACCEPT line, got %q", text)
+	}
+	if !strings.Contains(text, "REJECT  WALLET  reason=\"Invalid nonce\"") {
+		t.Fatalf("expected REJECT line, got %q", text)
+	}
+}

splitter/nicehash/gc_test.go

@@ -0,0 +1,92 @@
+package nicehash
+
+import (
+	"sync"
+	"testing"
+	"time"
+)
+
+type gcStrategy struct {
+	mu           sync.Mutex
+	disconnected bool
+	active       bool
+}
+
+func (s *gcStrategy) Connect() {}
+
+func (s *gcStrategy) Submit(jobID, nonce, result, algo string) int64 {
+	return 0
+}
+
+func (s *gcStrategy) Disconnect() {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.disconnected = true
+}
+
+func (s *gcStrategy) IsActive() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.active
+}
+
+func TestNonceSplitter_GC_Good(t *testing.T) {
+	strategy := &gcStrategy{active: false}
+	mapper := &NonceMapper{
+		id:       42,
+		storage:  NewNonceStorage(),
+		strategy: strategy,
+		lastUsed: time.Now().Add(-2 * time.Minute),
+		pending:  make(map[int64]SubmitContext),
+	}
+	mapper.storage.slots[0] = -1
+
+	splitter := &NonceSplitter{
+		mappers:    []*NonceMapper{mapper},
+		mapperByID: map[int64]*NonceMapper{mapper.id: mapper},
+	}
+
+	splitter.GC()
+
+	if len(splitter.mappers) != 0 {
+		t.Fatalf("expected idle mapper to be reclaimed, got %d mapper(s)", len(splitter.mappers))
+	}
+	if _, ok := splitter.mapperByID[mapper.id]; ok {
+		t.Fatalf("expected reclaimed mapper to be removed from lookup table")
+	}
+	if !strategy.disconnected {
+		t.Fatalf("expected reclaimed mapper strategy to be disconnected")
+	}
+}
+
+func TestNonceSplitter_GC_Bad(t *testing.T) {
+	var splitter *NonceSplitter
+
+	splitter.GC()
+}
+
+func TestNonceSplitter_GC_Ugly(t *testing.T) {
+	strategy := &gcStrategy{active: true}
+	mapper := &NonceMapper{
+		id:       99,
+		storage:  NewNonceStorage(),
+		strategy: strategy,
+		lastUsed: time.Now().Add(-2 * time.Minute),
+		pending:  make(map[int64]SubmitContext),
+	}
+	mapper.storage.slots[0] = 7
+
+	splitter := &NonceSplitter{
+		mappers:    []*NonceMapper{mapper},
+		mapperByID: map[int64]*NonceMapper{mapper.id: mapper},
+	}
+
+	splitter.GC()
+
+	if len(splitter.mappers) != 1 {
+		t.Fatalf("expected active mapper to remain, got %d mapper(s)", len(splitter.mappers))
+	}
+	if strategy.disconnected {
+		t.Fatalf("expected active mapper to stay connected")
+	}
+}

splitter/nicehash/impl.go

@@ -8,20 +8,20 @@ import (
 )
 
 func init() {
-	proxy.RegisterSplitterFactory("nicehash", func(cfg *proxy.Config, events *proxy.EventBus) proxy.Splitter {
-		return NewNonceSplitter(cfg, events, pool.NewStrategyFactory(cfg))
+	proxy.RegisterSplitterFactory("nicehash", func(config *proxy.Config, eventBus *proxy.EventBus) proxy.Splitter {
+		return NewNonceSplitter(config, eventBus, pool.NewStrategyFactory(config))
 	})
 }
 
 // NewNonceSplitter creates a NiceHash splitter.
-func NewNonceSplitter(cfg *proxy.Config, events *proxy.EventBus, factory pool.StrategyFactory) *NonceSplitter {
+func NewNonceSplitter(config *proxy.Config, eventBus *proxy.EventBus, factory pool.StrategyFactory) *NonceSplitter {
 	if factory == nil {
-		factory = pool.NewStrategyFactory(cfg)
+		factory = pool.NewStrategyFactory(config)
 	}
 	return &NonceSplitter{
-		byID:            make(map[int64]*NonceMapper),
-		cfg:             cfg,
-		events:          events,
+		mapperByID:      make(map[int64]*NonceMapper),
+		config:          config,
+		events:          eventBus,
 		strategyFactory: factory,
 	}
 }
@@ -37,10 +37,7 @@ func (s *NonceSplitter) Connect() {
 		s.addMapperLocked()
 	}
 	for _, mapper := range s.mappers {
-		if mapper.strategy != nil {
-			mapper.strategy.Connect()
-			return
-		}
+		mapper.Start()
 	}
 }
 
@@ -54,14 +51,14 @@ func (s *NonceSplitter) OnLogin(event *proxy.LoginEvent) {
 	event.Miner.SetExtendedNiceHash(true)
 	for _, mapper := range s.mappers {
 		if mapper.Add(event.Miner) {
-			s.byID[mapper.id] = mapper
+			s.mapperByID[mapper.id] = mapper
 			return
 		}
 	}
 	mapper := s.addMapperLocked()
 	if mapper != nil {
 		_ = mapper.Add(event.Miner)
-		s.byID[mapper.id] = mapper
+		s.mapperByID[mapper.id] = mapper
 	}
 }
 
@@ -71,7 +68,7 @@ func (s *NonceSplitter) OnSubmit(event *proxy.SubmitEvent) {
 		return
 	}
 	s.mu.RLock()
-	mapper := s.byID[event.Miner.MapperID()]
+	mapper := s.mapperByID[event.Miner.MapperID()]
 	s.mu.RUnlock()
 	if mapper != nil {
 		mapper.Submit(event)
@@ -84,7 +81,7 @@ func (s *NonceSplitter) OnClose(event *proxy.CloseEvent) {
 		return
 	}
 	s.mu.RLock()
-	mapper := s.byID[event.Miner.MapperID()]
+	mapper := s.mapperByID[event.Miner.MapperID()]
 	s.mu.RUnlock()
 	if mapper != nil {
 		mapper.Remove(event.Miner)
@@ -101,13 +98,17 @@ func (s *NonceSplitter) GC() {
 	now := time.Now()
 	next := s.mappers[:0]
 	for _, mapper := range s.mappers {
+		if mapper == nil || mapper.storage == nil {
+			continue
+		}
 		free, dead, active := mapper.storage.SlotCount()
-		if active == 0 && dead == 0 && now.Sub(mapper.lastUsed) > time.Minute {
+		if active == 0 && now.Sub(mapper.lastUsed) > time.Minute {
 			if mapper.strategy != nil {
 				mapper.strategy.Disconnect()
 			}
-			delete(s.byID, mapper.id)
+			delete(s.mapperByID, mapper.id)
 			_ = free
+			_ = dead
 			continue
 		}
 		next = append(next, mapper)
@@ -116,7 +117,25 @@ func (s *NonceSplitter) GC() {
 }
 
 // Tick is called once per second.
-func (s *NonceSplitter) Tick(ticks uint64) {}
+func (s *NonceSplitter) Tick(ticks uint64) {
+	if s == nil {
+		return
+	}
+	strategies := make([]pool.Strategy, 0, len(s.mappers))
+	s.mu.RLock()
+	for _, mapper := range s.mappers {
+		if mapper == nil || mapper.strategy == nil {
+			continue
+		}
+		strategies = append(strategies, mapper.strategy)
+	}
+	s.mu.RUnlock()
+	for _, strategy := range strategies {
+		if ticker, ok := strategy.(interface{ Tick(uint64) }); ok {
+			ticker.Tick(ticks)
+		}
+	}
+}
 
 // Upstreams returns pool connection counts.
 func (s *NonceSplitter) Upstreams() proxy.UpstreamStats {
@@ -129,40 +148,91 @@ func (s *NonceSplitter) Upstreams() proxy.UpstreamStats {
 	for _, mapper := range s.mappers {
 		if mapper.strategy != nil && mapper.strategy.IsActive() {
 			stats.Active++
-		} else if mapper.suspended > 0 {
+		} else if mapper.suspended > 0 || !mapper.active {
 			stats.Error++
 		}
 	}
-	stats.Total = uint64(len(s.mappers))
+	stats.Total = stats.Active + stats.Sleep + stats.Error
 	return stats
 }
 
+// Disconnect closes all upstream pool connections and forgets the current mapper set.
+func (s *NonceSplitter) Disconnect() {
+	if s == nil {
+		return
+	}
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	for _, mapper := range s.mappers {
+		if mapper != nil && mapper.strategy != nil {
+			mapper.strategy.Disconnect()
+		}
+	}
+	s.mappers = nil
+	s.mapperByID = make(map[int64]*NonceMapper)
+}
+
+// ReloadPools reconnects each mapper strategy using the updated pool list.
+//
+//	s.ReloadPools()
+func (s *NonceSplitter) ReloadPools() {
+	if s == nil {
+		return
+	}
+	strategies := make([]pool.Strategy, 0, len(s.mappers))
+	s.mu.RLock()
+	for _, mapper := range s.mappers {
+		if mapper == nil || mapper.strategy == nil {
+			continue
+		}
+		strategies = append(strategies, mapper.strategy)
+	}
+	s.mu.RUnlock()
+	for _, strategy := range strategies {
+		if reloadable, ok := strategy.(pool.ReloadableStrategy); ok {
+			reloadable.ReloadPools()
+		}
+	}
+}
+
 func (s *NonceSplitter) addMapperLocked() *NonceMapper {
-	id := s.seq
-	s.seq++
-	mapper := NewNonceMapper(id, s.cfg, nil)
+	id := s.nextMapperID
+	s.nextMapperID++
+	mapper := NewNonceMapper(id, s.config, nil)
 	mapper.events = s.events
 	mapper.lastUsed = time.Now()
 	mapper.strategy = s.strategyFactory(mapper)
 	s.mappers = append(s.mappers, mapper)
-	if s.byID == nil {
-		s.byID = make(map[int64]*NonceMapper)
+	if s.mapperByID == nil {
+		s.mapperByID = make(map[int64]*NonceMapper)
 	}
-	s.byID[mapper.id] = mapper
+	s.mapperByID[mapper.id] = mapper
+	mapper.Start()
 	return mapper
 }
 
 // NewNonceMapper creates a mapper for one upstream connection.
-func NewNonceMapper(id int64, cfg *proxy.Config, strategy pool.Strategy) *NonceMapper {
+func NewNonceMapper(id int64, config *proxy.Config, strategy pool.Strategy) *NonceMapper {
 	return &NonceMapper{
 		id:       id,
 		storage:  NewNonceStorage(),
 		strategy: strategy,
 		pending:  make(map[int64]SubmitContext),
-		cfg:      cfg,
+		config:   config,
 	}
 }
 
+// Start connects the mapper's upstream strategy once.
+func (m *NonceMapper) Start() {
+	if m == nil || m.strategy == nil {
+		return
+	}
+	m.startOnce.Do(func() {
+		m.lastUsed = time.Now()
+		m.strategy.Connect()
+	})
+}
+
 // Add assigns a miner to a free slot.
 func (m *NonceMapper) Add(miner *proxy.Miner) bool {
 	if m == nil || miner == nil {
@@ -179,7 +249,7 @@ func (m *NonceMapper) Add(miner *proxy.Miner) bool {
 		job := m.storage.job
 		m.storage.mu.Unlock()
 		if job.IsValid() {
-			miner.ForwardJob(job, job.Algo)
+			miner.SetCurrentJob(job)
 		}
 	}
 	return ok
@@ -212,14 +282,34 @@ func (m *NonceMapper) Submit(event *proxy.SubmitEvent) {
 	if jobID == "" {
 		jobID = job.JobID
 	}
-	if jobID == "" || (jobID != job.JobID && jobID != prevJob.JobID) {
+	valid := m.storage.IsValidJobID(jobID)
+	if jobID == "" || !valid {
+		m.rejectInvalidJobLocked(event, job)
 		return
 	}
+	submissionJob := job
+	if jobID == prevJob.JobID && prevJob.JobID != "" {
+		submissionJob = prevJob
+	}
 	seq := m.strategy.Submit(jobID, event.Nonce, event.Result, event.Algo)
-	m.pending[seq] = SubmitContext{RequestID: event.RequestID, MinerID: event.Miner.ID(), JobID: jobID}
+	m.pending[seq] = SubmitContext{
+		RequestID: event.RequestID,
+		MinerID:   event.Miner.ID(),
+		JobID:     jobID,
+		Diff:      proxy.EffectiveShareDifficulty(submissionJob, event.Miner),
+		StartedAt: time.Now(),
+	}
 	m.lastUsed = time.Now()
 }
 
+func (m *NonceMapper) rejectInvalidJobLocked(event *proxy.SubmitEvent, job proxy.Job) {
+	event.Miner.ReplyWithError(event.RequestID, "Invalid job id")
+	if m.events != nil {
+		jobCopy := job
+		m.events.Dispatch(proxy.Event{Type: proxy.EventReject, Miner: event.Miner, Job: &jobCopy, Error: "Invalid job id"})
+	}
+}
+
 // IsActive reports whether the mapper has received a valid job.
 func (m *NonceMapper) IsActive() bool {
 	if m == nil {
@@ -258,24 +348,40 @@ func (m *NonceMapper) OnResultAccepted(sequence int64, accepted bool, errorMessa
 	job := m.storage.job
 	prevJob := m.storage.prevJob
 	m.storage.mu.Unlock()
-	expired := ctx.JobID != "" && ctx.JobID == prevJob.JobID && ctx.JobID != job.JobID
+	job, expired := resolveSubmissionJob(ctx.JobID, job, prevJob)
 	m.mu.Unlock()
 	if !ok || miner == nil {
 		return
 	}
+	latency := uint16(0)
+	if !ctx.StartedAt.IsZero() {
+		elapsed := time.Since(ctx.StartedAt).Milliseconds()
+		if elapsed > int64(^uint16(0)) {
+			latency = ^uint16(0)
+		} else {
+			latency = uint16(elapsed)
+		}
+	}
 	if accepted {
 		miner.Success(ctx.RequestID, "OK")
 		if m.events != nil {
-			m.events.Dispatch(proxy.Event{Type: proxy.EventAccept, Miner: miner, Job: &job, Diff: job.DifficultyFromTarget(), Latency: 0, Expired: expired})
+			m.events.Dispatch(proxy.Event{Type: proxy.EventAccept, Miner: miner, Job: &job, Diff: ctx.Diff, Latency: latency, Expired: expired})
 		}
 		return
 	}
 	miner.ReplyWithError(ctx.RequestID, errorMessage)
 	if m.events != nil {
-		m.events.Dispatch(proxy.Event{Type: proxy.EventReject, Miner: miner, Job: &job, Diff: job.DifficultyFromTarget(), Error: errorMessage})
+		m.events.Dispatch(proxy.Event{Type: proxy.EventReject, Miner: miner, Job: &job, Diff: ctx.Diff, Error: errorMessage, Latency: latency})
 	}
 }
 
+func resolveSubmissionJob(jobID string, currentJob, previousJob proxy.Job) (proxy.Job, bool) {
+	if jobID != "" && jobID == previousJob.JobID && jobID != currentJob.JobID {
+		return previousJob, true
+	}
+	return currentJob, false
+}
+
 func (m *NonceMapper) OnDisconnect() {
 	if m == nil {
 		return
@@ -286,12 +392,16 @@ func (m *NonceMapper) OnDisconnect() {
 	m.suspended++
 }
 
-// NewNonceStorage creates an empty slot table.
+// NewNonceStorage creates a 256-slot table ready for round-robin miner allocation.
+//
+//	storage := nicehash.NewNonceStorage()
 func NewNonceStorage() *NonceStorage {
 	return &NonceStorage{miners: make(map[int64]*proxy.Miner)}
 }
 
-// Add finds the next free slot.
+// Add assigns the next free slot, such as 0x2a, to one miner.
+//
+//	ok := storage.Add(&proxy.Miner{})
 func (s *NonceStorage) Add(miner *proxy.Miner) bool {
 	if s == nil || miner == nil {
 		return false
@@ -312,7 +422,9 @@ func (s *NonceStorage) Add(miner *proxy.Miner) bool {
 	return false
 }
 
-// Remove marks a slot as dead.
+// Remove marks one miner's slot as dead until the next SetJob call.
+//
+//	storage.Remove(miner)
 func (s *NonceStorage) Remove(miner *proxy.Miner) {
 	if s == nil || miner == nil {
 		return
@@ -326,7 +438,9 @@ func (s *NonceStorage) Remove(miner *proxy.Miner) {
 	delete(s.miners, miner.ID())
 }
 
-// SetJob replaces the current job and sends it to active miners.
+// SetJob broadcasts one pool job to all active miners and clears dead slots.
+//
+//	storage.SetJob(proxy.Job{Blob: strings.Repeat("0", 160), JobID: "job-1"})
 func (s *NonceStorage) SetJob(job proxy.Job) {
 	if s == nil || !job.IsValid() {
 		return
@@ -352,17 +466,31 @@ func (s *NonceStorage) SetJob(job proxy.Job) {
 	}
 }
 
-// IsValidJobID returns true if the id matches the current or previous job.
+// IsValidJobID accepts the current job, or the immediately previous one after a pool roll.
+//
+//	if !storage.IsValidJobID("job-1") { return }
 func (s *NonceStorage) IsValidJobID(id string) bool {
 	if s == nil {
 		return false
 	}
 	s.mu.Lock()
 	defer s.mu.Unlock()
-	return id != "" && (id == s.job.JobID || id == s.prevJob.JobID)
+	if id == "" {
+		return false
+	}
+	if id == s.job.JobID {
+		return true
+	}
+	if id == s.prevJob.JobID && s.prevJob.JobID != "" {
+		s.expired++
+		return true
+	}
+	return false
 }
 
-// SlotCount returns free, dead, and active counts.
+// SlotCount returns free, dead, and active slot counts such as 254, 1, 1.
+//
+//	free, dead, active := storage.SlotCount()
 func (s *NonceStorage) SlotCount() (free, dead, active int) {
 	if s == nil {
 		return 0, 0, 0

splitter/nicehash/mapper.go

@@ -18,11 +18,12 @@ type NonceMapper struct {
 	storage   *NonceStorage
 	strategy  pool.Strategy           // manages pool client lifecycle and failover
 	pending   map[int64]SubmitContext // sequence → {requestID, minerID}
-	cfg       *proxy.Config
+	config    *proxy.Config
 	events    *proxy.EventBus
 	active    bool // true once pool has sent at least one job
 	suspended int  // > 0 when pool connection is in error/reconnecting
 	lastUsed  time.Time
+	startOnce sync.Once
 	mu        sync.Mutex
 }
 
@@ -33,4 +34,6 @@ type SubmitContext struct {
 	RequestID int64 // JSON-RPC id from the miner's submit request
 	MinerID   int64 // miner that submitted
 	JobID     string
+	Diff      uint64
+	StartedAt time.Time
 }

splitter/nicehash/mapper_start_test.go

@@ -0,0 +1,243 @@
+package nicehash
+
+import (
+	"bufio"
+	"encoding/json"
+	"net"
+	"sync"
+	"testing"
+	"time"
+
+	"dappco.re/go/proxy"
+)
+
+type startCountingStrategy struct {
+	mu      sync.Mutex
+	connect int
+}
+
+func (s *startCountingStrategy) Connect() {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.connect++
+}
+
+func (s *startCountingStrategy) Submit(jobID, nonce, result, algo string) int64 {
+	return 0
+}
+
+func (s *startCountingStrategy) Disconnect() {}
+
+func (s *startCountingStrategy) IsActive() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.connect > 0
+}
+
+type discardConn struct{}
+
+func (discardConn) Read([]byte) (int, error)         { return 0, nil }
+func (discardConn) Write(p []byte) (int, error)      { return len(p), nil }
+func (discardConn) Close() error                     { return nil }
+func (discardConn) LocalAddr() net.Addr              { return nil }
+func (discardConn) RemoteAddr() net.Addr             { return nil }
+func (discardConn) SetDeadline(time.Time) error      { return nil }
+func (discardConn) SetReadDeadline(time.Time) error  { return nil }
+func (discardConn) SetWriteDeadline(time.Time) error { return nil }
+
+func TestMapper_Start_Good(t *testing.T) {
+	strategy := &startCountingStrategy{}
+	mapper := NewNonceMapper(1, &proxy.Config{}, strategy)
+
+	mapper.Start()
+
+	if strategy.connect != 1 {
+		t.Fatalf("expected one connect call, got %d", strategy.connect)
+	}
+}
+
+func TestMapper_Start_Bad(t *testing.T) {
+	mapper := NewNonceMapper(1, &proxy.Config{}, nil)
+
+	mapper.Start()
+}
+
+func TestMapper_Start_Ugly(t *testing.T) {
+	strategy := &startCountingStrategy{}
+	mapper := NewNonceMapper(1, &proxy.Config{}, strategy)
+
+	mapper.Start()
+	mapper.Start()
+
+	if strategy.connect != 1 {
+		t.Fatalf("expected Start to be idempotent, got %d connect calls", strategy.connect)
+	}
+}
+
+func TestMapper_Submit_InvalidJob_Good(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := proxy.NewMiner(minerConn, 3333, nil)
+	miner.SetID(7)
+	strategy := &startCountingStrategy{}
+	mapper := NewNonceMapper(1, &proxy.Config{}, strategy)
+	mapper.storage.job = proxy.Job{JobID: "job-1", Blob: "blob", Target: "b88d0600"}
+
+	done := make(chan struct{})
+	go func() {
+		mapper.Submit(&proxy.SubmitEvent{
+			Miner:     miner,
+			JobID:     "job-missing",
+			Nonce:     "deadbeef",
+			Result:    "hash",
+			RequestID: 42,
+		})
+		close(done)
+	}()
+
+	line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read error reply: %v", err)
+	}
+	<-done
+
+	var payload struct {
+		ID    float64 `json:"id"`
+		Error struct {
+			Message string `json:"message"`
+		} `json:"error"`
+	}
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal error reply: %v", err)
+	}
+	if payload.ID != 42 {
+		t.Fatalf("expected request id 42, got %v", payload.ID)
+	}
+	if payload.Error.Message != "Invalid job id" {
+		t.Fatalf("expected invalid job error, got %q", payload.Error.Message)
+	}
+	if len(mapper.pending) != 0 {
+		t.Fatalf("expected invalid submit not to create a pending entry")
+	}
+}
+
+func TestMapper_OnResultAccepted_ExpiredUsesPreviousJob(t *testing.T) {
+	bus := proxy.NewEventBus()
+	events := make(chan proxy.Event, 1)
+	bus.Subscribe(proxy.EventAccept, func(e proxy.Event) {
+		events <- e
+	})
+
+	miner := proxy.NewMiner(discardConn{}, 3333, nil)
+	miner.SetID(7)
+	mapper := NewNonceMapper(1, &proxy.Config{}, &startCountingStrategy{})
+	mapper.events = bus
+	mapper.storage.job = proxy.Job{JobID: "job-new", Blob: "blob-new", Target: "b88d0600"}
+	mapper.storage.prevJob = proxy.Job{JobID: "job-old", Blob: "blob-old", Target: "b88d0600"}
+	mapper.storage.miners[miner.ID()] = miner
+	if !mapper.storage.IsValidJobID("job-old") {
+		t.Fatal("expected previous job to validate before result handling")
+	}
+	mapper.pending[9] = SubmitContext{
+		RequestID: 42,
+		MinerID:   miner.ID(),
+		JobID:     "job-old",
+		StartedAt: time.Now(),
+	}
+
+	mapper.OnResultAccepted(9, true, "")
+
+	if got := mapper.storage.expired; got != 1 {
+		t.Fatalf("expected one expired validation, got %d", got)
+	}
+
+	select {
+	case event := <-events:
+		if !event.Expired {
+			t.Fatalf("expected expired share to be flagged")
+		}
+		if event.Job == nil || event.Job.JobID != "job-old" {
+			t.Fatalf("expected previous job to be attached, got %+v", event.Job)
+		}
+	case <-time.After(time.Second):
+		t.Fatal("expected accept event")
+	}
+}
+
+func TestMapper_Submit_ExpiredJobUsesPreviousDifficulty(t *testing.T) {
+	miner := proxy.NewMiner(discardConn{}, 3333, nil)
+	miner.SetID(9)
+
+	strategy := &submitCaptureStrategy{}
+	mapper := NewNonceMapper(1, &proxy.Config{}, strategy)
+	mapper.storage.job = proxy.Job{JobID: "job-new", Blob: "blob-new", Target: "ffffffff"}
+	mapper.storage.prevJob = proxy.Job{JobID: "job-old", Blob: "blob-old", Target: "b88d0600"}
+	mapper.storage.miners[miner.ID()] = miner
+
+	mapper.Submit(&proxy.SubmitEvent{
+		Miner:     miner,
+		JobID:     "job-old",
+		Nonce:     "deadbeef",
+		Result:    "hash",
+		RequestID: 88,
+	})
+
+	ctx, ok := mapper.pending[strategy.seq]
+	if !ok {
+		t.Fatal("expected pending submit context for expired job")
+	}
+	want := mapper.storage.prevJob.DifficultyFromTarget()
+	if ctx.Diff != want {
+		t.Fatalf("expected previous-job difficulty %d, got %d", want, ctx.Diff)
+	}
+}
+
+type submitCaptureStrategy struct {
+	seq int64
+}
+
+func (s *submitCaptureStrategy) Connect() {}
+
+func (s *submitCaptureStrategy) Submit(jobID, nonce, result, algo string) int64 {
+	s.seq++
+	return s.seq
+}
+
+func (s *submitCaptureStrategy) Disconnect() {}
+
+func (s *submitCaptureStrategy) IsActive() bool { return true }
+
+func TestMapper_OnResultAccepted_CustomDiffUsesEffectiveDifficulty(t *testing.T) {
+	bus := proxy.NewEventBus()
+	events := make(chan proxy.Event, 1)
+	bus.Subscribe(proxy.EventAccept, func(e proxy.Event) {
+		events <- e
+	})
+
+	miner := proxy.NewMiner(discardConn{}, 3333, nil)
+	miner.SetID(8)
+	mapper := NewNonceMapper(1, &proxy.Config{}, &startCountingStrategy{})
+	mapper.events = bus
+	mapper.storage.job = proxy.Job{JobID: "job-new", Blob: "blob-new", Target: "b88d0600"}
+	mapper.storage.miners[miner.ID()] = miner
+	mapper.pending[10] = SubmitContext{
+		RequestID: 77,
+		MinerID:   miner.ID(),
+		JobID:     "job-new",
+		Diff:      25000,
+		StartedAt: time.Now(),
+	}
+
+	mapper.OnResultAccepted(10, true, "")
+
+	select {
+	case event := <-events:
+		if event.Diff != 25000 {
+			t.Fatalf("expected effective difficulty 25000, got %d", event.Diff)
+		}
+	case <-time.After(time.Second):
+		t.Fatal("expected accept event")
+	}
+}

splitter/nicehash/reload_test.go

@@ -0,0 +1,67 @@
+package nicehash
+
+import (
+	"testing"
+
+	"dappco.re/go/proxy"
+	"dappco.re/go/proxy/pool"
+)
+
+type reloadableStrategy struct {
+	reloads int
+}
+
+func (s *reloadableStrategy) Connect()                                       {}
+func (s *reloadableStrategy) Submit(jobID, nonce, result, algo string) int64 { return 0 }
+func (s *reloadableStrategy) Disconnect()                                    {}
+func (s *reloadableStrategy) IsActive() bool                                 { return true }
+func (s *reloadableStrategy) ReloadPools()                                   { s.reloads++ }
+
+var _ pool.ReloadableStrategy = (*reloadableStrategy)(nil)
+
+func TestNonceSplitter_ReloadPools_Good(t *testing.T) {
+	strategy := &reloadableStrategy{}
+	splitter := &NonceSplitter{
+		mappers: []*NonceMapper{
+			{strategy: strategy},
+		},
+	}
+
+	splitter.ReloadPools()
+
+	if strategy.reloads != 1 {
+		t.Fatalf("expected mapper strategy to reload once, got %d", strategy.reloads)
+	}
+}
+
+func TestNonceSplitter_ReloadPools_Bad(t *testing.T) {
+	splitter := &NonceSplitter{
+		mappers: []*NonceMapper{
+			{strategy: nil},
+		},
+	}
+
+	splitter.ReloadPools()
+}
+
+func TestNonceSplitter_ReloadPools_Ugly(t *testing.T) {
+	splitter := NewNonceSplitter(&proxy.Config{}, proxy.NewEventBus(), func(listener pool.StratumListener) pool.Strategy {
+		return &reloadableStrategy{}
+	})
+	splitter.mappers = []*NonceMapper{
+		{strategy: &reloadableStrategy{}},
+		{strategy: &reloadableStrategy{}},
+	}
+
+	splitter.ReloadPools()
+
+	for index, mapper := range splitter.mappers {
+		strategy, ok := mapper.strategy.(*reloadableStrategy)
+		if !ok {
+			t.Fatalf("expected reloadable strategy at mapper %d", index)
+		}
+		if strategy.reloads != 1 {
+			t.Fatalf("expected mapper %d to reload once, got %d", index, strategy.reloads)
+		}
+	}
+}

splitter/nicehash/splitter.go

@@ -23,10 +23,10 @@ import (
 //	s.Connect()
 type NonceSplitter struct {
 	mappers         []*NonceMapper
-	byID            map[int64]*NonceMapper
-	cfg             *proxy.Config
+	mapperByID      map[int64]*NonceMapper
+	config          *proxy.Config
 	events          *proxy.EventBus
 	strategyFactory pool.StrategyFactory
 	mu              sync.RWMutex
-	seq             int64
+	nextMapperID    int64
 }

splitter/nicehash/storage.go

@@ -20,6 +20,7 @@ type NonceStorage struct {
 	miners  map[int64]*proxy.Miner // minerID → Miner pointer for active miners
 	job     proxy.Job              // current job from pool
 	prevJob proxy.Job              // previous job (for stale submit validation)
-	cursor  int                    // search starts here (round-robin allocation)
+	expired uint64
+	cursor  int // search starts here (round-robin allocation)
 	mu      sync.Mutex
 }

splitter/nicehash/storage_test.go

@@ -6,21 +6,155 @@ import (
 	"dappco.re/go/proxy"
 )
 
-func TestNonceStorage_AddAndRemove(t *testing.T) {
+// TestStorage_Add_Good verifies 256 sequential Add calls fill all slots with unique FixedByte values.
+//
+//	storage := nicehash.NewNonceStorage()
+//	for i := 0; i < 256; i++ {
+//	    m := &proxy.Miner{}
+//	    m.SetID(int64(i + 1))
+//	    ok := storage.Add(m) // true for all 256
+//	}
+func TestStorage_Add_Good(t *testing.T) {
+	storage := NewNonceStorage()
+	seen := make(map[uint8]bool)
+	for i := 0; i < 256; i++ {
+		m := &proxy.Miner{}
+		m.SetID(int64(i + 1))
+		ok := storage.Add(m)
+		if !ok {
+			t.Fatalf("expected add %d to succeed", i)
+		}
+		if seen[m.FixedByte()] {
+			t.Fatalf("duplicate fixed byte %d at add %d", m.FixedByte(), i)
+		}
+		seen[m.FixedByte()] = true
+	}
+}
+
+// TestStorage_Add_Bad verifies the 257th Add returns false when all 256 slots are occupied.
+//
+//	storage := nicehash.NewNonceStorage()
+//	// fill 256 slots...
+//	ok := storage.Add(overflowMiner) // false — table is full
+func TestStorage_Add_Bad(t *testing.T) {
+	storage := NewNonceStorage()
+	for i := 0; i < 256; i++ {
+		m := &proxy.Miner{}
+		m.SetID(int64(i + 1))
+		storage.Add(m)
+	}
+
+	overflow := &proxy.Miner{}
+	overflow.SetID(257)
+	if storage.Add(overflow) {
+		t.Fatalf("expected 257th add to fail when table is full")
+	}
+}
+
+// TestStorage_Add_Ugly verifies that a removed slot (dead) is reclaimed after SetJob clears it.
+//
+//	storage := nicehash.NewNonceStorage()
+//	storage.Add(miner)
+//	storage.Remove(miner) // slot becomes dead (-minerID)
+//	storage.SetJob(job)   // dead slots cleared to 0
+//	storage.Add(newMiner) // reclaimed slot succeeds
+func TestStorage_Add_Ugly(t *testing.T) {
 	storage := NewNonceStorage()
 	miner := &proxy.Miner{}
 	miner.SetID(1)
 
 	if !storage.Add(miner) {
-		t.Fatalf("expected add to succeed")
-	}
-	if miner.FixedByte() != 0 {
-		t.Fatalf("expected first slot to be 0, got %d", miner.FixedByte())
+		t.Fatalf("expected first add to succeed")
 	}
 
 	storage.Remove(miner)
 	free, dead, active := storage.SlotCount()
-	if free != 255 || dead != 1 || active != 0 {
-		t.Fatalf("unexpected slot counts: free=%d dead=%d active=%d", free, dead, active)
+	if dead != 1 || active != 0 {
+		t.Fatalf("expected 1 dead slot, got free=%d dead=%d active=%d", free, dead, active)
+	}
+
+	// SetJob clears dead slots
+	storage.SetJob(proxy.Job{Blob: "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000", JobID: "job-1"})
+	free, dead, active = storage.SlotCount()
+	if dead != 0 {
+		t.Fatalf("expected dead slots cleared after SetJob, got %d", dead)
+	}
+
+	// Reclaim the slot
+	newMiner := &proxy.Miner{}
+	newMiner.SetID(2)
+	if !storage.Add(newMiner) {
+		t.Fatalf("expected reclaimed slot add to succeed")
+	}
+}
+
+// TestStorage_IsValidJobID_Good verifies the current job ID is accepted.
+//
+//	storage := nicehash.NewNonceStorage()
+//	storage.SetJob(proxy.Job{JobID: "job-2", Blob: "..."})
+//	storage.IsValidJobID("job-2") // true
+func TestStorage_IsValidJobID_Good(t *testing.T) {
+	storage := NewNonceStorage()
+	storage.SetJob(proxy.Job{
+		JobID: "job-1",
+		Blob:  "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+	})
+
+	if !storage.IsValidJobID("job-1") {
+		t.Fatalf("expected current job to be valid")
+	}
+}
+
+// TestStorage_IsValidJobID_Bad verifies an unknown job ID is rejected.
+//
+//	storage := nicehash.NewNonceStorage()
+//	storage.IsValidJobID("nonexistent") // false
+func TestStorage_IsValidJobID_Bad(t *testing.T) {
+	storage := NewNonceStorage()
+	storage.SetJob(proxy.Job{
+		JobID: "job-1",
+		Blob:  "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+	})
+
+	if storage.IsValidJobID("nonexistent") {
+		t.Fatalf("expected unknown job id to be invalid")
+	}
+	if storage.IsValidJobID("") {
+		t.Fatalf("expected empty job id to be invalid")
+	}
+}
+
+// TestStorage_IsValidJobID_Ugly verifies the previous job ID is accepted but counts as expired.
+//
+//	storage := nicehash.NewNonceStorage()
+//	// job-1 is current, job-2 pushes job-1 to previous
+//	storage.IsValidJobID("job-1") // true (but expired counter increments)
+func TestStorage_IsValidJobID_Ugly(t *testing.T) {
+	storage := NewNonceStorage()
+	blob160 := "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
+
+	storage.SetJob(proxy.Job{JobID: "job-1", Blob: blob160, ClientID: "session-1"})
+	storage.SetJob(proxy.Job{JobID: "job-2", Blob: blob160, ClientID: "session-1"})
+
+	if !storage.IsValidJobID("job-2") {
+		t.Fatalf("expected current job to be valid")
+	}
+	if !storage.IsValidJobID("job-1") {
+		t.Fatalf("expected previous job to remain valid")
+	}
+	if storage.expired != 1 {
+		t.Fatalf("expected one expired job validation, got %d", storage.expired)
+	}
+}
+
+// TestStorage_SlotCount_Good verifies free/dead/active counts on a fresh storage.
+//
+//	storage := nicehash.NewNonceStorage()
+//	free, dead, active := storage.SlotCount() // 256, 0, 0
+func TestStorage_SlotCount_Good(t *testing.T) {
+	storage := NewNonceStorage()
+	free, dead, active := storage.SlotCount()
+	if free != 256 || dead != 0 || active != 0 {
+		t.Fatalf("expected 256/0/0, got free=%d dead=%d active=%d", free, dead, active)
 	}
 }

splitter/nicehash/upstreams_test.go

@@ -0,0 +1,69 @@
+package nicehash
+
+import (
+	"testing"
+
+	"dappco.re/go/proxy"
+)
+
+type upstreamStateStrategy struct {
+	active bool
+}
+
+func (s *upstreamStateStrategy) Connect() {}
+
+func (s *upstreamStateStrategy) Submit(jobID, nonce, result, algo string) int64 {
+	return 0
+}
+
+func (s *upstreamStateStrategy) Disconnect() {}
+
+func (s *upstreamStateStrategy) IsActive() bool { return s.active }
+
+func TestNonceSplitter_Upstreams_Good(t *testing.T) {
+	splitter := &NonceSplitter{
+		mappers: []*NonceMapper{
+			{strategy: &upstreamStateStrategy{active: true}, active: true},
+			{strategy: &upstreamStateStrategy{active: false}, active: false, suspended: 1},
+		},
+	}
+
+	stats := splitter.Upstreams()
+
+	if stats.Active != 1 {
+		t.Fatalf("expected one active upstream, got %d", stats.Active)
+	}
+	if stats.Error != 1 {
+		t.Fatalf("expected one error upstream, got %d", stats.Error)
+	}
+	if stats.Total != 2 {
+		t.Fatalf("expected total to equal active + sleep + error, got %d", stats.Total)
+	}
+}
+
+func TestNonceSplitter_Upstreams_Bad(t *testing.T) {
+	var splitter *NonceSplitter
+
+	stats := splitter.Upstreams()
+
+	if stats != (proxy.UpstreamStats{}) {
+		t.Fatalf("expected zero-value stats for nil splitter, got %+v", stats)
+	}
+}
+
+func TestNonceSplitter_Upstreams_Ugly(t *testing.T) {
+	splitter := &NonceSplitter{
+		mappers: []*NonceMapper{
+			{strategy: &upstreamStateStrategy{active: false}, active: false},
+		},
+	}
+
+	stats := splitter.Upstreams()
+
+	if stats.Error != 1 {
+		t.Fatalf("expected an unready mapper to be counted as error, got %+v", stats)
+	}
+	if stats.Total != 1 {
+		t.Fatalf("expected total to remain internally consistent, got %+v", stats)
+	}
+}

splitter/simple/impl.go

@@ -8,21 +8,21 @@ import (
 )
 
 func init() {
-	proxy.RegisterSplitterFactory("simple", func(cfg *proxy.Config, events *proxy.EventBus) proxy.Splitter {
-		return NewSimpleSplitter(cfg, events, pool.NewStrategyFactory(cfg))
+	proxy.RegisterSplitterFactory("simple", func(config *proxy.Config, eventBus *proxy.EventBus) proxy.Splitter {
+		return NewSimpleSplitter(config, eventBus, pool.NewStrategyFactory(config))
 	})
 }
 
 // NewSimpleSplitter creates the passthrough splitter.
-func NewSimpleSplitter(cfg *proxy.Config, events *proxy.EventBus, factory pool.StrategyFactory) *SimpleSplitter {
+func NewSimpleSplitter(config *proxy.Config, eventBus *proxy.EventBus, factory pool.StrategyFactory) *SimpleSplitter {
 	if factory == nil {
-		factory = pool.NewStrategyFactory(cfg)
+		factory = pool.NewStrategyFactory(config)
 	}
 	return &SimpleSplitter{
 		active:  make(map[int64]*SimpleMapper),
 		idle:    make(map[int64]*SimpleMapper),
-		cfg:     cfg,
-		events:  events,
+		config:  config,
+		events:  eventBus,
 		factory: factory,
 	}
 }
@@ -53,16 +53,20 @@ func (s *SimpleSplitter) OnLogin(event *proxy.LoginEvent) {
 	}
 	s.mu.Lock()
 	defer s.mu.Unlock()
+	now := time.Now()
 
-	if s.cfg.ReuseTimeout > 0 {
+	if s.config.ReuseTimeout > 0 {
 		for id, mapper := range s.idle {
-			if mapper.strategy != nil && mapper.strategy.IsActive() {
+			if mapper.strategy != nil && mapper.strategy.IsActive() && !mapper.idleAt.IsZero() && now.Sub(mapper.idleAt) <= time.Duration(s.config.ReuseTimeout)*time.Second {
 				delete(s.idle, id)
 				mapper.miner = event.Miner
 				mapper.idleAt = time.Time{}
 				mapper.stopped = false
 				s.active[event.Miner.ID()] = mapper
 				event.Miner.SetRouteID(mapper.id)
+				if mapper.currentJob.IsValid() {
+					event.Miner.SetCurrentJob(mapper.currentJob)
+				}
 				return
 			}
 		}
@@ -83,7 +87,7 @@ func (s *SimpleSplitter) OnSubmit(event *proxy.SubmitEvent) {
 		return
 	}
 	s.mu.Lock()
-	mapper := s.active[event.Miner.ID()]
+	mapper := s.activeMapperByRouteIDLocked(event.Miner.RouteID())
 	s.mu.Unlock()
 	if mapper != nil {
 		mapper.Submit(event)
@@ -105,7 +109,7 @@ func (s *SimpleSplitter) OnClose(event *proxy.CloseEvent) {
 	mapper.miner = nil
 	mapper.idleAt = time.Now()
 	event.Miner.SetRouteID(-1)
-	if s.cfg.ReuseTimeout > 0 {
+	if s.config.ReuseTimeout > 0 {
 		s.idle[mapper.id] = mapper
 		return
 	}
@@ -124,7 +128,7 @@ func (s *SimpleSplitter) GC() {
 	defer s.mu.Unlock()
 	now := time.Now()
 	for id, mapper := range s.idle {
-		if mapper.stopped || (s.cfg.ReuseTimeout > 0 && now.Sub(mapper.idleAt) > time.Duration(s.cfg.ReuseTimeout)*time.Second) {
+		if mapper.stopped || (s.config.ReuseTimeout > 0 && now.Sub(mapper.idleAt) > time.Duration(s.config.ReuseTimeout)*time.Second) {
 			if mapper.strategy != nil {
 				mapper.strategy.Disconnect()
 			}
@@ -133,8 +137,31 @@ func (s *SimpleSplitter) GC() {
 	}
 }
 
-// Tick is a no-op for simple mode.
-func (s *SimpleSplitter) Tick(ticks uint64) {}
+// Tick advances timeout checks in simple mode.
+func (s *SimpleSplitter) Tick(ticks uint64) {
+	if s == nil {
+		return
+	}
+	strategies := make([]pool.Strategy, 0, len(s.active)+len(s.idle))
+	s.mu.Lock()
+	for _, mapper := range s.active {
+		if mapper != nil && mapper.strategy != nil {
+			strategies = append(strategies, mapper.strategy)
+		}
+	}
+	for _, mapper := range s.idle {
+		if mapper != nil && mapper.strategy != nil {
+			strategies = append(strategies, mapper.strategy)
+		}
+	}
+	s.mu.Unlock()
+	for _, strategy := range strategies {
+		if ticker, ok := strategy.(interface{ Tick(uint64) }); ok {
+			ticker.Tick(ticks)
+		}
+	}
+	s.GC()
+}
 
 // Upstreams returns active/idle/error counts.
 func (s *SimpleSplitter) Upstreams() proxy.UpstreamStats {
@@ -144,20 +171,85 @@ func (s *SimpleSplitter) Upstreams() proxy.UpstreamStats {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 	var stats proxy.UpstreamStats
-	stats.Active = uint64(len(s.active))
-	stats.Sleep = uint64(len(s.idle))
-	stats.Total = stats.Active + stats.Sleep
+	for _, mapper := range s.active {
+		if mapper == nil {
+			continue
+		}
+		if mapper.stopped || mapper.strategy == nil || !mapper.strategy.IsActive() {
+			stats.Error++
+			continue
+		}
+		stats.Active++
+	}
+	for _, mapper := range s.idle {
+		if mapper == nil {
+			continue
+		}
+		if mapper.stopped || mapper.strategy == nil || !mapper.strategy.IsActive() {
+			stats.Error++
+			continue
+		}
+		stats.Sleep++
+	}
+	stats.Total = stats.Active + stats.Sleep + stats.Error
 	return stats
 }
 
-func (s *SimpleSplitter) newMapperLocked() *SimpleMapper {
-	id := s.seq
-	s.seq++
-	mapper := &SimpleMapper{
-		id:      id,
-		events:  s.events,
-		pending: make(map[int64]*proxy.SubmitEvent),
+// Disconnect closes every active or idle upstream connection and clears the mapper tables.
+func (s *SimpleSplitter) Disconnect() {
+	if s == nil {
+		return
 	}
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	for _, mapper := range s.active {
+		if mapper != nil && mapper.strategy != nil {
+			mapper.strategy.Disconnect()
+		}
+	}
+	for _, mapper := range s.idle {
+		if mapper != nil && mapper.strategy != nil {
+			mapper.strategy.Disconnect()
+		}
+	}
+	s.active = make(map[int64]*SimpleMapper)
+	s.idle = make(map[int64]*SimpleMapper)
+}
+
+// ReloadPools reconnects each active or idle mapper using the updated pool list.
+//
+//	s.ReloadPools()
+func (s *SimpleSplitter) ReloadPools() {
+	if s == nil {
+		return
+	}
+	strategies := make([]pool.Strategy, 0, len(s.active)+len(s.idle))
+	s.mu.Lock()
+	for _, mapper := range s.active {
+		if mapper == nil || mapper.strategy == nil {
+			continue
+		}
+		strategies = append(strategies, mapper.strategy)
+	}
+	for _, mapper := range s.idle {
+		if mapper == nil || mapper.strategy == nil {
+			continue
+		}
+		strategies = append(strategies, mapper.strategy)
+	}
+	s.mu.Unlock()
+	for _, strategy := range strategies {
+		if reloadable, ok := strategy.(pool.ReloadableStrategy); ok {
+			reloadable.ReloadPools()
+		}
+	}
+}
+
+func (s *SimpleSplitter) newMapperLocked() *SimpleMapper {
+	id := s.nextMapperID
+	s.nextMapperID++
+	mapper := NewSimpleMapper(id, nil)
+	mapper.events = s.events
 	mapper.strategy = s.factory(mapper)
 	if mapper.strategy == nil {
 		mapper.strategy = s.factory(mapper)
@@ -165,6 +257,18 @@ func (s *SimpleSplitter) newMapperLocked() *SimpleMapper {
 	return mapper
 }
 
+func (s *SimpleSplitter) activeMapperByRouteIDLocked(routeID int64) *SimpleMapper {
+	if s == nil || routeID < 0 {
+		return nil
+	}
+	for _, mapper := range s.active {
+		if mapper != nil && mapper.id == routeID {
+			return mapper
+		}
+	}
+	return nil
+}
+
 // Submit forwards a share to the pool.
 func (m *SimpleMapper) Submit(event *proxy.SubmitEvent) {
 	if m == nil || event == nil || m.strategy == nil {
@@ -172,8 +276,36 @@ func (m *SimpleMapper) Submit(event *proxy.SubmitEvent) {
 	}
 	m.mu.Lock()
 	defer m.mu.Unlock()
-	seq := m.strategy.Submit(event.JobID, event.Nonce, event.Result, event.Algo)
-	m.pending[seq] = event
+	jobID := event.JobID
+	if jobID == "" {
+		jobID = m.currentJob.JobID
+	}
+	if jobID == "" || (jobID != m.currentJob.JobID && jobID != m.prevJob.JobID) {
+		m.rejectInvalidJobLocked(event, m.currentJob)
+		return
+	}
+	submissionJob := m.currentJob
+	if jobID == m.prevJob.JobID && m.prevJob.JobID != "" {
+		submissionJob = m.prevJob
+	}
+	seq := m.strategy.Submit(jobID, event.Nonce, event.Result, event.Algo)
+	m.pending[seq] = submitContext{
+		RequestID: event.RequestID,
+		Diff:      proxy.EffectiveShareDifficulty(submissionJob, event.Miner),
+		StartedAt: time.Now(),
+		JobID:     jobID,
+	}
+}
+
+func (m *SimpleMapper) rejectInvalidJobLocked(event *proxy.SubmitEvent, job proxy.Job) {
+	if event == nil || event.Miner == nil {
+		return
+	}
+	event.Miner.ReplyWithError(event.RequestID, "Invalid job id")
+	if m.events != nil {
+		jobCopy := job
+		m.events.Dispatch(proxy.Event{Type: proxy.EventReject, Miner: event.Miner, Job: &jobCopy, Error: "Invalid job id"})
+	}
 }
 
 // OnJob forwards the latest pool job to the active miner.
@@ -182,6 +314,13 @@ func (m *SimpleMapper) OnJob(job proxy.Job) {
 		return
 	}
 	m.mu.Lock()
+	m.prevJob = m.currentJob
+	if m.prevJob.ClientID != job.ClientID {
+		m.prevJob = proxy.Job{}
+	}
+	m.currentJob = job
+	m.stopped = false
+	m.idleAt = time.Time{}
 	miner := m.miner
 	m.mu.Unlock()
 	if miner == nil {
@@ -196,25 +335,42 @@ func (m *SimpleMapper) OnResultAccepted(sequence int64, accepted bool, errorMess
 		return
 	}
 	m.mu.Lock()
-	ctx := m.pending[sequence]
-	delete(m.pending, sequence)
+	ctx, ok := m.pending[sequence]
+	if ok {
+		delete(m.pending, sequence)
+	}
 	miner := m.miner
+	currentJob := m.currentJob
+	prevJob := m.prevJob
 	m.mu.Unlock()
-	if ctx == nil || miner == nil {
+	if !ok || miner == nil {
 		return
 	}
+	latency := uint16(0)
+	if !ctx.StartedAt.IsZero() {
+		elapsed := time.Since(ctx.StartedAt).Milliseconds()
+		if elapsed > int64(^uint16(0)) {
+			latency = ^uint16(0)
+		} else {
+			latency = uint16(elapsed)
+		}
+	}
+	job := currentJob
+	expired := false
+	if ctx.JobID != "" && ctx.JobID == prevJob.JobID && ctx.JobID != currentJob.JobID {
+		job = prevJob
+		expired = true
+	}
 	if accepted {
 		miner.Success(ctx.RequestID, "OK")
 		if m.events != nil {
-			job := miner.CurrentJob()
-			m.events.Dispatch(proxy.Event{Type: proxy.EventAccept, Miner: miner, Diff: job.DifficultyFromTarget(), Job: &job})
+			m.events.Dispatch(proxy.Event{Type: proxy.EventAccept, Miner: miner, Diff: ctx.Diff, Job: &job, Latency: latency, Expired: expired})
 		}
 		return
 	}
 	miner.ReplyWithError(ctx.RequestID, errorMessage)
 	if m.events != nil {
-		job := miner.CurrentJob()
-		m.events.Dispatch(proxy.Event{Type: proxy.EventReject, Miner: miner, Diff: job.DifficultyFromTarget(), Job: &job, Error: errorMessage})
+		m.events.Dispatch(proxy.Event{Type: proxy.EventReject, Miner: miner, Diff: ctx.Diff, Job: &job, Error: errorMessage, Latency: latency})
 	}
 }
 

splitter/simple/impl_test.go

@@ -0,0 +1,377 @@
+package simple
+
+import (
+	"bufio"
+	"encoding/json"
+	"io"
+	"net"
+	"sync"
+	"testing"
+	"time"
+
+	"dappco.re/go/proxy"
+	"dappco.re/go/proxy/pool"
+)
+
+type activeStrategy struct{}
+
+func (a activeStrategy) Connect()                                    {}
+func (a activeStrategy) Submit(string, string, string, string) int64 { return 0 }
+func (a activeStrategy) Disconnect()                                 {}
+func (a activeStrategy) IsActive() bool                              { return true }
+
+type submitRecordingStrategy struct {
+	submits int
+}
+
+func (s *submitRecordingStrategy) Connect() {}
+
+func (s *submitRecordingStrategy) Submit(string, string, string, string) int64 {
+	s.submits++
+	return int64(s.submits)
+}
+
+func (s *submitRecordingStrategy) Disconnect() {}
+
+func (s *submitRecordingStrategy) IsActive() bool { return true }
+
+func TestSimpleMapper_New_Good(t *testing.T) {
+	strategy := activeStrategy{}
+	mapper := NewSimpleMapper(7, strategy)
+
+	if mapper == nil {
+		t.Fatal("expected mapper")
+	}
+	if mapper.id != 7 {
+		t.Fatalf("expected mapper id 7, got %d", mapper.id)
+	}
+	if mapper.strategy != strategy {
+		t.Fatalf("expected strategy to be stored")
+	}
+	if mapper.pending == nil {
+		t.Fatal("expected pending map to be initialised")
+	}
+}
+
+func TestSimpleSplitter_OnLogin_Good(t *testing.T) {
+	splitter := NewSimpleSplitter(&proxy.Config{ReuseTimeout: 30}, nil, func(listener pool.StratumListener) pool.Strategy {
+		return activeStrategy{}
+	})
+	miner := &proxy.Miner{}
+	job := proxy.Job{JobID: "job-1", Blob: "blob"}
+	mapper := &SimpleMapper{
+		id:         7,
+		strategy:   activeStrategy{},
+		currentJob: job,
+		idleAt:     time.Now(),
+	}
+	splitter.idle[mapper.id] = mapper
+
+	splitter.OnLogin(&proxy.LoginEvent{Miner: miner})
+
+	if miner.RouteID() != mapper.id {
+		t.Fatalf("expected reclaimed mapper route id %d, got %d", mapper.id, miner.RouteID())
+	}
+	if got := miner.CurrentJob().JobID; got != job.JobID {
+		t.Fatalf("expected current job to be restored on reuse, got %q", got)
+	}
+}
+
+func TestSimpleSplitter_OnLogin_Ugly(t *testing.T) {
+	splitter := NewSimpleSplitter(&proxy.Config{ReuseTimeout: 30}, nil, func(listener pool.StratumListener) pool.Strategy {
+		return activeStrategy{}
+	})
+	miner := &proxy.Miner{}
+	expired := &SimpleMapper{
+		id:       7,
+		strategy: activeStrategy{},
+		idleAt:   time.Now().Add(-time.Minute),
+	}
+	splitter.idle[expired.id] = expired
+
+	splitter.OnLogin(&proxy.LoginEvent{Miner: miner})
+
+	if miner.RouteID() == expired.id {
+		t.Fatalf("expected expired mapper not to be reclaimed")
+	}
+	if miner.RouteID() != 0 {
+		t.Fatalf("expected a new mapper to be allocated, got route id %d", miner.RouteID())
+	}
+	if len(splitter.active) != 1 {
+		t.Fatalf("expected one active mapper, got %d", len(splitter.active))
+	}
+	if len(splitter.idle) != 1 {
+		t.Fatalf("expected expired mapper to remain idle until GC, got %d idle mappers", len(splitter.idle))
+	}
+}
+
+func TestSimpleSplitter_OnSubmit_UsesRouteID_Good(t *testing.T) {
+	strategy := &submitRecordingStrategy{}
+	splitter := NewSimpleSplitter(&proxy.Config{ReuseTimeout: 30}, nil, nil)
+	miner := proxy.NewMiner(discardConn{}, 3333, nil)
+	miner.SetID(21)
+	miner.SetRouteID(7)
+
+	mapper := &SimpleMapper{
+		id:         7,
+		miner:      miner,
+		currentJob: proxy.Job{JobID: "job-1", Blob: "blob", Target: "b88d0600"},
+		strategy:   strategy,
+		pending:    make(map[int64]submitContext),
+	}
+	splitter.active[99] = mapper
+
+	splitter.OnSubmit(&proxy.SubmitEvent{
+		Miner:     miner,
+		JobID:     "job-1",
+		Nonce:     "deadbeef",
+		Result:    "hash",
+		RequestID: 11,
+	})
+
+	if strategy.submits != 1 {
+		t.Fatalf("expected one submit routed by route id, got %d", strategy.submits)
+	}
+	if len(mapper.pending) != 1 {
+		t.Fatalf("expected routed submit to create one pending entry, got %d", len(mapper.pending))
+	}
+}
+
+func TestSimpleSplitter_Upstreams_Good(t *testing.T) {
+	splitter := NewSimpleSplitter(&proxy.Config{ReuseTimeout: 30}, nil, func(listener pool.StratumListener) pool.Strategy {
+		return activeStrategy{}
+	})
+	splitter.active[1] = &SimpleMapper{id: 1, strategy: activeStrategy{}}
+	splitter.idle[2] = &SimpleMapper{id: 2, strategy: activeStrategy{}, idleAt: time.Now()}
+
+	stats := splitter.Upstreams()
+
+	if stats.Active != 1 {
+		t.Fatalf("expected one active upstream, got %d", stats.Active)
+	}
+	if stats.Sleep != 1 {
+		t.Fatalf("expected one sleeping upstream, got %d", stats.Sleep)
+	}
+	if stats.Error != 0 {
+		t.Fatalf("expected no error upstreams, got %d", stats.Error)
+	}
+	if stats.Total != 2 {
+		t.Fatalf("expected total upstreams to be 2, got %d", stats.Total)
+	}
+}
+
+func TestSimpleSplitter_Upstreams_Ugly(t *testing.T) {
+	splitter := NewSimpleSplitter(&proxy.Config{ReuseTimeout: 30}, nil, func(listener pool.StratumListener) pool.Strategy {
+		return activeStrategy{}
+	})
+	splitter.active[1] = &SimpleMapper{id: 1, strategy: activeStrategy{}, stopped: true}
+	splitter.idle[2] = &SimpleMapper{id: 2, strategy: activeStrategy{}, stopped: true, idleAt: time.Now()}
+
+	stats := splitter.Upstreams()
+
+	if stats.Active != 0 {
+		t.Fatalf("expected no active upstreams, got %d", stats.Active)
+	}
+	if stats.Sleep != 0 {
+		t.Fatalf("expected no sleeping upstreams, got %d", stats.Sleep)
+	}
+	if stats.Error != 2 {
+		t.Fatalf("expected both upstreams to be counted as error, got %d", stats.Error)
+	}
+	if stats.Total != 2 {
+		t.Fatalf("expected total upstreams to be 2, got %d", stats.Total)
+	}
+}
+
+func TestSimpleSplitter_Upstreams_RecoveryResetsStopped_Good(t *testing.T) {
+	splitter := NewSimpleSplitter(&proxy.Config{ReuseTimeout: 30}, nil, func(listener pool.StratumListener) pool.Strategy {
+		return activeStrategy{}
+	})
+	mapper := &SimpleMapper{id: 1, strategy: activeStrategy{}, stopped: true}
+	splitter.active[1] = mapper
+
+	before := splitter.Upstreams()
+	if before.Error != 1 {
+		t.Fatalf("expected disconnected mapper to count as error, got %+v", before)
+	}
+
+	mapper.OnJob(proxy.Job{JobID: "job-1", Blob: "blob"})
+
+	after := splitter.Upstreams()
+	if after.Active != 1 {
+		t.Fatalf("expected recovered mapper to count as active, got %+v", after)
+	}
+	if after.Error != 0 {
+		t.Fatalf("expected recovered mapper not to remain in error, got %+v", after)
+	}
+}
+
+type discardConn struct{}
+
+func (discardConn) Read([]byte) (int, error)         { return 0, io.EOF }
+func (discardConn) Write(p []byte) (int, error)      { return len(p), nil }
+func (discardConn) Close() error                     { return nil }
+func (discardConn) LocalAddr() net.Addr              { return nil }
+func (discardConn) RemoteAddr() net.Addr             { return nil }
+func (discardConn) SetDeadline(time.Time) error      { return nil }
+func (discardConn) SetReadDeadline(time.Time) error  { return nil }
+func (discardConn) SetWriteDeadline(time.Time) error { return nil }
+
+func TestSimpleMapper_OnResultAccepted_Expired(t *testing.T) {
+	bus := proxy.NewEventBus()
+	events := make(chan proxy.Event, 1)
+	var once sync.Once
+	bus.Subscribe(proxy.EventAccept, func(e proxy.Event) {
+		once.Do(func() {
+			events <- e
+		})
+	})
+
+	miner := proxy.NewMiner(discardConn{}, 3333, nil)
+	miner.SetID(1)
+	mapper := &SimpleMapper{
+		miner:      miner,
+		currentJob: proxy.Job{JobID: "job-new", Blob: "blob-new", Target: "b88d0600"},
+		prevJob:    proxy.Job{JobID: "job-old", Blob: "blob-old", Target: "b88d0600"},
+		events:     bus,
+		pending: map[int64]submitContext{
+			7: {RequestID: 9, StartedAt: time.Now(), JobID: "job-old"},
+		},
+	}
+
+	mapper.OnResultAccepted(7, true, "")
+
+	select {
+	case event := <-events:
+		if !event.Expired {
+			t.Fatalf("expected expired share to be flagged")
+		}
+		if event.Job == nil || event.Job.JobID != "job-old" {
+			t.Fatalf("expected previous job to be attached, got %+v", event.Job)
+		}
+	case <-time.After(time.Second):
+		t.Fatal("expected accept event")
+	}
+}
+
+func TestSimpleMapper_OnResultAccepted_CustomDiffUsesEffectiveDifficulty(t *testing.T) {
+	bus := proxy.NewEventBus()
+	events := make(chan proxy.Event, 1)
+	var once sync.Once
+	bus.Subscribe(proxy.EventAccept, func(e proxy.Event) {
+		once.Do(func() {
+			events <- e
+		})
+	})
+
+	miner := proxy.NewMiner(discardConn{}, 3333, nil)
+	miner.SetID(2)
+	job := proxy.Job{JobID: "job-new", Blob: "blob-new", Target: "b88d0600"}
+	mapper := &SimpleMapper{
+		miner:      miner,
+		currentJob: job,
+		events:     bus,
+		pending: map[int64]submitContext{
+			8: {
+				RequestID: 10,
+				Diff:      25000,
+				StartedAt: time.Now(),
+				JobID:     "job-new",
+			},
+		},
+	}
+
+	mapper.OnResultAccepted(8, true, "")
+
+	select {
+	case event := <-events:
+		if event.Diff != 25000 {
+			t.Fatalf("expected effective difficulty 25000, got %d", event.Diff)
+		}
+	case <-time.After(time.Second):
+		t.Fatal("expected accept event")
+	}
+}
+
+func TestSimpleMapper_OnJob_PreservesPreviousJobForSamePoolSession_Good(t *testing.T) {
+	mapper := &SimpleMapper{
+		currentJob: proxy.Job{JobID: "job-1", Blob: "blob-1", ClientID: "session-a"},
+	}
+
+	mapper.OnJob(proxy.Job{JobID: "job-2", Blob: "blob-2", ClientID: "session-a"})
+
+	if mapper.currentJob.JobID != "job-2" {
+		t.Fatalf("expected current job to roll forward, got %q", mapper.currentJob.JobID)
+	}
+	if mapper.prevJob.JobID != "job-1" {
+		t.Fatalf("expected previous job to remain available within one pool session, got %q", mapper.prevJob.JobID)
+	}
+}
+
+func TestSimpleMapper_OnJob_ResetsPreviousJobAcrossPoolSessions_Ugly(t *testing.T) {
+	mapper := &SimpleMapper{
+		currentJob: proxy.Job{JobID: "job-1", Blob: "blob-1", ClientID: "session-a"},
+		prevJob:    proxy.Job{JobID: "job-0", Blob: "blob-0", ClientID: "session-a"},
+	}
+
+	mapper.OnJob(proxy.Job{JobID: "job-2", Blob: "blob-2", ClientID: "session-b"})
+
+	if mapper.currentJob.JobID != "job-2" {
+		t.Fatalf("expected current job to advance after session change, got %q", mapper.currentJob.JobID)
+	}
+	if mapper.prevJob.JobID != "" {
+		t.Fatalf("expected previous job history to reset on new pool session, got %q", mapper.prevJob.JobID)
+	}
+}
+
+func TestSimpleMapper_Submit_InvalidJob_Good(t *testing.T) {
+	minerConn, clientConn := net.Pipe()
+	defer minerConn.Close()
+	defer clientConn.Close()
+
+	miner := proxy.NewMiner(minerConn, 3333, nil)
+	mapper := &SimpleMapper{
+		miner:      miner,
+		currentJob: proxy.Job{JobID: "job-1", Blob: "blob", Target: "b88d0600"},
+		prevJob:    proxy.Job{JobID: "job-0", Blob: "blob", Target: "b88d0600"},
+		strategy:   activeStrategy{},
+		pending:    make(map[int64]submitContext),
+	}
+
+	done := make(chan struct{})
+	go func() {
+		mapper.Submit(&proxy.SubmitEvent{
+			Miner:     miner,
+			JobID:     "job-missing",
+			Nonce:     "deadbeef",
+			Result:    "hash",
+			RequestID: 9,
+		})
+		close(done)
+	}()
+
+	line, err := bufio.NewReader(clientConn).ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read error reply: %v", err)
+	}
+	<-done
+
+	var payload struct {
+		ID    float64 `json:"id"`
+		Error struct {
+			Message string `json:"message"`
+		} `json:"error"`
+	}
+	if err := json.Unmarshal(line, &payload); err != nil {
+		t.Fatalf("unmarshal error reply: %v", err)
+	}
+	if payload.ID != 9 {
+		t.Fatalf("expected request id 9, got %v", payload.ID)
+	}
+	if payload.Error.Message != "Invalid job id" {
+		t.Fatalf("expected invalid job error, got %q", payload.Error.Message)
+	}
+	if len(mapper.pending) != 0 {
+		t.Fatalf("expected invalid submit not to create a pending entry")
+	}
+}

splitter/simple/mapper.go

@@ -14,12 +14,32 @@ import (
 //
 //	m := simple.NewSimpleMapper(id, strategy)
 type SimpleMapper struct {
-	id       int64
-	miner    *proxy.Miner // nil when idle
-	strategy pool.Strategy
-	idleAt   time.Time // zero when active
-	stopped  bool
-	events   *proxy.EventBus
-	pending  map[int64]*proxy.SubmitEvent
-	mu       sync.Mutex
+	id         int64
+	miner      *proxy.Miner // nil when idle
+	currentJob proxy.Job
+	prevJob    proxy.Job
+	strategy   pool.Strategy
+	idleAt     time.Time // zero when active
+	stopped    bool
+	events     *proxy.EventBus
+	pending    map[int64]submitContext
+	mu         sync.Mutex
+}
+
+type submitContext struct {
+	RequestID int64
+	Diff      uint64
+	StartedAt time.Time
+	JobID     string
+}
+
+// NewSimpleMapper creates a passthrough mapper for one pool connection.
+//
+//	m := simple.NewSimpleMapper(7, strategy)
+func NewSimpleMapper(id int64, strategy pool.Strategy) *SimpleMapper {
+	return &SimpleMapper{
+		id:       id,
+		strategy: strategy,
+		pending:  make(map[int64]submitContext),
+	}
 }

splitter/simple/reload_test.go

@@ -0,0 +1,68 @@
+package simple
+
+import (
+	"testing"
+
+	"dappco.re/go/proxy/pool"
+)
+
+type reloadableStrategy struct {
+	reloads int
+}
+
+func (s *reloadableStrategy) Connect()                                       {}
+func (s *reloadableStrategy) Submit(jobID, nonce, result, algo string) int64 { return 0 }
+func (s *reloadableStrategy) Disconnect()                                    {}
+func (s *reloadableStrategy) IsActive() bool                                 { return true }
+func (s *reloadableStrategy) ReloadPools()                                   { s.reloads++ }
+
+var _ pool.ReloadableStrategy = (*reloadableStrategy)(nil)
+
+func TestSimpleSplitter_ReloadPools_Good(t *testing.T) {
+	strategy := &reloadableStrategy{}
+	splitter := &SimpleSplitter{
+		active: map[int64]*SimpleMapper{
+			1: {strategy: strategy},
+		},
+		idle: map[int64]*SimpleMapper{},
+	}
+
+	splitter.ReloadPools()
+
+	if strategy.reloads != 1 {
+		t.Fatalf("expected active mapper strategy to reload once, got %d", strategy.reloads)
+	}
+}
+
+func TestSimpleSplitter_ReloadPools_Bad(t *testing.T) {
+	splitter := &SimpleSplitter{
+		active: map[int64]*SimpleMapper{
+			1: {strategy: nil},
+		},
+		idle: map[int64]*SimpleMapper{},
+	}
+
+	splitter.ReloadPools()
+}
+
+func TestSimpleSplitter_ReloadPools_Ugly(t *testing.T) {
+	active := &reloadableStrategy{}
+	idle := &reloadableStrategy{}
+	splitter := &SimpleSplitter{
+		active: map[int64]*SimpleMapper{
+			1: {strategy: active},
+		},
+		idle: map[int64]*SimpleMapper{
+			2: {strategy: idle},
+		},
+	}
+
+	splitter.ReloadPools()
+
+	if active.reloads != 1 {
+		t.Fatalf("expected active mapper reload, got %d", active.reloads)
+	}
+	if idle.reloads != 1 {
+		t.Fatalf("expected idle mapper reload, got %d", idle.reloads)
+	}
+}

splitter/simple/splitter.go

@@ -18,11 +18,11 @@ import (
 //
 //	s := simple.NewSimpleSplitter(cfg, eventBus, strategyFactory)
 type SimpleSplitter struct {
-	active  map[int64]*SimpleMapper // minerID → mapper
-	idle    map[int64]*SimpleMapper // mapperID → mapper (reuse pool, keyed by mapper seq)
-	cfg     *proxy.Config
-	events  *proxy.EventBus
-	factory pool.StrategyFactory
-	mu      sync.Mutex
-	seq     int64 // monotonic mapper sequence counter
+	active       map[int64]*SimpleMapper // minerID → mapper
+	idle         map[int64]*SimpleMapper // mapperID → mapper (reuse pool, keyed by mapper ID)
+	config       *proxy.Config
+	events       *proxy.EventBus
+	factory      pool.StrategyFactory
+	mu           sync.Mutex
+	nextMapperID int64 // monotonic mapper ID counter
 }

state_stop_test.go

@@ -0,0 +1,137 @@
+package proxy
+
+import (
+	"net"
+	"testing"
+	"time"
+)
+
+func TestProxy_Stop_Good(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+
+	miner := NewMiner(clientConn, 3333, nil)
+	splitter := &stubSplitter{}
+	proxyInstance := &Proxy{
+		done:     make(chan struct{}),
+		miners:   map[int64]*Miner{miner.ID(): miner},
+		splitter: splitter,
+	}
+
+	done := make(chan error, 1)
+	go func() {
+		buf := make([]byte, 1)
+		_, err := serverConn.Read(buf)
+		done <- err
+	}()
+
+	time.Sleep(10 * time.Millisecond)
+	proxyInstance.Stop()
+
+	select {
+	case err := <-done:
+		if err == nil {
+			t.Fatalf("expected miner connection to close during Stop")
+		}
+	case <-time.After(time.Second):
+		t.Fatalf("expected miner connection to close during Stop")
+	}
+	if !splitter.disconnected {
+		t.Fatalf("expected splitter to be disconnected during Stop")
+	}
+}
+
+func TestProxy_Stop_Bad(t *testing.T) {
+	var proxyInstance *Proxy
+
+	proxyInstance.Stop()
+}
+
+func TestProxy_Stop_Ugly(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+
+	miner := NewMiner(clientConn, 3333, nil)
+	proxyInstance := &Proxy{
+		done:   make(chan struct{}),
+		miners: map[int64]*Miner{miner.ID(): miner},
+	}
+
+	proxyInstance.Stop()
+	proxyInstance.Stop()
+
+	buf := make([]byte, 1)
+	if _, err := serverConn.Read(buf); err == nil {
+		t.Fatalf("expected closed connection after repeated Stop calls")
+	}
+}
+
+func TestProxy_Stop_WaitsBeforeDisconnectingSubmitPaths(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+
+	miner := NewMiner(clientConn, 3333, nil)
+	splitter := &blockingStopSplitter{disconnectedCh: make(chan struct{})}
+	proxyInstance := &Proxy{
+		done:     make(chan struct{}),
+		miners:   map[int64]*Miner{miner.ID(): miner},
+		splitter: splitter,
+	}
+	proxyInstance.submitCount.Store(1)
+
+	stopped := make(chan struct{})
+	go func() {
+		proxyInstance.Stop()
+		close(stopped)
+	}()
+
+	select {
+	case <-splitter.disconnectedCh:
+		t.Fatalf("expected splitter disconnect to wait for submit drain")
+	case <-stopped:
+		t.Fatalf("expected Stop to keep waiting while submits are in flight")
+	case <-time.After(50 * time.Millisecond):
+	}
+
+	proxyInstance.submitCount.Store(0)
+
+	select {
+	case <-splitter.disconnectedCh:
+	case <-time.After(time.Second):
+		t.Fatalf("expected splitter disconnect after submit drain")
+	}
+
+	select {
+	case <-stopped:
+	case <-time.After(time.Second):
+		t.Fatalf("expected Stop to finish after submit drain")
+	}
+}
+
+type stubSplitter struct {
+	disconnected bool
+}
+
+func (s *stubSplitter) Connect()                    {}
+func (s *stubSplitter) OnLogin(event *LoginEvent)   {}
+func (s *stubSplitter) OnSubmit(event *SubmitEvent) {}
+func (s *stubSplitter) OnClose(event *CloseEvent)   {}
+func (s *stubSplitter) Tick(ticks uint64)           {}
+func (s *stubSplitter) GC()                         {}
+func (s *stubSplitter) Upstreams() UpstreamStats    { return UpstreamStats{} }
+func (s *stubSplitter) Disconnect()                 { s.disconnected = true }
+
+type blockingStopSplitter struct {
+	disconnectedCh chan struct{}
+}
+
+func (s *blockingStopSplitter) Connect()                    {}
+func (s *blockingStopSplitter) OnLogin(event *LoginEvent)   {}
+func (s *blockingStopSplitter) OnSubmit(event *SubmitEvent) {}
+func (s *blockingStopSplitter) OnClose(event *CloseEvent)   {}
+func (s *blockingStopSplitter) Tick(ticks uint64)           {}
+func (s *blockingStopSplitter) GC()                         {}
+func (s *blockingStopSplitter) Upstreams() UpstreamStats    { return UpstreamStats{} }
+func (s *blockingStopSplitter) Disconnect() {
+	close(s.disconnectedCh)
+}

state_submit_test.go

@@ -0,0 +1,33 @@
+package proxy
+
+import (
+	"testing"
+	"time"
+)
+
+func TestProxy_Stop_WaitsForSubmitDrain(t *testing.T) {
+	p := &Proxy{
+		done: make(chan struct{}),
+	}
+	p.submitCount.Store(1)
+
+	stopped := make(chan struct{})
+	go func() {
+		p.Stop()
+		close(stopped)
+	}()
+
+	select {
+	case <-stopped:
+		t.Fatalf("expected Stop to wait for pending submits")
+	case <-time.After(50 * time.Millisecond):
+	}
+
+	p.submitCount.Store(0)
+
+	select {
+	case <-stopped:
+	case <-time.After(time.Second):
+		t.Fatalf("expected Stop to finish after pending submits drain")
+	}
+}

stats.go

@@ -9,9 +9,11 @@ import (
 // Stats tracks global proxy metrics. Hot-path counters are atomic. Hashrate windows
 // use a ring buffer per window size, advanced by Tick().
 //
-//	s := proxy.NewStats()
-//	bus.Subscribe(proxy.EventAccept, s.OnAccept)
-//	bus.Subscribe(proxy.EventReject, s.OnReject)
+//	stats := proxy.NewStats()
+//	bus.Subscribe(proxy.EventAccept, stats.OnAccept)
+//	bus.Subscribe(proxy.EventReject, stats.OnReject)
+//	stats.Tick()
+//	summary := stats.Summary()
 type Stats struct {
 	accepted    atomic.Uint64
 	rejected    atomic.Uint64
@@ -28,7 +30,6 @@ type Stats struct {
 	mu          sync.Mutex
 }
 
-// Hashrate window sizes in seconds. Index maps to Stats.windows and SummaryResponse.Hashrate.
 const (
 	HashrateWindow60s   = 0 // 1 minute
 	HashrateWindow600s  = 1 // 10 minutes
@@ -38,7 +39,9 @@ const (
 	HashrateWindowAll   = 5 // all-time (single accumulator, no window)
 )
 
-// tickWindow is a fixed-capacity ring buffer of per-second difficulty sums.
+// tickWindow is a fixed-capacity ring buffer of per-second difficulty totals.
+//
+// window := newTickWindow(60)
 type tickWindow struct {
 	buckets []uint64
 	pos     int
@@ -47,15 +50,17 @@ type tickWindow struct {
 
 // StatsSummary is the serialisable snapshot returned by Summary().
 //
-//	summary := stats.Summary()
+//	summary := proxy.NewStats().Summary()
+//	_ = summary.Hashrate[0] // 60-second window H/s
 type StatsSummary struct {
-	Accepted   uint64     `json:"accepted"`
-	Rejected   uint64     `json:"rejected"`
-	Invalid    uint64     `json:"invalid"`
-	Expired    uint64     `json:"expired"`
-	Hashes     uint64     `json:"hashes_total"`
-	AvgTime    uint32     `json:"avg_time"` // seconds per accepted share
-	AvgLatency uint32     `json:"latency"`  // median pool response latency in ms
-	Hashrate   [6]float64 `json:"hashrate"` // H/s per window (index = HashrateWindow* constants)
-	TopDiff    [10]uint64 `json:"best"`
+	Accepted        uint64                           `json:"accepted"`
+	Rejected        uint64                           `json:"rejected"`
+	Invalid         uint64                           `json:"invalid"`
+	Expired         uint64                           `json:"expired"`
+	Hashes          uint64                           `json:"hashes_total"`
+	AvgTime         uint32                           `json:"avg_time"` // seconds per accepted share
+	AvgLatency      uint32                           `json:"latency"`  // median pool response latency in ms
+	Hashrate        [6]float64                       `json:"hashrate"` // H/s per window (index = HashrateWindow* constants)
+	TopDiff         [10]uint64                       `json:"best"`
+	CustomDiffStats map[uint64]CustomDiffBucketStats `json:"custom_diff_stats,omitempty"`
 }

stats_test.go

@@ -0,0 +1,173 @@
+package proxy
+
+import (
+	"sync"
+	"testing"
+)
+
+// TestStats_OnAccept_Good verifies that accepted counter, hashes, and topDiff are updated.
+//
+//	stats := proxy.NewStats()
+//	stats.OnAccept(proxy.Event{Diff: 100000, Latency: 82})
+//	summary := stats.Summary()
+//	_ = summary.Accepted  // 1
+//	_ = summary.Hashes    // 100000
+func TestStats_OnAccept_Good(t *testing.T) {
+	stats := NewStats()
+
+	stats.OnAccept(Event{Diff: 100000, Latency: 82})
+
+	summary := stats.Summary()
+	if summary.Accepted != 1 {
+		t.Fatalf("expected accepted 1, got %d", summary.Accepted)
+	}
+	if summary.Hashes != 100000 {
+		t.Fatalf("expected hashes 100000, got %d", summary.Hashes)
+	}
+	if summary.TopDiff[0] != 100000 {
+		t.Fatalf("expected top diff 100000, got %d", summary.TopDiff[0])
+	}
+}
+
+// TestStats_OnAccept_Bad verifies concurrent OnAccept calls do not race.
+//
+//	stats := proxy.NewStats()
+//	// 100 goroutines each call OnAccept — no data race under -race flag.
+func TestStats_OnAccept_Bad(t *testing.T) {
+	stats := NewStats()
+	var wg sync.WaitGroup
+	for i := 0; i < 100; i++ {
+		wg.Add(1)
+		go func(diff uint64) {
+			defer wg.Done()
+			stats.OnAccept(Event{Diff: diff, Latency: 10})
+		}(uint64(i + 1))
+	}
+	wg.Wait()
+
+	summary := stats.Summary()
+	if summary.Accepted != 100 {
+		t.Fatalf("expected 100 accepted, got %d", summary.Accepted)
+	}
+}
+
+// TestStats_OnAccept_Ugly verifies that 15 accepts with varying diffs fill all topDiff slots.
+//
+//	stats := proxy.NewStats()
+//	// 15 accepts with diffs 1..15 → topDiff[9] is 6 (10th highest), not 0
+func TestStats_OnAccept_Ugly(t *testing.T) {
+	stats := NewStats()
+
+	for i := 1; i <= 15; i++ {
+		stats.OnAccept(Event{Diff: uint64(i)})
+	}
+
+	summary := stats.Summary()
+	// top 10 should be 15, 14, 13, ..., 6
+	if summary.TopDiff[0] != 15 {
+		t.Fatalf("expected top diff[0]=15, got %d", summary.TopDiff[0])
+	}
+	if summary.TopDiff[9] != 6 {
+		t.Fatalf("expected top diff[9]=6, got %d", summary.TopDiff[9])
+	}
+}
+
+// TestStats_OnReject_Good verifies that rejected and invalid counters are updated.
+//
+//	stats := proxy.NewStats()
+//	stats.OnReject(proxy.Event{Error: "Low difficulty share"})
+func TestStats_OnReject_Good(t *testing.T) {
+	stats := NewStats()
+
+	stats.OnReject(Event{Error: "Low difficulty share"})
+	stats.OnReject(Event{Error: "Malformed share"})
+
+	summary := stats.Summary()
+	if summary.Rejected != 2 {
+		t.Fatalf("expected two rejected shares, got %d", summary.Rejected)
+	}
+	if summary.Invalid != 2 {
+		t.Fatalf("expected two invalid shares, got %d", summary.Invalid)
+	}
+}
+
+// TestStats_OnReject_Bad verifies that a non-invalid rejection increments rejected but not invalid.
+//
+//	stats := proxy.NewStats()
+//	stats.OnReject(proxy.Event{Error: "Stale share"})
+func TestStats_OnReject_Bad(t *testing.T) {
+	stats := NewStats()
+
+	stats.OnReject(Event{Error: "Stale share"})
+
+	summary := stats.Summary()
+	if summary.Rejected != 1 {
+		t.Fatalf("expected one rejected, got %d", summary.Rejected)
+	}
+	if summary.Invalid != 0 {
+		t.Fatalf("expected zero invalid for non-invalid reason, got %d", summary.Invalid)
+	}
+}
+
+// TestStats_OnReject_Ugly verifies an expired accepted share increments both accepted and expired.
+//
+//	stats := proxy.NewStats()
+//	stats.OnAccept(proxy.Event{Diff: 1000, Expired: true})
+func TestStats_OnReject_Ugly(t *testing.T) {
+	stats := NewStats()
+
+	stats.OnAccept(Event{Diff: 1000, Expired: true})
+
+	summary := stats.Summary()
+	if summary.Accepted != 1 {
+		t.Fatalf("expected accepted 1, got %d", summary.Accepted)
+	}
+	if summary.Expired != 1 {
+		t.Fatalf("expected expired 1, got %d", summary.Expired)
+	}
+}
+
+// TestStats_Tick_Good verifies that Tick advances the rolling window position.
+//
+//	stats := proxy.NewStats()
+//	stats.OnAccept(proxy.Event{Diff: 500})
+//	stats.Tick()
+//	summary := stats.Summary()
+func TestStats_Tick_Good(t *testing.T) {
+	stats := NewStats()
+
+	stats.OnAccept(Event{Diff: 500})
+	stats.Tick()
+
+	summary := stats.Summary()
+	// After one tick, the hashrate should still include the 500 diff
+	if summary.Hashrate[HashrateWindow60s] == 0 {
+		t.Fatalf("expected non-zero 60s hashrate after accept and tick")
+	}
+}
+
+// TestStats_OnLogin_OnClose_Good verifies miner count tracking.
+//
+//	stats := proxy.NewStats()
+//	stats.OnLogin(proxy.Event{Miner: &proxy.Miner{}})
+//	stats.OnClose(proxy.Event{Miner: &proxy.Miner{}})
+func TestStats_OnLogin_OnClose_Good(t *testing.T) {
+	stats := NewStats()
+	m := &Miner{}
+
+	stats.OnLogin(Event{Miner: m})
+	if got := stats.miners.Load(); got != 1 {
+		t.Fatalf("expected 1 miner, got %d", got)
+	}
+	if got := stats.maxMiners.Load(); got != 1 {
+		t.Fatalf("expected max miners 1, got %d", got)
+	}
+
+	stats.OnClose(Event{Miner: m})
+	if got := stats.miners.Load(); got != 0 {
+		t.Fatalf("expected 0 miners after close, got %d", got)
+	}
+	if got := stats.maxMiners.Load(); got != 1 {
+		t.Fatalf("expected max miners to remain 1, got %d", got)
+	}
+}

tls_test.go

@@ -0,0 +1,36 @@
+package proxy
+
+import (
+	"crypto/tls"
+	"testing"
+)
+
+func TestTLS_applyTLSCiphers_Good(t *testing.T) {
+	cfg := &tls.Config{}
+
+	applyTLSCiphers(cfg, "ECDHE-RSA-AES128-GCM-SHA256, TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256")
+
+	if len(cfg.CipherSuites) != 2 {
+		t.Fatalf("expected two recognised cipher suites, got %d", len(cfg.CipherSuites))
+	}
+}
+
+func TestTLS_applyTLSCiphers_Bad(t *testing.T) {
+	cfg := &tls.Config{}
+
+	applyTLSCiphers(cfg, "made-up-cipher-one:made-up-cipher-two")
+
+	if len(cfg.CipherSuites) != 0 {
+		t.Fatalf("expected unknown cipher names to be ignored, got %#v", cfg.CipherSuites)
+	}
+}
+
+func TestTLS_applyTLSCiphers_Ugly(t *testing.T) {
+	cfg := &tls.Config{}
+
+	applyTLSCiphers(cfg, "  aes128-sha | ECDHE-RSA-AES256-GCM-SHA384 ; tls_ecdhe_ecdsa_with_aes_256_gcm_sha384  ")
+
+	if len(cfg.CipherSuites) != 3 {
+		t.Fatalf("expected mixed separators and casing to be accepted, got %d", len(cfg.CipherSuites))
+	}
+}

worker.go

@@ -8,18 +8,22 @@ import (
 // Workers maintains per-worker aggregate stats. Workers are identified by name,
 // derived from the miner's login fields per WorkersMode.
 //
-//	w := proxy.NewWorkers(proxy.WorkersByRigID, bus)
+//	workers := proxy.NewWorkers(proxy.WorkersByRigID, bus)
+//	workers.OnLogin(proxy.Event{Miner: miner})
+//	records := workers.List()
 type Workers struct {
-	mode      WorkersMode
-	entries   []WorkerRecord // ordered by first-seen (stable)
-	nameIndex map[string]int // workerName → entries index
-	idIndex   map[int64]int  // minerID → entries index
-	mu        sync.RWMutex
+	mode       WorkersMode
+	entries    []WorkerRecord // ordered by first-seen (stable)
+	nameIndex  map[string]int // workerName → entries index
+	idIndex    map[int64]int  // minerID → entries index
+	subscribed bool
+	mu         sync.RWMutex
 }
 
-// WorkerRecord is the per-identity aggregate.
+// WorkerRecord is the per-identity aggregate with rolling hashrate windows.
 //
-//	hr60 := record.Hashrate(60)
+//	record := proxy.WorkerRecord{Name: "rig-alpha", Accepted: 10, Hashes: 500000}
+//	hr60 := record.Hashrate(60) // H/s over the last 60 seconds
 type WorkerRecord struct {
 	Name        string
 	LastIP      string

worker_test.go

@@ -0,0 +1,164 @@
+package proxy
+
+import "testing"
+
+func TestWorker_NewWorkers_Good(t *testing.T) {
+	bus := NewEventBus()
+	workers := NewWorkers(WorkersByRigID, bus)
+	miner := &Miner{id: 7, user: "wallet", rigID: "rig-1", ip: "10.0.0.1"}
+
+	bus.Dispatch(Event{Type: EventLogin, Miner: miner})
+
+	records := workers.List()
+	if len(records) != 1 {
+		t.Fatalf("expected one worker record, got %d", len(records))
+	}
+	if records[0].Name != "rig-1" {
+		t.Fatalf("expected rig id worker name, got %q", records[0].Name)
+	}
+	if records[0].Connections != 1 {
+		t.Fatalf("expected one connection, got %d", records[0].Connections)
+	}
+}
+
+func TestWorker_NewWorkers_Bad(t *testing.T) {
+	workers := NewWorkers(WorkersDisabled, nil)
+	if workers == nil {
+		t.Fatalf("expected workers instance")
+	}
+	if got := workers.List(); len(got) != 0 {
+		t.Fatalf("expected no worker records, got %d", len(got))
+	}
+}
+
+func TestWorker_NewWorkers_Ugly(t *testing.T) {
+	bus := NewEventBus()
+	workers := NewWorkers(WorkersByUser, bus)
+	workers.bindEvents(bus)
+
+	miner := &Miner{id: 11, user: "wallet", ip: "10.0.0.2"}
+	bus.Dispatch(Event{Type: EventLogin, Miner: miner})
+
+	records := workers.List()
+	if len(records) != 1 {
+		t.Fatalf("expected one worker record, got %d", len(records))
+	}
+	if records[0].Connections != 1 {
+		t.Fatalf("expected a single subscription path, got %d connections", records[0].Connections)
+	}
+}
+
+// TestWorker_Hashrate_Good verifies that recording an accepted share produces a nonzero
+// hashrate reading from the 60-second window.
+//
+//	record := proxy.WorkerRecord{}
+//	record.Hashrate(60) // > 0.0 after an accepted share
+func TestWorker_Hashrate_Good(t *testing.T) {
+	bus := NewEventBus()
+	workers := NewWorkers(WorkersByUser, bus)
+
+	miner := &Miner{id: 100, user: "hashtest", ip: "10.0.0.10"}
+	bus.Dispatch(Event{Type: EventLogin, Miner: miner})
+	bus.Dispatch(Event{Type: EventAccept, Miner: miner, Diff: 50000})
+
+	records := workers.List()
+	if len(records) != 1 {
+		t.Fatalf("expected one worker record, got %d", len(records))
+	}
+	hr := records[0].Hashrate(60)
+	if hr <= 0 {
+		t.Fatalf("expected nonzero hashrate for 60-second window after accept, got %f", hr)
+	}
+}
+
+// TestWorker_Hashrate_Bad verifies that an invalid window size returns 0.
+//
+//	record := proxy.WorkerRecord{}
+//	record.Hashrate(999) // 0.0 (unsupported window)
+func TestWorker_Hashrate_Bad(t *testing.T) {
+	bus := NewEventBus()
+	workers := NewWorkers(WorkersByUser, bus)
+
+	miner := &Miner{id: 101, user: "hashtest-bad", ip: "10.0.0.11"}
+	bus.Dispatch(Event{Type: EventLogin, Miner: miner})
+	bus.Dispatch(Event{Type: EventAccept, Miner: miner, Diff: 50000})
+
+	records := workers.List()
+	if len(records) != 1 {
+		t.Fatalf("expected one worker record, got %d", len(records))
+	}
+	hr := records[0].Hashrate(999)
+	if hr != 0 {
+		t.Fatalf("expected zero hashrate for unsupported window, got %f", hr)
+	}
+	hrZero := records[0].Hashrate(0)
+	if hrZero != 0 {
+		t.Fatalf("expected zero hashrate for zero window, got %f", hrZero)
+	}
+	hrNeg := records[0].Hashrate(-1)
+	if hrNeg != 0 {
+		t.Fatalf("expected zero hashrate for negative window, got %f", hrNeg)
+	}
+}
+
+// TestWorker_Hashrate_Ugly verifies that calling Hashrate on a nil record returns 0
+// and that a worker with no accepts also returns 0.
+//
+//	var record *proxy.WorkerRecord
+//	record.Hashrate(60) // 0.0
+func TestWorker_Hashrate_Ugly(t *testing.T) {
+	var nilRecord *WorkerRecord
+	if hr := nilRecord.Hashrate(60); hr != 0 {
+		t.Fatalf("expected zero hashrate for nil record, got %f", hr)
+	}
+
+	bus := NewEventBus()
+	workers := NewWorkers(WorkersByUser, bus)
+
+	miner := &Miner{id: 102, user: "hashtest-ugly", ip: "10.0.0.12"}
+	bus.Dispatch(Event{Type: EventLogin, Miner: miner})
+
+	records := workers.List()
+	if len(records) != 1 {
+		t.Fatalf("expected one worker record, got %d", len(records))
+	}
+	hr := records[0].Hashrate(60)
+	if hr != 0 {
+		t.Fatalf("expected zero hashrate for worker with no accepts, got %f", hr)
+	}
+}
+
+func TestWorker_CustomDiffOrdering_Good(t *testing.T) {
+	cfg := &Config{
+		Mode:          "nicehash",
+		Workers:       WorkersByUser,
+		Bind:          []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:         []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		CustomDiff:    50000,
+		AccessLogFile: "",
+	}
+
+	p, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected valid proxy, got error: %v", result.Error)
+	}
+
+	miner := &Miner{
+		id:   21,
+		user: "WALLET+50000",
+		ip:   "10.0.0.3",
+		conn: noopConn{},
+	}
+	p.events.Dispatch(Event{Type: EventLogin, Miner: miner})
+
+	records := p.WorkerRecords()
+	if len(records) != 1 {
+		t.Fatalf("expected one worker record, got %d", len(records))
+	}
+	if records[0].Name != "WALLET" {
+		t.Fatalf("expected custom diff login suffix to be stripped before worker registration, got %q", records[0].Name)
+	}
+	if miner.User() != "WALLET" {
+		t.Fatalf("expected miner user to be stripped before downstream consumers, got %q", miner.User())
+	}
+}