diff --git a/api/router.go b/api/router.go
index 41b54b5..8331a58 100644
--- a/api/router.go
+++ b/api/router.go
@@ -25,13 +25,14 @@ type Router interface {
 //
 //	{"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"`
+	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"`
+	CustomDiffStats map[uint64]proxy.CustomDiffBucketStats `json:"custom_diff_stats,omitempty"`
 }
 
 // HashrateResponse carries the per-window hashrate array.
@@ -100,6 +101,7 @@ func summaryResponse(p *proxy.Proxy) SummaryResponse {
 		Hashrate: HashrateResponse{
 			Total: summary.Hashrate,
 		},
+		CustomDiffStats: summary.CustomDiffStats,
 		Miners: MinersCountResponse{
 			Now: now,
 			Max: max,
diff --git a/customdiffstats.go b/customdiffstats.go
new file mode 100644
index 0000000..5ea9ed3
--- /dev/null
+++ b/customdiffstats.go
@@ -0,0 +1,108 @@
+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"`
+	Hashes   uint64 `json:"hashes_total"`
+}
+
+// CustomDiffBuckets records share totals grouped by miner custom difficulty.
+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.Hashes += 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.
+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)
+	return strings.Contains(reason, "difficulty") || strings.Contains(reason, "invalid") || strings.Contains(reason, "nonce")
+}
diff --git a/customdiffstats_test.go b/customdiffstats_test.go
new file mode 100644
index 0000000..7b5aef8
--- /dev/null
+++ b/customdiffstats_test.go
@@ -0,0 +1,77 @@
+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.Hashes != 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: "Invalid nonce"})
+
+	summary := p.Summary()
+	bucket, ok := summary.CustomDiffStats[10000]
+	if !ok {
+		t.Fatalf("expected custom diff bucket 10000 to be present")
+	}
+	if bucket.Rejected != 1 || bucket.Invalid != 1 {
+		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)
+	}
+}
diff --git a/pool/impl.go b/pool/impl.go
index ef6e9c2..bf48b03 100644
--- a/pool/impl.go
+++ b/pool/impl.go
@@ -350,6 +350,7 @@ func (s *FailoverStrategy) Connect() {
 	}
 	s.mu.Lock()
 	defer s.mu.Unlock()
+	s.closing = false
 	s.connectLocked(0)
 }
 
@@ -408,10 +409,12 @@ func (s *FailoverStrategy) Disconnect() {
 		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()
 	}
 }
 
@@ -452,6 +455,15 @@ func (s *FailoverStrategy) OnDisconnect() {
 	if s == nil {
 		return
 	}
+	s.mu.Lock()
+	closing := s.closing
+	if closing {
+		s.closing = false
+	}
+	s.mu.Unlock()
+	if closing {
+		return
+	}
 	if s.listener != nil {
 		s.listener.OnDisconnect()
 	}
diff --git a/pool/strategy.go b/pool/strategy.go
index 92b2efb..c9e1986 100644
--- a/pool/strategy.go
+++ b/pool/strategy.go
@@ -18,6 +18,7 @@ type FailoverStrategy struct {
 	client   *StratumClient
 	listener StratumListener
 	cfg      *proxy.Config
+	closing  bool
 	mu       sync.Mutex
 }
 
diff --git a/pool/strategy_disconnect_test.go b/pool/strategy_disconnect_test.go
new file mode 100644
index 0000000..de9a173
--- /dev/null
+++ b/pool/strategy_disconnect_test.go
@@ -0,0 +1,65 @@
+package pool
+
+import (
+	"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)
+	}
+}
diff --git a/proxy.go b/proxy.go
index 35d994a..813911d 100644
--- a/proxy.go
+++ b/proxy.go
@@ -23,23 +23,24 @@ import (
 //	p, result := proxy.New(cfg)
 //	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
-	accessLog   *accessLogSink
-	submitCount atomic.Int64
+	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
+	customDiffBuckets *CustomDiffBuckets
+	rateLimit         *RateLimiter
+	httpServer        *http.Server
+	accessLog         *accessLogSink
+	submitCount       atomic.Int64
 }
 
 // Splitter is the interface both NonceSplitter and SimpleSplitter satisfy.
diff --git a/state_impl.go b/state_impl.go
index 45febe1..2835141 100644
--- a/state_impl.go
+++ b/state_impl.go
@@ -39,15 +39,16 @@ func New(cfg *Config) (*Proxy, Result) {
 	}
 
 	p := &Proxy{
-		config:     cfg,
-		events:     NewEventBus(),
-		stats:      NewStats(),
-		workers:    NewWorkers(cfg.Workers, nil),
-		miners:     make(map[int64]*Miner),
-		customDiff: NewCustomDiff(cfg.CustomDiff),
-		rateLimit:  NewRateLimiter(cfg.RateLimit),
-		accessLog:  newAccessLogSink(cfg.AccessLogFile),
-		done:       make(chan struct{}),
+		config:            cfg,
+		events:            NewEventBus(),
+		stats:             NewStats(),
+		workers:           NewWorkers(cfg.Workers, nil),
+		miners:            make(map[int64]*Miner),
+		customDiff:        NewCustomDiff(cfg.CustomDiff),
+		customDiffBuckets: NewCustomDiffBuckets(cfg.CustomDiffStats),
+		rateLimit:         NewRateLimiter(cfg.RateLimit),
+		accessLog:         newAccessLogSink(cfg.AccessLogFile),
+		done:              make(chan struct{}),
 	}
 	p.workers.bindEvents(p.events)
 
@@ -60,6 +61,10 @@ func New(cfg *Config) (*Proxy, Result) {
 	p.events.Subscribe(EventClose, p.stats.OnClose)
 	p.events.Subscribe(EventAccept, p.stats.OnAccept)
 	p.events.Subscribe(EventReject, p.stats.OnReject)
+	if p.customDiffBuckets != nil {
+		p.events.Subscribe(EventAccept, p.customDiffBuckets.OnAccept)
+		p.events.Subscribe(EventReject, p.customDiffBuckets.OnReject)
+	}
 	if cfg.Watch && cfg.sourcePath != "" {
 		p.watcher = NewConfigWatcher(cfg.sourcePath, p.Reload)
 	}
@@ -94,7 +99,11 @@ func (p *Proxy) Summary() StatsSummary {
 	if p == nil || p.stats == nil {
 		return StatsSummary{}
 	}
-	return p.stats.Summary()
+	summary := p.stats.Summary()
+	if p.customDiffBuckets != nil {
+		summary.CustomDiffStats = p.customDiffBuckets.Snapshot()
+	}
+	return summary
 }
 
 // WorkerRecords returns a stable snapshot of worker rows.
@@ -274,6 +283,9 @@ func (p *Proxy) Reload(cfg *Config) {
 	if p.customDiff != nil {
 		p.customDiff.globalDiff = cfg.CustomDiff
 	}
+	if p.customDiffBuckets != nil {
+		p.customDiffBuckets.SetEnabled(cfg.CustomDiffStats)
+	}
 	p.rateLimit = NewRateLimiter(cfg.RateLimit)
 	for _, server := range p.servers {
 		if server != nil {
@@ -499,6 +511,7 @@ func (p *Proxy) summaryDocument() any {
 		"hashrate": map[string]any{
 			"total": summary.Hashrate,
 		},
+		"custom_diff_stats": summary.CustomDiffStats,
 		"miners": map[string]any{
 			"now": now,
 			"max": max,
diff --git a/stats.go b/stats.go
index ca5e536..f516767 100644
--- a/stats.go
+++ b/stats.go
@@ -49,13 +49,14 @@ type tickWindow struct {
 //
 //	summary := stats.Summary()
 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"`
 }