diff --git a/contract.go b/contract.go
index ddf0def..b5fd099 100644
--- a/contract.go
+++ b/contract.go
@@ -82,6 +82,7 @@ func New(opts ...Options) *Core {
 		log:      &ErrorLog{log: Default()},
 		lock:     &Lock{},
 		ipc:      &Ipc{},
+		info:     systemInfo,
 		i18n:     &I18n{},
 		services: &serviceRegistry{services: make(map[string]*Service)},
 		commands: &commandRegistry{commands: make(map[string]*Command)},
diff --git a/core.go b/core.go
index b02fc93..fb9c5d9 100644
--- a/core.go
+++ b/core.go
@@ -28,6 +28,7 @@ type Core struct {
 	services *serviceRegistry // c.Service("name")  — Service registry
 	lock     *Lock            // c.Lock("name")     — Named mutexes
 	ipc      *Ipc             // c.IPC()            — Message bus for IPC
+	info     *SysInfo         // c.Env("key")        — Read-only system/environment information
 	i18n     *I18n            // c.I18n()           — Internationalisation and locale collection
 
 	context       context.Context
@@ -51,6 +52,7 @@ func (c *Core) Log() *ErrorLog           { return c.log }
 func (c *Core) Cli() *Cli                { return c.cli }
 func (c *Core) IPC() *Ipc                { return c.ipc }
 func (c *Core) I18n() *I18n              { return c.i18n }
+func (c *Core) Env(key string) string    { return Env(key) }
 func (c *Core) Context() context.Context { return c.context }
 func (c *Core) Core() *Core              { return c }
 
diff --git a/info.go b/info.go
new file mode 100644
index 0000000..1a4ae43
--- /dev/null
+++ b/info.go
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: EUPL-1.2
+
+// System information registry for the Core framework.
+// Read-only key-value store of environment facts, populated once at init.
+// Env is environment. Config is ours.
+//
+// System keys:
+//
+//	core.Env("OS")        // "darwin"
+//	core.Env("ARCH")      // "arm64"
+//	core.Env("GO")        // "go1.26"
+//	core.Env("DS")        // "/" (directory separator)
+//	core.Env("PS")        // ":" (path list separator)
+//	core.Env("HOSTNAME")  // "cladius"
+//	core.Env("USER")      // "snider"
+//	core.Env("PID")       // "12345"
+//	core.Env("NUM_CPU")   // "10"
+//
+// Directory keys:
+//
+//	core.Env("DIR_HOME")      // "/Users/snider"
+//	core.Env("DIR_CONFIG")    // "~/Library/Application Support"
+//	core.Env("DIR_CACHE")     // "~/Library/Caches"
+//	core.Env("DIR_DATA")      // "~/Library" (platform-specific)
+//	core.Env("DIR_TMP")       // "/tmp"
+//	core.Env("DIR_CWD")       // current working directory
+//	core.Env("DIR_DOWNLOADS") // "~/Downloads"
+//	core.Env("DIR_CODE")      // "~/Code"
+//
+// Timestamp keys:
+//
+//	core.Env("CORE_START")  // "2026-03-22T14:30:00Z"
+package core
+
+import (
+	"os"
+	"runtime"
+	"strconv"
+	"time"
+)
+
+// SysInfo holds read-only system information, populated once at init.
+type SysInfo struct {
+	values map[string]string
+}
+
+// systemInfo is declared empty — populated in init() so Path() can be used
+// without creating an init cycle.
+var systemInfo = &SysInfo{values: make(map[string]string)}
+
+func init() {
+	i := systemInfo
+
+	// System
+	i.values["OS"] = runtime.GOOS
+	i.values["ARCH"] = runtime.GOARCH
+	i.values["GO"] = runtime.Version()
+	i.values["DS"] = string(os.PathSeparator)
+	i.values["PS"] = string(os.PathListSeparator)
+	i.values["PID"] = strconv.Itoa(os.Getpid())
+	i.values["NUM_CPU"] = strconv.Itoa(runtime.NumCPU())
+	i.values["USER"] = Username()
+
+	if h, err := os.Hostname(); err == nil {
+		i.values["HOSTNAME"] = h
+	}
+
+	// Directories — DS and DIR_HOME set first so Path() can use them.
+	// CORE_HOME overrides os.UserHomeDir() (e.g., agent workspaces).
+	if d := os.Getenv("CORE_HOME"); d != "" {
+		i.values["DIR_HOME"] = d
+	} else if d, err := os.UserHomeDir(); err == nil {
+		i.values["DIR_HOME"] = d
+	}
+
+	// Derived directories via Path() — single point of responsibility
+	i.values["DIR_DOWNLOADS"] = Path("Downloads")
+	i.values["DIR_CODE"] = Path("Code")
+	if d, err := os.UserConfigDir(); err == nil {
+		i.values["DIR_CONFIG"] = d
+	}
+	if d, err := os.UserCacheDir(); err == nil {
+		i.values["DIR_CACHE"] = d
+	}
+	i.values["DIR_TMP"] = os.TempDir()
+	if d, err := os.Getwd(); err == nil {
+		i.values["DIR_CWD"] = d
+	}
+
+	// Platform-specific data directory
+	switch runtime.GOOS {
+	case "darwin":
+		i.values["DIR_DATA"] = Path(Env("DIR_HOME"), "Library")
+	case "windows":
+		if d := os.Getenv("LOCALAPPDATA"); d != "" {
+			i.values["DIR_DATA"] = d
+		}
+	default:
+		if xdg := os.Getenv("XDG_DATA_HOME"); xdg != "" {
+			i.values["DIR_DATA"] = xdg
+		} else if Env("DIR_HOME") != "" {
+			i.values["DIR_DATA"] = Path(Env("DIR_HOME"), ".local", "share")
+		}
+	}
+
+	// Timestamps
+	i.values["CORE_START"] = time.Now().UTC().Format(time.RFC3339)
+}
+
+// Env returns a system information value by key.
+// Core keys (OS, DIR_HOME, DS, etc.) are pre-populated at init.
+// Unknown keys fall through to os.Getenv — making Env a universal
+// replacement for os.Getenv.
+//
+//	core.Env("OS")           // "darwin" (pre-populated)
+//	core.Env("DIR_HOME")     // "/Users/snider" (pre-populated)
+//	core.Env("FORGE_TOKEN")  // falls through to os.Getenv
+func Env(key string) string {
+	if v := systemInfo.values[key]; v != "" {
+		return v
+	}
+	return os.Getenv(key)
+}
+
+// EnvKeys returns all available environment keys.
+//
+//	keys := core.EnvKeys()
+func EnvKeys() []string {
+	keys := make([]string, 0, len(systemInfo.values))
+	for k := range systemInfo.values {
+		keys = append(keys, k)
+	}
+	return keys
+}
diff --git a/info_test.go b/info_test.go
new file mode 100644
index 0000000..5f09db7
--- /dev/null
+++ b/info_test.go
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: EUPL-1.2
+
+package core_test
+
+import (
+	"os"
+	"runtime"
+	"testing"
+	"time"
+
+	core "dappco.re/go/core"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestEnv_OS(t *testing.T) {
+	assert.Equal(t, runtime.GOOS, core.Env("OS"))
+}
+
+func TestEnv_ARCH(t *testing.T) {
+	assert.Equal(t, runtime.GOARCH, core.Env("ARCH"))
+}
+
+func TestEnv_GO(t *testing.T) {
+	assert.Equal(t, runtime.Version(), core.Env("GO"))
+}
+
+func TestEnv_DS(t *testing.T) {
+	assert.Equal(t, string(os.PathSeparator), core.Env("DS"))
+}
+
+func TestEnv_PS(t *testing.T) {
+	assert.Equal(t, string(os.PathListSeparator), core.Env("PS"))
+}
+
+func TestEnv_DIR_HOME(t *testing.T) {
+	if ch := os.Getenv("CORE_HOME"); ch != "" {
+		assert.Equal(t, ch, core.Env("DIR_HOME"))
+		return
+	}
+	home, err := os.UserHomeDir()
+	require.NoError(t, err)
+	assert.Equal(t, home, core.Env("DIR_HOME"))
+}
+
+func TestEnv_DIR_TMP(t *testing.T) {
+	assert.Equal(t, os.TempDir(), core.Env("DIR_TMP"))
+}
+
+func TestEnv_DIR_CONFIG(t *testing.T) {
+	cfg, err := os.UserConfigDir()
+	require.NoError(t, err)
+	assert.Equal(t, cfg, core.Env("DIR_CONFIG"))
+}
+
+func TestEnv_DIR_CACHE(t *testing.T) {
+	cache, err := os.UserCacheDir()
+	require.NoError(t, err)
+	assert.Equal(t, cache, core.Env("DIR_CACHE"))
+}
+
+func TestEnv_HOSTNAME(t *testing.T) {
+	hostname, err := os.Hostname()
+	require.NoError(t, err)
+	assert.Equal(t, hostname, core.Env("HOSTNAME"))
+}
+
+func TestEnv_USER(t *testing.T) {
+	assert.NotEmpty(t, core.Env("USER"))
+}
+
+func TestEnv_PID(t *testing.T) {
+	assert.NotEmpty(t, core.Env("PID"))
+}
+
+func TestEnv_NUM_CPU(t *testing.T) {
+	assert.NotEmpty(t, core.Env("NUM_CPU"))
+}
+
+func TestEnv_CORE_START(t *testing.T) {
+	ts := core.Env("CORE_START")
+	require.NotEmpty(t, ts)
+	_, err := time.Parse(time.RFC3339, ts)
+	assert.NoError(t, err, "CORE_START should be valid RFC3339")
+}
+
+func TestEnv_Unknown(t *testing.T) {
+	assert.Equal(t, "", core.Env("NOPE"))
+}
+
+func TestEnv_CoreInstance(t *testing.T) {
+	c := core.New()
+	assert.Equal(t, core.Env("OS"), c.Env("OS"))
+	assert.Equal(t, core.Env("DIR_HOME"), c.Env("DIR_HOME"))
+}
+
+func TestEnvKeys(t *testing.T) {
+	keys := core.EnvKeys()
+	assert.NotEmpty(t, keys)
+	assert.Contains(t, keys, "OS")
+	assert.Contains(t, keys, "DIR_HOME")
+	assert.Contains(t, keys, "CORE_START")
+}
diff --git a/path.go b/path.go
new file mode 100644
index 0000000..d977e9c
--- /dev/null
+++ b/path.go
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: EUPL-1.2
+
+// OS-aware filesystem path operations for the Core framework.
+// Uses Env("DS") for the separator and Core string primitives
+// for path manipulation. filepath imported only for PathGlob.
+//
+// Path anchors relative segments to DIR_HOME:
+//
+//	core.Path("Code", ".core")     // "/Users/snider/Code/.core"
+//	core.Path("/tmp", "workspace") // "/tmp/workspace"
+//	core.Path()                    // "/Users/snider"
+//
+// Path component helpers:
+//
+//	core.PathBase("/Users/snider/Code/core")  // "core"
+//	core.PathDir("/Users/snider/Code/core")   // "/Users/snider/Code"
+//	core.PathExt("main.go")                   // ".go"
+package core
+
+import "path/filepath"
+
+// Path builds a clean, absolute filesystem path from segments.
+// Uses Env("DS") for the OS directory separator.
+// Relative paths are anchored to DIR_HOME. Absolute paths pass through.
+//
+//	core.Path("Code", ".core")      // "/Users/snider/Code/.core"
+//	core.Path("/tmp", "workspace")  // "/tmp/workspace"
+//	core.Path()                     // "/Users/snider"
+func Path(segments ...string) string {
+	ds := Env("DS")
+	home := Env("DIR_HOME")
+	if home == "" {
+		home = "."
+	}
+	if len(segments) == 0 {
+		return home
+	}
+	p := Join(ds, segments...)
+	if PathIsAbs(p) {
+		return CleanPath(p, ds)
+	}
+	return CleanPath(home+ds+p, ds)
+}
+
+// PathBase returns the last element of a path.
+//
+//	core.PathBase("/Users/snider/Code/core")  // "core"
+//	core.PathBase("deploy/to/homelab")        // "homelab"
+func PathBase(p string) string {
+	if p == "" {
+		return "."
+	}
+	ds := Env("DS")
+	p = TrimSuffix(p, ds)
+	if p == "" {
+		return ds
+	}
+	parts := Split(p, ds)
+	return parts[len(parts)-1]
+}
+
+// PathDir returns all but the last element of a path.
+//
+//	core.PathDir("/Users/snider/Code/core")  // "/Users/snider/Code"
+func PathDir(p string) string {
+	if p == "" {
+		return "."
+	}
+	ds := Env("DS")
+	i := lastIndex(p, ds)
+	if i < 0 {
+		return "."
+	}
+	dir := p[:i]
+	if dir == "" {
+		return ds
+	}
+	return dir
+}
+
+// PathExt returns the file extension including the dot.
+//
+//	core.PathExt("main.go")   // ".go"
+//	core.PathExt("Makefile")  // ""
+func PathExt(p string) string {
+	base := PathBase(p)
+	i := lastIndex(base, ".")
+	if i <= 0 {
+		return ""
+	}
+	return base[i:]
+}
+
+// PathIsAbs returns true if the path is absolute.
+// Handles Unix (starts with /) and Windows (drive letter like C:).
+//
+//	core.PathIsAbs("/tmp")     // true
+//	core.PathIsAbs("C:\\tmp")  // true
+//	core.PathIsAbs("relative") // false
+func PathIsAbs(p string) bool {
+	if p == "" {
+		return false
+	}
+	if p[0] == '/' {
+		return true
+	}
+	// Windows: C:\ or C:/
+	if len(p) >= 3 && p[1] == ':' && (p[2] == '/' || p[2] == '\\') {
+		return true
+	}
+	return false
+}
+
+// CleanPath removes redundant separators and resolves . and .. elements.
+//
+//	core.CleanPath("/tmp//file", "/")     // "/tmp/file"
+//	core.CleanPath("a/b/../c", "/")       // "a/c"
+func CleanPath(p, ds string) string {
+	if p == "" {
+		return "."
+	}
+
+	rooted := HasPrefix(p, ds)
+	parts := Split(p, ds)
+	var clean []string
+
+	for _, part := range parts {
+		switch part {
+		case "", ".":
+			continue
+		case "..":
+			if len(clean) > 0 && clean[len(clean)-1] != ".." {
+				clean = clean[:len(clean)-1]
+			} else if !rooted {
+				clean = append(clean, "..")
+			}
+		default:
+			clean = append(clean, part)
+		}
+	}
+
+	result := Join(ds, clean...)
+	if rooted {
+		result = ds + result
+	}
+	if result == "" {
+		if rooted {
+			return ds
+		}
+		return "."
+	}
+	return result
+}
+
+// PathGlob returns file paths matching a pattern.
+//
+//	core.PathGlob("/tmp/agent-*.log")
+func PathGlob(pattern string) []string {
+	matches, _ := filepath.Glob(pattern)
+	return matches
+}
+
+// lastIndex returns the index of the last occurrence of substr in s, or -1.
+func lastIndex(s, substr string) int {
+	if substr == "" || s == "" {
+		return -1
+	}
+	for i := len(s) - len(substr); i >= 0; i-- {
+		if s[i:i+len(substr)] == substr {
+			return i
+		}
+	}
+	return -1
+}
diff --git a/path_test.go b/path_test.go
index ad78e5b..fdc8725 100644
--- a/path_test.go
+++ b/path_test.go
@@ -106,7 +106,6 @@ func TestCleanPath_Good(t *testing.T) {
 }
 
 func TestPathDir_TrailingSlash(t *testing.T) {
-	// Trailing slash is stripped, then dir of /Users/snider/Code = /Users/snider
 	result := core.PathDir("/Users/snider/Code/")
 	assert.Equal(t, "/Users/snider/Code", result)
 }