fix: signal-backed marker reactivity and stale signal re-push

Two issues discovered during testing:

1. data-effect expressions for signal-backed markers short-circuited
   before reading $signalID when the map hadn't loaded yet. Datastar
   never tracked those signals as dependencies, so the effect never
   re-ran. Fix: read signal values unconditionally before the guard.

2. prepareSignalsForPatch never reset changed=false on regular signals
   (only computed ones), causing every SyncSignals() call to re-push
   all signals — including stale server-side values for the draggable
   pin, overwriting the client-side drag position.

.claude/commands/pr.md

@@ -8,7 +8,7 @@ Create a PR on Gitea, wait for CI, and squash-merge it. Push code to both remote
 5. Create a Gitea PR: `tea pr create --head <branch> --base main`. Reference related issues with `#X`. Only use `Closes #X` if the PR fully resolves the issue.
 6. Wait for CI to pass: poll Gitea CI status. If CI fails, report the failure and stop — do not merge.
 7. Once CI passes, squash-merge on Gitea: `tea pr merge <index> --style squash` with a clean, semantic commit message including the PR number. No Claude attribution lines.
-8. Update local main and push to both remotes. If in a worktree, `main` is checked out in the primary tree, so run from there: `cd <primary-worktree> && git pull gitea main && git push origin main` (the primary worktree path is the repo root without `.claude/worktrees/…`). If not in a worktree: `git checkout main && git pull gitea main && git push origin main`.
+8. Update local main and push to both remotes: `git checkout main && git pull gitea main && git push origin main`.
 9. Clean up remote branches: `git push gitea --delete <branch> && git push origin --delete <branch>`.
 10. Prune refs: `git remote prune gitea && git remote prune origin`.
 11. Report the merged PR URL.

configuration.go

@@ -1,6 +1,8 @@
 package via
 
 import (
+	"time"
+
 	"github.com/alexedwards/scs/v2"
 	"github.com/rs/zerolog"
 )
@@ -60,6 +62,16 @@ type Options struct {
 	// the embedded NATS server. Ignored when a custom PubSub is configured.
 	Streams []StreamConfig
 
+	// ContextSuspendAfter is the time a context may be disconnected before
+	// the reaper suspends it (frees page resources but keeps the context
+	// shell for seamless re-init on reconnect). Default: 15m.
+	ContextSuspendAfter time.Duration
+
+	// ContextTTL is the maximum time a context may exist without an SSE
+	// connection before the background reaper fully disposes it.
+	// Default: 1h. Negative value disables the reaper.
+	ContextTTL time.Duration
+
 	// ActionRateLimit configures the default token-bucket rate limiter for
 	// action endpoints. Zero values use built-in defaults (10 req/s, burst 20).
 	// Set Rate to -1 to disable rate limiting entirely.

context.go

@@ -25,7 +25,7 @@ type Context struct {
 	app               *V
 	view              func() h.H
 	routeParams       map[string]string
-	parentPageCtx     *Context
+	parentPageCtx *Context
 	patchChan         chan patch
 	actionLimiter     *rate.Limiter
 	actionRegistry    map[string]actionEntry
@@ -39,9 +39,11 @@ type Context struct {
 	subscriptions     []Subscription
 	subsMu            sync.Mutex
 	disposeOnce       sync.Once
-	createdAt         time.Time
-	sseConnected      atomic.Bool
-	sseDisconnectedAt atomic.Pointer[time.Time]
+	createdAt           time.Time
+	sseConnected        atomic.Bool
+	sseDisconnectedAt   atomic.Pointer[time.Time]
+	lastSeenAt          atomic.Pointer[time.Time]
+	suspended           atomic.Bool
 }
 
 // View defines the UI rendered by this context.
@@ -442,6 +444,13 @@ func (c *Context) resetPageState() {
 	c.mu.Unlock()
 }
 
+// suspend frees page-scoped resources while keeping the context shell alive
+// in the registry for seamless re-init on reconnect.
+func (c *Context) suspend() {
+	c.resetPageState()
+	c.suspended.Store(true)
+}
+
 // Navigate performs an SPA navigation to the given path. It resets page state,
 // runs the target page's init function (with middleware), and pushes the new
 // view over the existing SSE connection with a view transition animation.
@@ -630,17 +639,17 @@ func newContext(id string, route string, v *V) *Context {
 	}
 
 	return &Context{
-		id:              id,
-		route:           route,
-		csrfToken:       genCSRFToken(),
-		routeParams:     make(map[string]string),
-		app:             v,
-		actionLimiter:   newLimiter(v.actionRateLimit, defaultActionRate, defaultActionBurst),
-		actionRegistry:  make(map[string]actionEntry),
-		signals:         new(sync.Map),
-		patchChan:       make(chan patch, 8),
-		ctxDisposedChan: make(chan struct{}, 1),
-		pageStopChan:    make(chan struct{}),
-		createdAt:       time.Now(),
+		id:                id,
+		route:             route,
+		csrfToken:         genCSRFToken(),
+		routeParams:       make(map[string]string),
+		app:               v,
+		actionLimiter: newLimiter(v.actionRateLimit, defaultActionRate, defaultActionBurst),
+		actionRegistry:    make(map[string]actionEntry),
+		signals:           new(sync.Map),
+		patchChan:         make(chan patch, 8),
+		ctxDisposedChan:   make(chan struct{}, 1),
+		pageStopChan:      make(chan struct{}),
+		createdAt:         time.Now(),
 	}
 }

docs/getting-started.md

@@ -66,6 +66,7 @@ v.Config(via.Options{
     Plugins:         []via.Plugin{MyPlugin},
     SessionManager:  sm,
     PubSub:          customBackend,
+    ContextTTL:      60 * time.Second,
     ActionRateLimit: via.RateLimitConfig{Rate: 20, Burst: 40},
 })
 ```
@@ -82,6 +83,7 @@ v.Config(via.Options{
 | `DatastarContent` | (embedded) | Custom Datastar JS bytes |
 | `DatastarPath` | `"/_datastar.js"` | URL path for the Datastar script |
 | `PubSub` | embedded NATS | Custom PubSub backend. Replaces the default NATS. See [PubSub and Sessions](pubsub-and-sessions.md) |
+| `ContextTTL` | `30s` | Max time a context survives without an SSE connection before cleanup. Negative value disables the reaper |
 | `ActionRateLimit` | `10 req/s, burst 20` | Default token-bucket rate limiter for action endpoints. Rate of `-1` disables limiting |
 
 ## Static Files

docs/state-and-interactivity.md

@@ -14,7 +14,7 @@ Browser hits page → new Context created → init function runs → HTML render
                         action fires → signals injected from browser → handler runs → Sync() → DOM patched
 ```
 
-The context lives until the browser tab closes (detected via a `beforeunload` beacon) or the server shuts down. There is no background reaper — contexts persist across temporary SSE disconnections so backgrounded tabs resume seamlessly.
+The context is disposed when the SSE connection closes (tab close, navigation away, network loss). A background reaper also cleans up contexts that never establish an SSE connection within `ContextTTL` (default 30s).
 
 During [SPA navigation](routing-and-navigation.md#spa-navigation), the context itself survives — only page-level state (signals, actions, fields, intervals, subscriptions) is reset. The SSE connection persists.
 

internal/examples/realtimechart/main.go

@@ -15,8 +15,8 @@ func main() {
 
 	v.Config(via.Options{
 		LogLevel: via.LogLevelDebug,
-		DevMode:  true,
-		Plugins:  []via.Plugin{
+		DevMode: true,
+		Plugins: []via.Plugin{
 			// picocss.Default,
 		},
 	})

internal/examples/shakespeare/main.go

@@ -6,9 +6,9 @@ import (
 	"log"
 	"time"
 
-	_ "github.com/mattn/go-sqlite3"
 	"github.com/ryanhamamura/via"
 	"github.com/ryanhamamura/via/h"
+	_ "github.com/mattn/go-sqlite3"
 )
 
 type DataSource interface {

maplibre/types.go

@@ -316,7 +316,7 @@ type Marker struct {
 type Popup struct {
 	Content         string // HTML content
 	LngLat          LngLat
-	HideCloseButton bool // true removes the close button (MapLibre shows it by default)
+	HideCloseButton bool   // true removes the close button (MapLibre shows it by default)
 	MaxWidth        string
 }
 

signal.go

@@ -80,3 +80,4 @@ func (s *Signal) Int() int {
 	}
 	return 0
 }
+

static_test.go

@@ -81,8 +81,8 @@ func TestStaticAutoSlash(t *testing.T) {
 
 func TestStaticFS(t *testing.T) {
 	fsys := fstest.MapFS{
-		"style.css": {Data: []byte("body{}")},
-		"js/app.js": {Data: []byte("console.log('hi')")},
+		"style.css":        {Data: []byte("body{}")},
+		"js/app.js":        {Data: []byte("console.log('hi')")},
 	}
 
 	v := New()

via.go

@@ -58,6 +58,7 @@ type V struct {
 	datastarPath         string
 	datastarContent      []byte
 	datastarOnce         sync.Once
+	reaperStop           chan struct{}
 	middleware           []Middleware
 	layout               func(func() h.H) h.H
 }
@@ -138,6 +139,12 @@ func (v *V) Config(cfg Options) {
 		v.defaultNATS = nil
 		v.pubsub = cfg.PubSub
 	}
+	if cfg.ContextSuspendAfter != 0 {
+		v.cfg.ContextSuspendAfter = cfg.ContextSuspendAfter
+	}
+	if cfg.ContextTTL != 0 {
+		v.cfg.ContextTTL = cfg.ContextTTL
+	}
 	if cfg.Streams != nil {
 		v.cfg.Streams = cfg.Streams
 	}
@@ -240,10 +247,10 @@ func (v *V) page(route string, raw, wrapped func(*Context)) {
 			bodyElements = append(bodyElements, h.Raw("<dataspa-inspector/>"))
 		}
 		view := h.HTML5(h.HTML5Props{
-			Title: v.cfg.DocumentTitle,
-			Head:  headElements,
-			Body:  bodyElements,
-		})
+			Title:     v.cfg.DocumentTitle,
+			Head:      headElements,
+			Body:      bodyElements,
+			})
 		_ = view.Render(w)
 	}))
 }
@@ -285,6 +292,75 @@ func (v *V) getCtx(id string) (*Context, error) {
 	return nil, fmt.Errorf("ctx '%s' not found", id)
 }
 
+func (v *V) startReaper() {
+	ttl := v.cfg.ContextTTL
+	if ttl < 0 {
+		return
+	}
+	if ttl == 0 {
+		ttl = time.Hour
+	}
+	suspendAfter := v.cfg.ContextSuspendAfter
+	if suspendAfter == 0 {
+		suspendAfter = 15 * time.Minute
+	}
+	if suspendAfter > ttl {
+		suspendAfter = ttl
+	}
+	interval := suspendAfter / 3
+	if interval < 5*time.Second {
+		interval = 5 * time.Second
+	}
+	v.reaperStop = make(chan struct{})
+	go func() {
+		ticker := time.NewTicker(interval)
+		defer ticker.Stop()
+		for {
+			select {
+			case <-v.reaperStop:
+				return
+			case <-ticker.C:
+				v.reapOrphanedContexts(suspendAfter, ttl)
+			}
+		}
+	}()
+}
+
+func (v *V) reapOrphanedContexts(suspendAfter, ttl time.Duration) {
+	now := time.Now()
+	v.contextRegistryMutex.RLock()
+	var toSuspend, toReap []*Context
+	for _, c := range v.contextRegistry {
+		if c.sseConnected.Load() {
+			continue
+		}
+		// Use the most recent liveness signal
+		lastAlive := c.createdAt
+		if dc := c.sseDisconnectedAt.Load(); dc != nil && dc.After(lastAlive) {
+			lastAlive = *dc
+		}
+		if seen := c.lastSeenAt.Load(); seen != nil && seen.After(lastAlive) {
+			lastAlive = *seen
+		}
+		silentFor := now.Sub(lastAlive)
+		if silentFor > ttl {
+			toReap = append(toReap, c)
+		} else if silentFor > suspendAfter && !c.suspended.Load() {
+			toSuspend = append(toSuspend, c)
+		}
+	}
+	v.contextRegistryMutex.RUnlock()
+
+	for _, c := range toSuspend {
+		v.logInfo(c, "suspending context (no SSE connection after %s)", suspendAfter)
+		c.suspend()
+	}
+	for _, c := range toReap {
+		v.logInfo(c, "reaping orphaned context (no SSE connection after %s)", ttl)
+		v.cleanupCtx(c)
+	}
+}
+
 // Start starts the Via HTTP server and blocks until a SIGINT or SIGTERM
 // signal is received, then performs a graceful shutdown.
 func (v *V) Start() {
@@ -313,6 +389,8 @@ func (v *V) Start() {
 		Handler: handler,
 	}
 
+	v.startReaper()
+
 	errCh := make(chan error, 1)
 	go func() {
 		errCh <- v.server.ListenAndServe()
@@ -339,6 +417,9 @@ func (v *V) Start() {
 // Shutdown gracefully shuts down the server and all contexts.
 // Safe for programmatic or test use.
 func (v *V) Shutdown() {
+	if v.reaperStop != nil {
+		close(v.reaperStop)
+	}
 	v.logInfo(nil, "draining all contexts")
 	v.drainAllContexts()
 
@@ -586,6 +667,8 @@ func New() *V {
 			return
 		}
 		c.reqCtx = r.Context()
+		now := time.Now()
+		c.lastSeenAt.Store(&now)
 
 		sse := datastar.NewSSE(w, r, datastar.WithCompression(datastar.WithBrotli(datastar.WithBrotliLevel(5))))
 
@@ -607,6 +690,16 @@ func New() *V {
 		c.sseDisconnectedAt.Store(nil)
 		v.logDebug(c, "SSE connection established")
 
+		if c.suspended.Load() {
+			c.navMu.Lock()
+			c.suspended.Store(false)
+			if initFn := v.pageRegistry[c.route]; initFn != nil {
+				v.logInfo(c, "resuming suspended context")
+				initFn(c)
+			}
+			c.navMu.Unlock()
+		}
+
 		go c.Sync()
 
 		keepalive := time.NewTicker(30 * time.Second)

via_test.go

@@ -134,9 +134,9 @@ func TestAction(t *testing.T) {
 
 func TestEventTypes(t *testing.T) {
 	tests := []struct {
-		name    string
-		attr    string
-		buildEl func(trigger *actionTrigger) h.H
+		name     string
+		attr     string
+		buildEl  func(trigger *actionTrigger) h.H
 	}{
 		{"OnSubmit", "data-on:submit", func(tr *actionTrigger) h.H { return h.Form(tr.OnSubmit()) }},
 		{"OnInput", "data-on:input", func(tr *actionTrigger) h.H { return h.Input(tr.OnInput()) }},
@@ -400,6 +400,95 @@ func TestPage_PanicsOnNoView(t *testing.T) {
 	})
 }
 
+func TestReaperCleansOrphanedContexts(t *testing.T) {
+	v := New()
+	c := newContext("orphan-1", "/", v)
+	c.createdAt = time.Now().Add(-time.Minute) // created 1 min ago
+	v.registerCtx(c)
+
+	_, err := v.getCtx("orphan-1")
+	assert.NoError(t, err)
+
+	v.reapOrphanedContexts(5*time.Second, 10*time.Second)
+
+	_, err = v.getCtx("orphan-1")
+	assert.Error(t, err, "orphaned context should have been reaped")
+}
+
+func TestReaperSuspendsContext(t *testing.T) {
+	v := New()
+	c := newContext("suspend-1", "/", v)
+	c.createdAt = time.Now().Add(-30 * time.Minute)
+	dc := time.Now().Add(-20 * time.Minute)
+	c.sseDisconnectedAt.Store(&dc)
+	v.registerCtx(c)
+
+	v.reapOrphanedContexts(15*time.Minute, time.Hour)
+
+	got, err := v.getCtx("suspend-1")
+	assert.NoError(t, err, "suspended context should still be in registry")
+	assert.True(t, got.suspended.Load(), "context should be marked suspended")
+}
+
+func TestReaperReapsAfterTTL(t *testing.T) {
+	v := New()
+	c := newContext("reap-1", "/", v)
+	c.createdAt = time.Now().Add(-3 * time.Hour)
+	dc := time.Now().Add(-2 * time.Hour)
+	c.sseDisconnectedAt.Store(&dc)
+	c.suspended.Store(true)
+	v.registerCtx(c)
+
+	v.reapOrphanedContexts(15*time.Minute, time.Hour)
+
+	_, err := v.getCtx("reap-1")
+	assert.Error(t, err, "context past TTL should have been reaped")
+}
+
+func TestReaperIgnoresAlreadySuspended(t *testing.T) {
+	v := New()
+	c := newContext("already-sus-1", "/", v)
+	c.createdAt = time.Now().Add(-30 * time.Minute)
+	dc := time.Now().Add(-20 * time.Minute)
+	c.sseDisconnectedAt.Store(&dc)
+	c.suspended.Store(true)
+	// give it a fresh pageStopChan so we can verify it's not re-closed
+	c.pageStopChan = make(chan struct{})
+	v.registerCtx(c)
+
+	v.reapOrphanedContexts(15*time.Minute, time.Hour)
+
+	got, err := v.getCtx("already-sus-1")
+	assert.NoError(t, err, "already-suspended context within TTL should survive")
+	assert.True(t, got.suspended.Load())
+	// pageStopChan should still be open (not re-suspended)
+	select {
+	case <-got.pageStopChan:
+		t.Fatal("pageStopChan was closed — context was re-suspended")
+	default:
+	}
+}
+
+func TestReaperIgnoresConnectedContexts(t *testing.T) {
+	v := New()
+	c := newContext("connected-1", "/", v)
+	c.createdAt = time.Now().Add(-time.Minute)
+	c.sseConnected.Store(true)
+	v.registerCtx(c)
+
+	v.reapOrphanedContexts(5*time.Second, 10*time.Second)
+
+	_, err := v.getCtx("connected-1")
+	assert.NoError(t, err, "connected context should survive reaping")
+}
+
+func TestReaperDisabledWithNegativeTTL(t *testing.T) {
+	v := New()
+	v.cfg.ContextTTL = -1
+	v.startReaper()
+	assert.Nil(t, v.reaperStop, "reaper should not start with negative TTL")
+}
+
 func TestCleanupCtxIdempotent(t *testing.T) {
 	v := New()
 	c := newContext("idempotent-1", "/", v)
@@ -414,6 +503,74 @@ func TestCleanupCtxIdempotent(t *testing.T) {
 	assert.Error(t, err, "context should be removed after cleanup")
 }
 
+func TestReaperRespectsLastSeenAt(t *testing.T) {
+	v := New()
+	c := newContext("seen-1", "/", v)
+	c.createdAt = time.Now().Add(-30 * time.Minute)
+	// Disconnected 20 min ago, but client retried (lastSeenAt) 2 min ago
+	dc := time.Now().Add(-20 * time.Minute)
+	c.sseDisconnectedAt.Store(&dc)
+	seen := time.Now().Add(-2 * time.Minute)
+	c.lastSeenAt.Store(&seen)
+	v.registerCtx(c)
+
+	v.reapOrphanedContexts(15*time.Minute, time.Hour)
+
+	_, err := v.getCtx("seen-1")
+	assert.NoError(t, err, "context with recent lastSeenAt should survive suspend threshold")
+	assert.False(t, c.suspended.Load(), "context should not be suspended")
+}
+
+func TestReaperFallsBackWithoutLastSeenAt(t *testing.T) {
+	v := New()
+	c := newContext("noseen-1", "/", v)
+	c.createdAt = time.Now().Add(-30 * time.Minute)
+	dc := time.Now().Add(-20 * time.Minute)
+	c.sseDisconnectedAt.Store(&dc)
+	// no lastSeenAt set — should fall back to sseDisconnectedAt
+	v.registerCtx(c)
+
+	v.reapOrphanedContexts(15*time.Minute, time.Hour)
+
+	got, err := v.getCtx("noseen-1")
+	assert.NoError(t, err, "context should still be in registry (suspended, not reaped)")
+	assert.True(t, got.suspended.Load(), "context should be suspended using sseDisconnectedAt fallback")
+}
+
+func TestReaperReapsWithStaleLastSeenAt(t *testing.T) {
+	v := New()
+	c := newContext("stale-seen-1", "/", v)
+	c.createdAt = time.Now().Add(-3 * time.Hour)
+	dc := time.Now().Add(-2 * time.Hour)
+	c.sseDisconnectedAt.Store(&dc)
+	// lastSeenAt is also old — beyond TTL
+	seen := time.Now().Add(-90 * time.Minute)
+	c.lastSeenAt.Store(&seen)
+	c.suspended.Store(true)
+	v.registerCtx(c)
+
+	v.reapOrphanedContexts(15*time.Minute, time.Hour)
+
+	_, err := v.getCtx("stale-seen-1")
+	assert.Error(t, err, "context with stale lastSeenAt beyond TTL should be reaped")
+}
+
+func TestLastSeenAtUpdatedOnSSEConnect(t *testing.T) {
+	v := New()
+	c := newContext("seen-sse-1", "/", v)
+	v.registerCtx(c)
+
+	assert.Nil(t, c.lastSeenAt.Load(), "lastSeenAt should be nil before SSE connect")
+
+	// Simulate what the SSE handler does after getCtx
+	now := time.Now()
+	c.lastSeenAt.Store(&now)
+
+	got := c.lastSeenAt.Load()
+	assert.NotNil(t, got, "lastSeenAt should be set after SSE connect")
+	assert.WithinDuration(t, now, *got, time.Second)
+}
+
 func TestDevModeRemovePersistedFix(t *testing.T) {
 	v := New()
 	v.cfg.DevMode = true