chore: staticcheck and gofmt cleanups

1 files changed, 4 insertions, 1 deletions

diff --git a/internal/engine/tick.go b/internal/engine/tick.go
index 74b1dcf..63ee6af 100644
--- a/internal/engine/tick.go
+++ b/internal/engine/tick.go
@@ -99,8 +99,11 @@ func (e *Engine) Stop() {
 // before owned state is saved.
 func (e *Engine) StopAndWait() {
 	e.Stop()
+	// Join any in-flight tick: processTick holds tickMu for its whole body,
+	// so acquiring the mutex blocks until the running callback completes;
+	// holding it until return keeps that guarantee for the caller.
 	e.tickMu.Lock()
-	e.tickMu.Unlock()
+	defer e.tickMu.Unlock()
 }
 
 // Tick fires every due subscriber synchronously and returns. Subscribers