WIP

packages/svelte/src/internal/client/reactivity/deriveds.js

@@ -87,7 +87,7 @@ export function derived(fn) {
 		f: flags,
 		fn,
 		reactions: null,
-		rv: 0,
+		rv: -1,
 		v: /** @type {V} */ (UNINITIALIZED),
 		wv: 0,
 		parent: parent_derived ?? active_effect,

packages/svelte/src/internal/client/reactivity/utils.js

@@ -25,11 +25,12 @@ function clear_marked(deps) {
  * @param {Set<Effect>} maybe_dirty_effects
  */
 export function defer_effect(effect, dirty_effects, maybe_dirty_effects) {
-	if ((effect.f & DIRTY) !== 0) {
-		dirty_effects.add(effect);
-	} else if ((effect.f & MAYBE_DIRTY) !== 0) {
-		maybe_dirty_effects.add(effect);
-	}
+	dirty_effects.add(effect);
+
+	// if ((effect.f & DIRTY) !== 0) {
+	// } else if ((effect.f & MAYBE_DIRTY) !== 0) {
+	// 	maybe_dirty_effects.add(effect);
+	// }
 
 	// Since we're not executing these effects now, we need to clear any WAS_MARKED flags
 	// so that other batches can correctly reach these effects during their own traversal

packages/svelte/src/internal/client/runtime.js

@@ -156,6 +156,10 @@ export function increment_write_version() {
 export function is_dirty(reaction) {
 	var flags = reaction.f;
 
+	if ((flags & REACTION_RAN) === 0) {
+		return true;
+	}
+
 	if (flags & DERIVED) {
 		reaction.f &= ~WAS_MARKED;
 	}