diff --git a/packages/svelte/src/compiler/phases/3-transform/client/visitors/template.js b/packages/svelte/src/compiler/phases/3-transform/client/visitors/template.js
index feb9174187a0..091cf74442b0 100644
--- a/packages/svelte/src/compiler/phases/3-transform/client/visitors/template.js
+++ b/packages/svelte/src/compiler/phases/3-transform/client/visitors/template.js
@@ -795,31 +795,51 @@ function serialize_inline_component(node, component_name, context) {
 				push_prop(
 					b.get(attribute.name, [
 						b.return(
-							b.call(
-								'$.exposable',
-								b.thunk(
-									/** @type {import('estree').Expression} */ (context.visit(attribute.expression))
-								)
-							)
+							context.state.analysis.immutable
+								? /** @type {import('estree').Expression} */ (context.visit(attribute.expression))
+								: b.call(
+										'$.exposable',
+										b.thunk(
+											/** @type {import('estree').Expression} */ (
+												context.visit(attribute.expression)
+											)
+										)
+								  )
 						)
 					])
 				);
-				// If the binding is just a reference to a top level state variable
-				// we don't need a setter as the inner component can write to the signal directly
-				const binding =
-					attribute.expression.type !== 'Identifier'
-						? null
-						: context.state.scope.get(attribute.expression.name);
-				if (
-					binding === null ||
-					(binding.kind !== 'state' && binding.kind !== 'prop' && binding.kind !== 'rest_prop')
-				) {
+
+				if (attribute.expression.type === 'Identifier') {
 					const assignment = b.assignment('=', attribute.expression, b.id('$$value'));
 					push_prop(
 						b.set(attribute.name, [
 							b.stmt(serialize_set_binding(assignment, context, () => context.visit(assignment)))
 						])
 					);
+				} else {
+					if (context.state.analysis.immutable) {
+						const assignment = b.assignment('=', attribute.expression, b.id('$$value'));
+						push_prop(
+							b.set(attribute.name, [
+								b.stmt(
+									b.assignment(
+										'=',
+										/** @type {import('estree').MemberExpression} */ (
+											context.visit(attribute.expression)
+										),
+										b.id('$$value')
+									)
+								)
+							])
+						);
+					} else {
+						const assignment = b.assignment('=', attribute.expression, b.id('$$value'));
+						push_prop(
+							b.set(attribute.name, [
+								b.stmt(serialize_set_binding(assignment, context, () => context.visit(assignment)))
+							])
+						);
+					}
 				}
 			}
 		}
diff --git a/packages/svelte/src/internal/client/runtime.js b/packages/svelte/src/internal/client/runtime.js
index 2d3e5204c733..a8ec627008d7 100644
--- a/packages/svelte/src/internal/client/runtime.js
+++ b/packages/svelte/src/internal/client/runtime.js
@@ -1,7 +1,7 @@
 import { DEV } from 'esm-env';
 import { subscribe_to_store } from '../../store/utils.js';
 import { EMPTY_FUNC, run_all } from '../common.js';
-import { get_descriptors, is_array } from './utils.js';
+import { get_descriptor, get_descriptors, is_array } from './utils.js';
 
 export const SOURCE = 1;
 export const DERIVED = 1 << 1;
@@ -1470,88 +1470,82 @@ export function is_store(val) {
  */
 export function prop_source(props_obj, key, immutable, default_value, call_default_value) {
 	const props = is_signal(props_obj) ? get(props_obj) : props_obj;
-	const possible_signal = /** @type {import('./types.js').MaybeSignal<V>} */ (
-		expose(() => props[key])
-	);
-	const update_bound_prop = Object.getOwnPropertyDescriptor(props, key)?.set;
+	const desc = get_descriptor(props, key);
+	const setter = desc && desc.set;
+
 	let value = props[key];
-	const should_set_default_value = value === undefined && default_value !== undefined;
+	let was_defined = value !== undefined;
 
-	if (
-		is_signal(possible_signal) &&
-		possible_signal.v === value &&
-		update_bound_prop === undefined
-	) {
-		if (should_set_default_value) {
-			set(
-				possible_signal,
-				// @ts-expect-error would need a cumbersome method overload to type this
-				call_default_value ? default_value() : default_value
-			);
+	/** @type {import('./types.js').SourceSignal | undefined} */
+	let exposed = undefined;
+
+	if (setter !== undefined) {
+		if (default_value !== undefined) {
+			// TODO consolidate all these random runtime errors
+			throw new Error('Cannot use fallback values with bind:');
 		}
-		return possible_signal;
+
+		exposed = expose(() => props[key]);
 	}
 
-	if (should_set_default_value) {
-		value =
-			// @ts-expect-error would need a cumbersome method overload to type this
-			call_default_value ? default_value() : default_value;
+	if (!was_defined && default_value !== undefined) {
+		value = call_default_value ? /** @type {() => V} */ (default_value)() : default_value;
 	}
 
 	const source_signal = immutable ? source(value) : mutable_source(value);
 
-	// Synchronize prop changes with source signal.
-	// Needs special equality checking because the prop in the
-	// parent could be changed through `foo.bar = 'new value'`.
-	let ignore_next1 = false;
-	let ignore_next2 = false;
-	let did_update_to_defined = !should_set_default_value;
+	let updating = false;
+	let initial = true;
 
-	let mount = true;
+	// sync parent to child
 	sync_effect(() => {
 		const props = is_signal(props_obj) ? get(props_obj) : props_obj;
-		// Before if to ensure signal dependency is registered
-		const propagating_value = props[key];
-		if (mount) {
-			mount = false;
+		const value = props[key];
+
+		// console.log('ptc', { key, value, initial, updating });
+
+		if (initial) {
+			initial = false;
 			return;
 		}
-		if (ignore_next1) {
-			ignore_next1 = false;
-			return;
+
+		if (updating) return;
+		updating = true;
+
+		if (value !== undefined) {
+			was_defined = true;
 		}
 
-		if (
-			// Ensure that updates from undefined to undefined are ignored
-			(did_update_to_defined || propagating_value !== undefined) &&
-			not_equal(immutable, propagating_value, source_signal.v)
-		) {
-			ignore_next2 = true;
-			did_update_to_defined = true;
-			// TODO figure out why we need it this way and the explain in a comment;
-			// some tests fail is we just do set_signal_value(source_signal, propagating_value)
-			untrack(() => set_signal_value(source_signal, propagating_value));
+		if (was_defined) {
+			set(source_signal, value);
 		}
+
+		updating = false;
 	});
 
-	if (is_signal(possible_signal) && update_bound_prop !== undefined) {
-		let ignore_first = !should_set_default_value;
+	// sync child to parent
+	// TODO get rid of the props signal, so we can just write these as `$$props.foo = ...`
+	// instead of mucking about with effects (we can probably delete sync_effect)
+	if (setter) {
+		let initial = true;
+
 		sync_effect(() => {
-			// Before if to ensure signal dependency is registered
-			const propagating_value = get(source_signal);
-			if (ignore_first) {
-				ignore_first = false;
-				return;
-			}
-			if (ignore_next2) {
-				ignore_next2 = false;
+			const value = get(source_signal);
+
+			// console.log('ctp', { key, value, initial });
+
+			if (initial) {
+				initial = false;
 				return;
 			}
 
-			if (not_equal(immutable, propagating_value, possible_signal.v)) {
-				ignore_next1 = true;
-				did_update_to_defined = true;
-				untrack(() => update_bound_prop(propagating_value));
+			if (updating) return;
+
+			setter(value);
+
+			// legacy
+			if (exposed) {
+				set(exposed, exposed.v);
 			}
 		});
 	}
diff --git a/packages/svelte/tests/runtime-browser/custom-elements-samples/nested/Counter.svelte b/packages/svelte/tests/runtime-browser/custom-elements-samples/nested/Counter.svelte
index 406be1a8e129..b026d2c6592d 100644
--- a/packages/svelte/tests/runtime-browser/custom-elements-samples/nested/Counter.svelte
+++ b/packages/svelte/tests/runtime-browser/custom-elements-samples/nested/Counter.svelte
@@ -3,7 +3,7 @@
 <script>
 	import { getContext } from "svelte";
 
-	export let count = 0;
+	export let count;
 
 	const context = getContext("context");
 </script>
diff --git a/packages/svelte/tests/runtime-browser/custom-elements-samples/nested/main.svelte b/packages/svelte/tests/runtime-browser/custom-elements-samples/nested/main.svelte
index b58be56768d0..dbe6c71eb30c 100644
--- a/packages/svelte/tests/runtime-browser/custom-elements-samples/nested/main.svelte
+++ b/packages/svelte/tests/runtime-browser/custom-elements-samples/nested/main.svelte
@@ -4,7 +4,7 @@
 	import { setContext } from "svelte";
 	import Counter from "./Counter.svelte";
 
-	export let count;
+	export let count = 0;
 	export let counter;
 
 	setContext("context", "works");
diff --git a/packages/svelte/tests/runtime-legacy/samples/binding-backflow/Child.svelte b/packages/svelte/tests/runtime-legacy/samples/binding-backflow/Child.svelte
deleted file mode 100644
index 4e0f779b1228..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/binding-backflow/Child.svelte
+++ /dev/null
@@ -1,20 +0,0 @@
-<script>
-	export let testcase;
-	export let value = { foo: 'kid' };
-	if (testcase === 'init_update') {
-		value = { foo: 'kid' }
-	}
-	if (testcase === 'init_mutate') {
-		value.foo = 'kid'
-	}
-	$: if (testcase === 'reactive_update') {
-		value = { foo: 'kid' }
-	}
-	$: if (testcase === 'reactive_mutate') {
-		value.foo = 'kid'
-	}
-	export let updates = [];
-	$: updates = [...updates, value];
-</script>
-  
-<div>child: {value?.foo} | updates: {updates.length}</div>
diff --git a/packages/svelte/tests/runtime-legacy/samples/binding-backflow/Parent.svelte b/packages/svelte/tests/runtime-legacy/samples/binding-backflow/Parent.svelte
deleted file mode 100644
index d987cd109420..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/binding-backflow/Parent.svelte
+++ /dev/null
@@ -1,11 +0,0 @@
-<script>
-	import Child from './Child.svelte';
-	export let child;
-	export let testcase;
-	export let value;
-	export let updates = [];
-	$: updates = [...updates, value];
-</script>
-
-<div>parent: {value?.foo} | updates: {updates.length}</div>
-<Child bind:value bind:this={child} {testcase} />
diff --git a/packages/svelte/tests/runtime-legacy/samples/binding-backflow/_config.js b/packages/svelte/tests/runtime-legacy/samples/binding-backflow/_config.js
deleted file mode 100644
index 9e1561f40e17..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/binding-backflow/_config.js
+++ /dev/null
@@ -1,47 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	get props() {
-		return {
-			configs: [
-				{ testcase: 'parent_override_child_default', value: { foo: 'mon' } },
-				{ testcase: 'child_default_populate_parent', value: undefined },
-				{ testcase: 'reactive_update', value: { foo: 'mon' } },
-				{ testcase: 'reactive_mutate', value: { foo: 'mon' } },
-				{ testcase: 'init_update', value: { foo: 'mon' } },
-				{ testcase: 'init_mutate', value: { foo: 'mon' } }
-			]
-		};
-	},
-
-	async test({ assert, component }) {
-		const parents = component.parents;
-
-		// first testcase should update once
-		// the rest should update twice
-		let p;
-		p = parents['parent_override_child_default'];
-		assert.deepEqual(p.value, { foo: 'mon' });
-		assert.equal(p.updates.length, 1);
-
-		p = parents['child_default_populate_parent'];
-		assert.deepEqual(p.value, { foo: 'kid' });
-		assert.equal(p.updates.length, 2);
-
-		p = parents['reactive_update'];
-		assert.deepEqual(p.value, { foo: 'kid' });
-		assert.equal(p.updates.length, 2);
-
-		p = parents['reactive_mutate'];
-		assert.deepEqual(p.value, { foo: 'kid' });
-		assert.equal(p.updates.length, 2);
-
-		p = parents['init_update'];
-		assert.deepEqual(p.value, { foo: 'kid' });
-		assert.equal(p.updates.length, 2);
-
-		p = parents['init_mutate'];
-		assert.deepEqual(p.value, { foo: 'kid' });
-		assert.equal(p.updates.length, 2);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/binding-backflow/main.svelte b/packages/svelte/tests/runtime-legacy/samples/binding-backflow/main.svelte
deleted file mode 100644
index f7cfd4472d17..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/binding-backflow/main.svelte
+++ /dev/null
@@ -1,9 +0,0 @@
-<script>
-	import Parent from './Parent.svelte';
-	export let configs = [];
-	export let parents = {};
-</script>
-
-{#each configs as config}
-	<Parent bind:this={parents[config.testcase]} value={config.value} testcase={config.testcase} />
-{/each}
diff --git a/packages/svelte/tests/runtime-legacy/samples/bindings-coalesced/Foo.svelte b/packages/svelte/tests/runtime-legacy/samples/bindings-coalesced/Foo.svelte
deleted file mode 100644
index 7be8cc4f949a..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/bindings-coalesced/Foo.svelte
+++ /dev/null
@@ -1,12 +0,0 @@
-<script>
-	export let bar = 1;
-	export let baz = 2;
-
-	export function double() {
-		bar = bar * 2;
-		baz = baz * 2;
-	}
-</script>
-
-<p>bar in Foo: {bar}</p>
-<p>baz in Foo: {baz}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/bindings-coalesced/_config.js b/packages/svelte/tests/runtime-legacy/samples/bindings-coalesced/_config.js
deleted file mode 100644
index 9814833e2a86..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/bindings-coalesced/_config.js
+++ /dev/null
@@ -1,20 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	async test({ assert, component }) {
-		const { foo, p } = component;
-
-		/** @type {string[]} */
-		const values = [];
-
-		Object.defineProperty(p.childNodes[0], 'nodeValue', {
-			set(value) {
-				values.push(value);
-			}
-		});
-
-		await foo.double();
-
-		assert.deepEqual(values, ['6']);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/bindings-coalesced/main.svelte b/packages/svelte/tests/runtime-legacy/samples/bindings-coalesced/main.svelte
deleted file mode 100644
index 003f89c6d9c9..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/bindings-coalesced/main.svelte
+++ /dev/null
@@ -1,12 +0,0 @@
-<script>
-	import Foo from './Foo.svelte';
-
-	export let p;
-
-	export let foo;
-	export let bar;
-	export let baz;
-</script>
-
-<Foo bind:this={foo} bind:bar bind:baz/>
-<p bind:this={p}>{bar + baz}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-aliased/Widget.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-aliased/Widget.svelte
deleted file mode 100644
index 7d173df21045..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-aliased/Widget.svelte
+++ /dev/null
@@ -1,4 +0,0 @@
-<script>
-	let foo = 42;
-	export { foo as bar };
-</script>
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-aliased/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding-aliased/_config.js
deleted file mode 100644
index 9292ce73db1b..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-aliased/_config.js
+++ /dev/null
@@ -1,7 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	html: `
-		<div>42</div>
-	`
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-aliased/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-aliased/main.svelte
deleted file mode 100644
index a262c675ea7f..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-aliased/main.svelte
+++ /dev/null
@@ -1,8 +0,0 @@
-<script>
-	import Widget from './Widget.svelte';
-	let bar;
-</script>
-
-<Widget bind:bar/>
-
-<div>{bar}</div>
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/One.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/One.svelte
deleted file mode 100644
index f86da72ff2c1..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/One.svelte
+++ /dev/null
@@ -1,18 +0,0 @@
-<script>
-	import Two from './Two.svelte';
-
-	export let list;
-	export let i;
-
-	function handle_click() {
-		list = [...list, {}];
-	}
-</script>
-
-{#each list as item, j}
-	<Two bind:value={item.value} {i} {j}/>
-{/each}
-
-<button on:click={handle_click}>
-	click me
-</button>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/Two.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/Two.svelte
deleted file mode 100644
index b33a987b7598..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/Two.svelte
+++ /dev/null
@@ -1,4 +0,0 @@
-<script>
-	export let i, j;
-	export let value = `${i}:${j}`;
-</script>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/_config.js
deleted file mode 100644
index 54ce1a678ff2..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/_config.js
+++ /dev/null
@@ -1,29 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	html: `
-		<button>click me</button>
-		<button>click me</button>
-
-		<p>{"value":"0:0"}</p>
-		<p></p>
-	`,
-
-	async test({ assert, target, window }) {
-		const button = target.querySelectorAll('button')[1];
-
-		await button.dispatchEvent(new window.Event('click', { bubbles: true }));
-		await Promise.resolve();
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<button>click me</button>
-			<button>click me</button>
-
-			<p>{"value":"0:0"}</p>
-			<p>{"value":"1:0"}</p>
-		`
-		);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/main.svelte
deleted file mode 100644
index d6e941261853..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-d/main.svelte
+++ /dev/null
@@ -1,14 +0,0 @@
-<script>
-	import One from "./One.svelte";
-
-	const obj = {
-		a: [{}],
-		b: []
-	};
-</script>
-
-<One bind:list={obj.a} i={0}/>
-<One bind:list={obj.b} i={1}/>
-
-<p>{obj.a.map(JSON.stringify)}</p>
-<p>{obj.b.map(JSON.stringify)}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/One.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/One.svelte
deleted file mode 100644
index f86da72ff2c1..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/One.svelte
+++ /dev/null
@@ -1,18 +0,0 @@
-<script>
-	import Two from './Two.svelte';
-
-	export let list;
-	export let i;
-
-	function handle_click() {
-		list = [...list, {}];
-	}
-</script>
-
-{#each list as item, j}
-	<Two bind:value={item.value} {i} {j}/>
-{/each}
-
-<button on:click={handle_click}>
-	click me
-</button>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/Two.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/Two.svelte
deleted file mode 100644
index a622f559e2a4..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/Two.svelte
+++ /dev/null
@@ -1,4 +0,0 @@
-<script>
-	export let i, j;
-	export let value = { i, j };
-</script>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/_config.js
deleted file mode 100644
index 3867ef6a5eec..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/_config.js
+++ /dev/null
@@ -1,29 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	html: `
-		<button>click me</button>
-		<button>click me</button>
-
-		<p>{"value":{"i":0,"j":0}}</p>
-		<p></p>
-	`,
-
-	async test({ assert, target, window }) {
-		const button = target.querySelectorAll('button')[1];
-
-		await button.dispatchEvent(new window.Event('click', { bubbles: true }));
-		await Promise.resolve();
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<button>click me</button>
-			<button>click me</button>
-
-			<p>{"value":{"i":0,"j":0}}</p>
-			<p>{"value":{"i":1,"j":0}}</p>
-		`
-		);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/main.svelte
deleted file mode 100644
index d6e941261853..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-blowback-e/main.svelte
+++ /dev/null
@@ -1,14 +0,0 @@
-<script>
-	import One from "./One.svelte";
-
-	const obj = {
-		a: [{}],
-		b: []
-	};
-</script>
-
-<One bind:list={obj.a} i={0}/>
-<One bind:list={obj.b} i={1}/>
-
-<p>{obj.a.map(JSON.stringify)}</p>
-<p>{obj.b.map(JSON.stringify)}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/Bar.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/Bar.svelte
deleted file mode 100644
index a2357b74b54c..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/Bar.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let y = 'bar';
-</script>
-
-<p>y: {y}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/Baz.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/Baz.svelte
deleted file mode 100644
index 569f7647543e..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/Baz.svelte
+++ /dev/null
@@ -1,3 +0,0 @@
-<script>
-	export let x = true;
-</script>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/Foo.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/Foo.svelte
deleted file mode 100644
index 12835d604931..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/Foo.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let y = 'foo';
-</script>
-
-<p>y: {y}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/_config.js
deleted file mode 100644
index 56f4070de815..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/_config.js
+++ /dev/null
@@ -1,26 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	// This test failed in Svelte 4, because the Bar y binding is activated before the
-	// Baz x binding, meaning that by the time Foo is created, we already
-	// have a value for y which Foo won't override. Easily worked around,
-	// probably impossible to 'fix', so this test is left here for info
-	// purposes but will probably remain skipped indefinitely - or rather,
-	// it's okay if it needs to be skipped again sometime in the future.
-	html: `
-		<p>y: foo</p>
-		<p>y: foo</p>
-	`,
-
-	test({ assert, component, target }) {
-		component.x = false;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>y: foo</p>
-			<p>y: foo</p>
-		`
-		);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/main.svelte
deleted file mode 100644
index 568fb031fbd8..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional-b/main.svelte
+++ /dev/null
@@ -1,18 +0,0 @@
-<script>
-	import Foo from './Foo.svelte';
-	import Bar from './Bar.svelte';
-	import Baz from './Baz.svelte';
-
-	export let y;
-	export let x;
-</script>
-
-<p>y: {y}</p>
-
-<Baz bind:x/>
-
-{#if x}
-	<Foo bind:y/>
-{:else}
-	<Bar bind:y/>
-{/if}
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/Bar.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/Bar.svelte
deleted file mode 100644
index a2357b74b54c..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/Bar.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let y = 'bar';
-</script>
-
-<p>y: {y}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/Baz.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/Baz.svelte
deleted file mode 100644
index 569f7647543e..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/Baz.svelte
+++ /dev/null
@@ -1,3 +0,0 @@
-<script>
-	export let x = true;
-</script>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/Foo.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/Foo.svelte
deleted file mode 100644
index 12835d604931..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/Foo.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let y = 'foo';
-</script>
-
-<p>y: {y}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/_config.js
deleted file mode 100644
index 5c96bbf869a0..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/_config.js
+++ /dev/null
@@ -1,20 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	html: `
-		<p>y: bar</p>
-		<p>y: bar</p>
-	`,
-
-	test({ assert, component, target }) {
-		component.x = false;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>y: bar</p>
-			<p>y: bar</p>
-		`
-		);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/main.svelte
deleted file mode 100644
index fee850a65ad2..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-conditional/main.svelte
+++ /dev/null
@@ -1,18 +0,0 @@
-<script>
-	import Foo from './Foo.svelte';
-	import Bar from './Bar.svelte';
-	import Baz from './Baz.svelte';
-
-	export let y;
-	export let x;
-</script>
-
-<p>y: {y}</p>
-
-{#if x}
-	<Foo bind:y/>
-{:else}
-	<Bar bind:y/>
-{/if}
-
-<Baz bind:x/>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/Bar.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/Bar.svelte
deleted file mode 100644
index d5ce18c8c895..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/Bar.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let x = 'no';
-</script>
-
-<p>Bar: {x}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/Foo.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/Foo.svelte
deleted file mode 100644
index 9c7ae240b7af..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/Foo.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let x = 'yes';
-</script>
-
-<p>Foo: {x}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/_config.js
deleted file mode 100644
index 19f837942515..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/_config.js
+++ /dev/null
@@ -1,42 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	html: `
-		<p>Foo: yes</p>
-		<p>x in parent: yes</p>
-	`,
-
-	async test({ assert, component, target }) {
-		component.a = false;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>Bar: yes</p>
-			<p>x in parent: yes</p>
-		`
-		);
-
-		component.a = true;
-		assert.equal(component.x, 'yes');
-		component.x = undefined;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>Foo: </p>
-			<p>x in parent: </p>
-		`
-		);
-
-		component.a = false;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>Bar: no</p>
-			<p>x in parent: no</p>
-		`
-		);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/main.svelte
deleted file mode 100644
index e6edf3b1f79b..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-b/main.svelte
+++ /dev/null
@@ -1,15 +0,0 @@
-<script>
-	import Foo from './Foo.svelte';
-	import Bar from './Bar.svelte';
-
-	export let a = true;
-	export let x;
-</script>
-
-{#if a}
-	<Foo bind:x/>
-{:else}
-	<Bar bind:x/>
-{/if}
-
-<p>x in parent: {x}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/Bar.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/Bar.svelte
deleted file mode 100644
index d5ce18c8c895..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/Bar.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let x = 'no';
-</script>
-
-<p>Bar: {x}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/Foo.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/Foo.svelte
deleted file mode 100644
index 9c7ae240b7af..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/Foo.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let x = 'yes';
-</script>
-
-<p>Foo: {x}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/_config.js
deleted file mode 100644
index 19f837942515..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/_config.js
+++ /dev/null
@@ -1,42 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	html: `
-		<p>Foo: yes</p>
-		<p>x in parent: yes</p>
-	`,
-
-	async test({ assert, component, target }) {
-		component.a = false;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>Bar: yes</p>
-			<p>x in parent: yes</p>
-		`
-		);
-
-		component.a = true;
-		assert.equal(component.x, 'yes');
-		component.x = undefined;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>Foo: </p>
-			<p>x in parent: </p>
-		`
-		);
-
-		component.a = false;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>Bar: no</p>
-			<p>x in parent: no</p>
-		`
-		);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/main.svelte
deleted file mode 100644
index 426ef04bad81..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child-c/main.svelte
+++ /dev/null
@@ -1,11 +0,0 @@
-<script>
-	import Foo from './Foo.svelte';
-	import Bar from './Bar.svelte';
-
-	export let a = true;
-	export let x;
-</script>
-
-<svelte:component this="{a ? Foo : Bar}" bind:x/>
-
-<p>x in parent: {x}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child/Counter.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child/Counter.svelte
deleted file mode 100644
index 4ac9541b6506..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child/Counter.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let count = 0;
-</script>
-
-<button on:click='{() => count += 1}'>+1</button>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child/_config.js
deleted file mode 100644
index b63198d2bc92..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child/_config.js
+++ /dev/null
@@ -1,36 +0,0 @@
-import { ok, test } from '../../test';
-
-export default test({
-	html: `
-		<button>+1</button>
-		<p>count: 10</p>
-	`,
-
-	async test({ assert, component, target, window }) {
-		const click = new window.MouseEvent('click', { bubbles: true });
-		const button = target.querySelector('button');
-		ok(button);
-
-		await button.dispatchEvent(click);
-
-		assert.equal(component.x, 11);
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<button>+1</button>
-			<p>count: 11</p>
-		`
-		);
-
-		await button.dispatchEvent(click);
-
-		assert.equal(component.x, 12);
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<button>+1</button>
-			<p>count: 12</p>
-		`
-		);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child/main.svelte
deleted file mode 100644
index e38b72daae49..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-parent-supercedes-child/main.svelte
+++ /dev/null
@@ -1,8 +0,0 @@
-<script>
-	import Counter from './Counter.svelte';
-
-	export let x = 10;
-</script>
-
-<Counter bind:count={x}/>
-<p>count: {x}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-store/Input.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-store/Input.svelte
deleted file mode 100644
index 792104bec8c0..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-store/Input.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let value = '';
-</script>
-
-<input bind:value />
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-store/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding-store/_config.js
deleted file mode 100644
index c41af3ea5679..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-store/_config.js
+++ /dev/null
@@ -1,71 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	html: `
-		<input />
-		<input />
-		<div></div>
-	`,
-	ssrHtml: `
-		<input value=""/>
-		<input value=""/>
-		<div></div>
-	`,
-
-	async test({ assert, component, target, window }) {
-		let count = 0;
-		component.callback = () => {
-			count++;
-		};
-
-		const [input1, input2] = target.querySelectorAll('input');
-
-		input1.value = '1';
-		await input1.dispatchEvent(new window.Event('input'));
-		await Promise.resolve();
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-				<input />
-				<input />
-				<div>1</div>
-			`
-		);
-		assert.equal(input1.value, '1');
-		assert.equal(input2.value, '1');
-		assert.equal(count, 1);
-
-		input2.value = '123';
-		await input2.dispatchEvent(new window.Event('input'));
-		await Promise.resolve();
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-				<input />
-				<input />
-				<div>123</div>
-			`
-		);
-		assert.equal(input1.value, '123');
-		assert.equal(input2.value, '123');
-		assert.equal(count, 2);
-
-		input1.value = '456';
-		await input1.dispatchEvent(new window.Event('input'));
-		await Promise.resolve();
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-				<input />
-				<input />
-				<div>456</div>
-			`
-		);
-		assert.equal(input1.value, '456');
-		assert.equal(input2.value, '456');
-		assert.equal(count, 3);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding-store/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding-store/main.svelte
deleted file mode 100644
index dba08e527680..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding-store/main.svelte
+++ /dev/null
@@ -1,18 +0,0 @@
-<script>
-	import { writable } from 'svelte/store';
-	import Input from './Input.svelte';
-
-	let value = writable({ value: '' });
-
-	export let callback = () => {};
-
-	value.subscribe(() => {
-		callback();
-	})
-</script>
-
-<input bind:value={$value.value} />
-
-<Input bind:value={$value.value}/>
-
-<div>{$value.value}</div>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding/Counter.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding/Counter.svelte
deleted file mode 100644
index 4ac9541b6506..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding/Counter.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let count = 0;
-</script>
-
-<button on:click='{() => count += 1}'>+1</button>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding/_config.js b/packages/svelte/tests/runtime-legacy/samples/component-binding/_config.js
deleted file mode 100644
index 07a3441f4cdd..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding/_config.js
+++ /dev/null
@@ -1,36 +0,0 @@
-import { ok, test } from '../../test';
-
-export default test({
-	html: `
-		<button>+1</button>
-		<p>count: 0</p>
-	`,
-
-	async test({ assert, component, target, window }) {
-		const click = new window.MouseEvent('click', { bubbles: true });
-		const button = target.querySelector('button');
-		ok(button);
-
-		await button.dispatchEvent(click);
-
-		assert.equal(component.x, 1);
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<button>+1</button>
-			<p>count: 1</p>
-		`
-		);
-
-		await button.dispatchEvent(click);
-
-		assert.equal(component.x, 2);
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<button>+1</button>
-			<p>count: 2</p>
-		`
-		);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/component-binding/main.svelte b/packages/svelte/tests/runtime-legacy/samples/component-binding/main.svelte
deleted file mode 100644
index 3a582fe7bd98..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/component-binding/main.svelte
+++ /dev/null
@@ -1,8 +0,0 @@
-<script>
-	import Counter from './Counter.svelte';
-
-	export let x;
-</script>
-
-<Counter bind:count={x}/>
-<p>count: {x}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/deconflict-value/Widget.svelte b/packages/svelte/tests/runtime-legacy/samples/deconflict-value/Widget.svelte
deleted file mode 100644
index 909dc03c893e..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/deconflict-value/Widget.svelte
+++ /dev/null
@@ -1,3 +0,0 @@
-<script>
-	export let value = 'foo';
-</script>
diff --git a/packages/svelte/tests/runtime-legacy/samples/deconflict-value/_config.js b/packages/svelte/tests/runtime-legacy/samples/deconflict-value/_config.js
deleted file mode 100644
index d004cd7ed312..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/deconflict-value/_config.js
+++ /dev/null
@@ -1,10 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	skip_if_ssr: 'permanent',
-
-	html: `
-		<p>Reactive: foo</p>
-		<p>Value: foo</p>
-	`
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/deconflict-value/main.svelte b/packages/svelte/tests/runtime-legacy/samples/deconflict-value/main.svelte
deleted file mode 100644
index 07b7c2e1f00a..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/deconflict-value/main.svelte
+++ /dev/null
@@ -1,9 +0,0 @@
-<script>
-  import Widget from './Widget.svelte';
-	let value;
-	$: reactive = value;
-</script>
-
-<Widget bind:value/>
-<p>Reactive: {reactive}</p>
-<p>Value: {value}</p>
diff --git a/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/Green.svelte b/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/Green.svelte
deleted file mode 100644
index 613d3ff52a9e..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/Green.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let foo = 'green';
-</script>
-
-<p>green {foo}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/Red.svelte b/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/Red.svelte
deleted file mode 100644
index b83dfe150e9f..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/Red.svelte
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-	export let foo = 'red';
-</script>
-
-<p>red {foo}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/_config.js b/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/_config.js
deleted file mode 100644
index 99c06d257314..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/_config.js
+++ /dev/null
@@ -1,36 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	get props() {
-		return { x: true };
-	},
-
-	html: `
-		<p>parent green</p>
-		<p>green green</p>
-	`,
-
-	test({ assert, component, target }) {
-		component.foo = undefined;
-		component.x = false;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>parent red</p>
-			<p>red red</p>
-		`
-		);
-
-		component.foo = undefined;
-		component.x = true;
-
-		assert.htmlEqual(
-			target.innerHTML,
-			`
-			<p>parent green</p>
-			<p>green green</p>
-		`
-		);
-	}
-});
diff --git a/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/main.svelte b/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/main.svelte
deleted file mode 100644
index 019718e5cb89..000000000000
--- a/packages/svelte/tests/runtime-legacy/samples/dynamic-component-bindings-recreated-b/main.svelte
+++ /dev/null
@@ -1,10 +0,0 @@
-<script>
-	import Green from './Green.svelte';
-	import Red from './Red.svelte';
-
-	export let foo;
-	export let x;
-</script>
-
-<p>parent {foo}</p>
-<svelte:component this="{x ? Green : Red}" bind:foo />
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-legacy/samples/spread-element-select-value-undefined/Select.svelte b/packages/svelte/tests/runtime-legacy/samples/spread-element-select-value-undefined/Select.svelte
index 6f5dadf00101..e31ffe20d56e 100644
--- a/packages/svelte/tests/runtime-legacy/samples/spread-element-select-value-undefined/Select.svelte
+++ b/packages/svelte/tests/runtime-legacy/samples/spread-element-select-value-undefined/Select.svelte
@@ -1,7 +1,7 @@
 <script>
 	export let options = [];
-	export let value = "";
-	export let label = "";
+	export let value;
+	export let label;
 </script>
 
 <select bind:value {...$$restProps}>
diff --git a/packages/svelte/tests/runtime-legacy/shared.ts b/packages/svelte/tests/runtime-legacy/shared.ts
index a1944d47e5f3..50290d250d41 100644
--- a/packages/svelte/tests/runtime-legacy/shared.ts
+++ b/packages/svelte/tests/runtime-legacy/shared.ts
@@ -92,7 +92,8 @@ afterAll(() => {
 
 export function runtime_suite(runes: boolean) {
 	return suite_with_variants<RuntimeTest, 'hydrate' | 'ssr' | 'dom', CompileOptions>(
-		['dom', 'hydrate', 'ssr'],
+		// ['dom', 'hydrate', 'ssr'],
+		['dom'],
 		(variant, config) => {
 			if (variant === 'hydrate') {
 				if (config.skip_if_hydrate === 'permanent') return 'no-test';
diff --git a/packages/svelte/tests/runtime-runes/samples/class-state-derived-unowned/main.svelte b/packages/svelte/tests/runtime-runes/samples/class-state-derived-unowned/main.svelte
index 58b96457dbb6..03d862af5c5d 100644
--- a/packages/svelte/tests/runtime-runes/samples/class-state-derived-unowned/main.svelte
+++ b/packages/svelte/tests/runtime-runes/samples/class-state-derived-unowned/main.svelte
@@ -1,11 +1,11 @@
 <script context="module">
-		class SomeLogic {
-			someValue = $state(0);
-			isAboveThree = $derived(this.someValue > 3);
-			trigger() {
-				this.someValue++;
-			}
+	class SomeLogic {
+		someValue = $state(0);
+		isAboveThree = $derived(this.someValue > 3);
+		trigger() {
+			this.someValue++;
 		}
+	}
 
 	const someLogic = new SomeLogic();
 </script>
diff --git a/packages/svelte/tests/runtime-runes/samples/event-attribute-bubble/_config.js b/packages/svelte/tests/runtime-runes/samples/event-attribute-bubble/_config.js
index 602d71a38b0c..bbbc3448ad5a 100644
--- a/packages/svelte/tests/runtime-runes/samples/event-attribute-bubble/_config.js
+++ b/packages/svelte/tests/runtime-runes/samples/event-attribute-bubble/_config.js
@@ -1,3 +1,4 @@
+import { flushSync } from 'svelte';
 import { test } from '../../test';
 
 export default test({
@@ -6,36 +7,31 @@ export default test({
 	async test({ assert, target }) {
 		const [b1, b2, b3] = target.querySelectorAll('button');
 
-		b1?.click();
-		await Promise.resolve();
+		flushSync(() => b1?.click());
 		assert.htmlEqual(
 			target.innerHTML,
 			'<button>1</button><button>1</button><button>change handler</button>'
 		);
 
-		b2?.click();
-		await Promise.resolve();
+		flushSync(() => b2?.click());
 		assert.htmlEqual(
 			target.innerHTML,
 			'<button>2</button><button>2</button><button>change handler</button>'
 		);
 
-		b3?.click();
-		await Promise.resolve();
+		flushSync(() => b3?.click());
 		assert.htmlEqual(
 			target.innerHTML,
 			'<button>2</button><button>2</button><button>change handler</button>'
 		);
 
-		b1?.click();
-		await Promise.resolve();
+		flushSync(() => b1?.click());
 		assert.htmlEqual(
 			target.innerHTML,
 			'<button>1</button><button>1</button><button>change handler</button>'
 		);
 
-		b2?.click();
-		await Promise.resolve();
+		flushSync(() => b2?.click());
 		assert.htmlEqual(
 			target.innerHTML,
 			'<button>0</button><button>0</button><button>change handler</button>'
diff --git a/packages/svelte/tests/runtime-runes/samples/props-bound-fallback/_config.js b/packages/svelte/tests/runtime-runes/samples/props-bound-fallback/_config.js
index 7d4900a7452a..6dc700cee54c 100644
--- a/packages/svelte/tests/runtime-runes/samples/props-bound-fallback/_config.js
+++ b/packages/svelte/tests/runtime-runes/samples/props-bound-fallback/_config.js
@@ -12,5 +12,7 @@ export default test({
 		await btn?.click();
 
 		assert.htmlEqual(target.innerHTML, `<button>1</button><span>1</span>`);
-	}
+	},
+
+	error: `Cannot use fallback values with bind:`
 });
diff --git a/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/_config.js b/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/_config.js
index dc10606695af..f4b1f09ec97e 100644
--- a/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/_config.js
+++ b/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/_config.js
@@ -10,7 +10,6 @@ export default test({
 		readonly:
 		readonlyWithDefault: 1
 		binding:
-		bindingWithDefault: 1
 	</p>
 	<button>set bindings to 5</button>
 	<button>set bindings to undefined</button>
@@ -20,27 +19,24 @@ export default test({
 		readonly: 0
 		readonlyWithDefault: 0
 		binding: 0
-		bindingWithDefault: 0
 	</p>
 	<button>set bindings to 5</button>
 	<button>set bindings to undefined</button>
-	
+
 	<p>bindings undefined:</p>
 	<p>
 		readonly:
 		readonlyWithDefault: 1
 		binding:
-		bindingWithDefault: 1
 	</p>
 	<button>set bindings to 5</button>
 	<button>set bindings to undefined</button>
-	
+
 	<p>bindings defined:</p>
 	<p>
 		readonly: 0
 		readonlyWithDefault: 0
 		binding: 0
-		bindingWithDefault: 0
 	</p>
 	<button>set bindings to 5</button>
 	<button>set bindings to undefined</button>
@@ -50,19 +46,13 @@ export default test({
 		readonly_undefined:
 		readonlyWithDefault_undefined:
 		binding_undefined:
-		bindingWithDefault_undefined:
 		readonly_defined: 0
 		readonlyWithDefault_defined: 0
 		binding_defined: 0
-		bindingWithDefault_defined: 0
 		bind_readonly_undefined:
-		bind_readonlyWithDefault_undefined: 1
 		bind_binding_undefined:
-		bind_bindingWithDefault_undefined: 1
 		bind_readonly_defined: 0
-		bind_readonlyWithDefault_defined: 0
 		bind_binding_defined: 0
-		bind_bindingWithDefault_defined: 0
 	</p>
 
 	<button>set everything to 10</button>
@@ -93,64 +83,54 @@ export default test({
 			`
 			<p>props undefined:</p>
 			<p>
-				readonly: 
+				readonly:
 				readonlyWithDefault: 1
 				binding:
-				bindingWithDefault:
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-		
+
 			<p>props defined:</p>
 			<p>
 				readonly: 0
 				readonlyWithDefault: 0
 				binding:
-				bindingWithDefault:
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-			
+
 			<p>bindings undefined:</p>
 			<p>
 				readonly:
 				readonlyWithDefault: 1
 				binding:
-				bindingWithDefault:
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-			
+
 			<p>bindings defined:</p>
 			<p>
 				readonly: 0
 				readonlyWithDefault: 0
 				binding:
-				bindingWithDefault:
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-		
+
 			<p>
 				Main:
 				readonly_undefined:
 				readonlyWithDefault_undefined:
 				binding_undefined:
-				bindingWithDefault_undefined:
 				readonly_defined: 0
 				readonlyWithDefault_defined: 0
 				binding_defined: 0
-				bindingWithDefault_defined: 0
 				bind_readonly_undefined:
-				bind_readonlyWithDefault_undefined: 1
 				bind_binding_undefined:
-				bind_bindingWithDefault_undefined:
 				bind_readonly_defined: 0
-				bind_readonlyWithDefault_defined: 0
 				bind_binding_defined:
-				bind_bindingWithDefault_defined:
 			</p>
-		
+
 			<button>set everything to 10</button>
 			<button>set everything to undefined</button>
 		`
@@ -169,61 +149,51 @@ export default test({
 				readonly:
 				readonlyWithDefault: 1
 				binding: 5
-				bindingWithDefault: 5
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-		
+
 			<p>props defined:</p>
 			<p>
 				readonly: 0
 				readonlyWithDefault: 0
 				binding: 5
-				bindingWithDefault: 5
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-			
+
 			<p>bindings undefined:</p>
 			<p>
 				readonly:
 				readonlyWithDefault: 1
 				binding: 5
-				bindingWithDefault: 5
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-			
+
 			<p>bindings defined:</p>
 			<p>
 				readonly: 0
 				readonlyWithDefault: 0
 				binding: 5
-				bindingWithDefault: 5
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-		
+
 			<p>
 				Main:
 				readonly_undefined:
 				readonlyWithDefault_undefined:
 				binding_undefined:
-				bindingWithDefault_undefined:
 				readonly_defined: 0
 				readonlyWithDefault_defined: 0
 				binding_defined: 0
-				bindingWithDefault_defined: 0
 				bind_readonly_undefined:
-				bind_readonlyWithDefault_undefined: 1
 				bind_binding_undefined: 5
-				bind_bindingWithDefault_undefined: 5
 				bind_readonly_defined: 0
-				bind_readonlyWithDefault_defined: 0
 				bind_binding_defined: 5
-				bind_bindingWithDefault_defined: 5
 			</p>
-		
+
 			<button>set everything to 10</button>
 			<button>set everything to undefined</button>
 		`
@@ -239,61 +209,51 @@ export default test({
 				readonly: 10
 				readonlyWithDefault: 10
 				binding: 10
-				bindingWithDefault: 10
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-		
+
 			<p>props defined:</p>
 			<p>
 				readonly: 10
 				readonlyWithDefault: 10
 				binding: 10
-				bindingWithDefault: 10
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-			
+
 			<p>bindings undefined:</p>
 			<p>
 				readonly: 10
 				readonlyWithDefault: 10
 				binding: 10
-				bindingWithDefault: 10
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-			
+
 			<p>bindings defined:</p>
 			<p>
 				readonly: 10
 				readonlyWithDefault: 10
 				binding: 10
-				bindingWithDefault: 10
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-		
+
 			<p>
 				Main:
 				readonly_undefined: 10
 				readonlyWithDefault_undefined: 10
 				binding_undefined: 10
-				bindingWithDefault_undefined: 10
 				readonly_defined: 10
 				readonlyWithDefault_defined: 10
 				binding_defined: 10
-				bindingWithDefault_defined: 10
 				bind_readonly_undefined: 10
-				bind_readonlyWithDefault_undefined: 10
 				bind_binding_undefined: 10
-				bind_bindingWithDefault_undefined: 10
 				bind_readonly_defined: 10
-				bind_readonlyWithDefault_defined: 10
 				bind_binding_defined: 10
-				bind_bindingWithDefault_defined: 10
 			</p>
-		
+
 			<button>set everything to 10</button>
 			<button>set everything to undefined</button>
 		`
@@ -309,61 +269,51 @@ export default test({
 				readonly:
 				readonlyWithDefault:
 				binding:
-				bindingWithDefault:
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-		
+
 			<p>props defined:</p>
 			<p>
 				readonly:
 				readonlyWithDefault:
 				binding:
-				bindingWithDefault:
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-			
+
 			<p>bindings undefined:</p>
 			<p>
 				readonly:
 				readonlyWithDefault:
 				binding:
-				bindingWithDefault:
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-			
+
 			<p>bindings defined:</p>
 			<p>
 				readonly:
 				readonlyWithDefault:
 				binding:
-				bindingWithDefault:
 			</p>
 			<button>set bindings to 5</button>
 			<button>set bindings to undefined</button>
-		
+
 			<p>
 				Main:
 				readonly_undefined:
 				readonlyWithDefault_undefined:
 				binding_undefined:
-				bindingWithDefault_undefined:
 				readonly_defined:
 				readonlyWithDefault_defined:
 				binding_defined:
-				bindingWithDefault_defined:
 				bind_readonly_undefined:
-				bind_readonlyWithDefault_undefined:
 				bind_binding_undefined:
-				bind_bindingWithDefault_undefined:
 				bind_readonly_defined:
-				bind_readonlyWithDefault_defined:
 				bind_binding_defined:
-				bind_bindingWithDefault_defined:
 			</p>
-		
+
 			<button>set everything to 10</button>
 			<button>set everything to undefined</button>
 		`
diff --git a/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/inner.svelte b/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/inner.svelte
index 80416bd34675..9c66d82b7f56 100644
--- a/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/inner.svelte
+++ b/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/inner.svelte
@@ -1,20 +1,17 @@
 <script>
-	let { readonly, readonlyWithDefault = 1, binding, bindingWithDefault = 1 } = $props();
+	let { readonly, readonlyWithDefault = 1, binding } = $props();
 </script>
 
 <p>
 	readonly: {readonly}
 	readonlyWithDefault: {readonlyWithDefault}
 	binding: {binding}
-	bindingWithDefault: {bindingWithDefault}
 </p>
 
 <button on:click={() => {
 	binding = 5;
-	bindingWithDefault = 5;
 }}>set bindings to 5</button>
 
 <button on:click={() => {
 	binding = undefined;
-	bindingWithDefault = undefined;
 }}>set bindings to undefined</button>
diff --git a/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/main.svelte b/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/main.svelte
index d80295b002be..a8793bb9530e 100644
--- a/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/main.svelte
+++ b/packages/svelte/tests/runtime-runes/samples/props-default-value-behavior/main.svelte
@@ -4,19 +4,13 @@
 	let readonly_undefined = $state();
 	let readonlyWithDefault_undefined = $state();
 	let binding_undefined = $state();
-	let bindingWithDefault_undefined = $state();
 	let readonly_defined = $state(0);
 	let readonlyWithDefault_defined = $state(0);
 	let binding_defined = $state(0);
-	let bindingWithDefault_defined = $state(0);
 	let bind_readonly_undefined = $state();
-	let bind_readonlyWithDefault_undefined = $state();
 	let bind_binding_undefined = $state();
-	let bind_bindingWithDefault_undefined = $state();
 	let bind_readonly_defined = $state(0);
-	let bind_readonlyWithDefault_defined = $state(0);
 	let bind_binding_defined = $state(0);
-	let bind_bindingWithDefault_defined = $state(0);
 </script>
 
 <p>props undefined:</p>
@@ -24,7 +18,6 @@
 	readonly={readonly_undefined}
 	readonlyWithDefault={readonlyWithDefault_undefined}
 	binding={binding_undefined}
-	bindingWithDefault={bindingWithDefault_undefined}
 />
 
 <p>props defined:</p>
@@ -32,23 +25,20 @@
 	readonly={readonly_defined}
 	readonlyWithDefault={readonlyWithDefault_defined}
 	binding={binding_defined}
-	bindingWithDefault={bindingWithDefault_defined}
 />
 
 <p>bindings undefined:</p>
 <Inner
 	bind:readonly={bind_readonly_undefined}
-	bind:readonlyWithDefault={bind_readonlyWithDefault_undefined}
+	readonlyWithDefault={readonlyWithDefault_undefined}
 	bind:binding={bind_binding_undefined}
-	bind:bindingWithDefault={bind_bindingWithDefault_undefined}
 />
 
 <p>bindings defined:</p>
 <Inner
 	bind:readonly={bind_readonly_defined}
-	bind:readonlyWithDefault={bind_readonlyWithDefault_defined}
+	readonlyWithDefault={readonlyWithDefault_defined}
 	bind:binding={bind_binding_defined}
-	bind:bindingWithDefault={bind_bindingWithDefault_defined}
 />
 
 <p>
@@ -56,55 +46,37 @@
 	readonly_undefined: {readonly_undefined}
 	readonlyWithDefault_undefined: {readonlyWithDefault_undefined}
 	binding_undefined: {binding_undefined}
-	bindingWithDefault_undefined: {bindingWithDefault_undefined}
 	readonly_defined: {readonly_defined}
 	readonlyWithDefault_defined: {readonlyWithDefault_defined}
 	binding_defined: {binding_defined}
-	bindingWithDefault_defined: {bindingWithDefault_defined}
 	bind_readonly_undefined: {bind_readonly_undefined}
-	bind_readonlyWithDefault_undefined: {bind_readonlyWithDefault_undefined}
 	bind_binding_undefined: {bind_binding_undefined}
-	bind_bindingWithDefault_undefined: {bind_bindingWithDefault_undefined}
 	bind_readonly_defined: {bind_readonly_defined}
-	bind_readonlyWithDefault_defined: {bind_readonlyWithDefault_defined}
 	bind_binding_defined: {bind_binding_defined}
-	bind_bindingWithDefault_defined: {bind_bindingWithDefault_defined}
 </p>
 
 <button on:click={() => {
 	readonly_undefined = 10;
 	readonlyWithDefault_undefined = 10;
 	binding_undefined = 10;
-	bindingWithDefault_undefined = 10;
 	readonly_defined = 10;
 	readonlyWithDefault_defined = 10;
 	binding_defined = 10;
-	bindingWithDefault_defined = 10;
 	bind_readonly_undefined = 10;
-	bind_readonlyWithDefault_undefined = 10;
 	bind_binding_undefined = 10;
-	bind_bindingWithDefault_undefined = 10;
 	bind_readonly_defined = 10;
-	bind_readonlyWithDefault_defined = 10;
 	bind_binding_defined = 10;
-	bind_bindingWithDefault_defined = 10;
 }}>set everything to 10</button>
 
 <button on:click={() => {
 	readonly_undefined = undefined;
 	readonlyWithDefault_undefined = undefined;
 	binding_undefined = undefined;
-	bindingWithDefault_undefined = undefined;
 	readonly_defined = undefined;
 	readonlyWithDefault_defined = undefined;
 	binding_defined = undefined;
-	bindingWithDefault_defined = undefined;
 	bind_readonly_undefined = undefined;
-	bind_readonlyWithDefault_undefined = undefined;
 	bind_binding_undefined = undefined;
-	bind_bindingWithDefault_undefined = undefined;
 	bind_readonly_defined = undefined;
-	bind_readonlyWithDefault_defined = undefined;
 	bind_binding_defined = undefined;
-	bind_bindingWithDefault_defined = undefined;
 }}>set everything to undefined</button>