diff --git a/src/runtime/ambient.ts b/src/runtime/ambient.ts
new file mode 100644
index 0000000000..b094056c59
--- /dev/null
+++ b/src/runtime/ambient.ts
@@ -0,0 +1,19 @@
+declare module '*.svelte' {
+	type Props = Record<string, any>;
+
+	export default class {
+		constructor(options: {
+			target: Element;
+			anchor?: Element;
+			props?: Props;
+			hydrate?: boolean;
+			intro?: boolean;
+		});
+
+		$set(props: Props): void;
+		$on<T = any>(event: string, callback: (event: CustomEvent<T>) => void): () => void;
+		$destroy(): void;
+
+		[accessor: string]: any;
+	}
+}
diff --git a/src/runtime/index.ts b/src/runtime/index.ts
index 40928da8a0..0973b93f1e 100644
--- a/src/runtime/index.ts
+++ b/src/runtime/index.ts
@@ -1,3 +1,5 @@
+import './ambient';
+
 export {
 	onMount,
 	onDestroy,