diff --git a/.changeset/rare-berries-retire.md b/.changeset/rare-berries-retire.md
new file mode 100644
index 000000000000..0017a576bbfa
--- /dev/null
+++ b/.changeset/rare-berries-retire.md
@@ -0,0 +1,6 @@
+---
+'@sveltejs/adapter-cloudflare-workers': patch
+'@sveltejs/adapter-cloudflare': patch
+---
+
+fix: prevent Vitest from hanging, which was not fully addressed in [#12830](https://github.com/sveltejs/kit/pull/12830)
diff --git a/packages/adapter-cloudflare-workers/index.js b/packages/adapter-cloudflare-workers/index.js
index be1d98245cbd..5da3fe275022 100644
--- a/packages/adapter-cloudflare-workers/index.js
+++ b/packages/adapter-cloudflare-workers/index.js
@@ -152,7 +152,7 @@ export default function ({ config = 'wrangler.toml', platformProxy = {} } = {})
 		emulate() {
 			// we want to invoke `getPlatformProxy` only once, but await it only when it is accessed.
 			// If we would await it here, it would hang indefinitely because the platform proxy only resolves once a request happens
-			const getting_platform = (async () => {
+			const get_emulated = async () => {
 				const proxy = await getPlatformProxy(platformProxy);
 				const platform = /** @type {App.Platform} */ ({
 					env: proxy.env,
@@ -160,11 +160,9 @@ export default function ({ config = 'wrangler.toml', platformProxy = {} } = {})
 					caches: proxy.caches,
 					cf: proxy.cf
 				});
-
 				/** @type {Record<string, any>} */
 				const env = {};
 				const prerender_platform = /** @type {App.Platform} */ (/** @type {unknown} */ ({ env }));
-
 				for (const key in proxy.env) {
 					Object.defineProperty(env, key, {
 						get: () => {
@@ -173,12 +171,15 @@ export default function ({ config = 'wrangler.toml', platformProxy = {} } = {})
 					});
 				}
 				return { platform, prerender_platform };
-			})();
+			};
+
+			/** @type {{ platform: App.Platform, prerender_platform: App.Platform }} */
+			let emulated;
 
 			return {
 				platform: async ({ prerender }) => {
-					const { platform, prerender_platform } = await getting_platform;
-					return prerender ? prerender_platform : platform;
+					emulated ??= await get_emulated();
+					return prerender ? emulated.prerender_platform : emulated.platform;
 				}
 			};
 		}
diff --git a/packages/adapter-cloudflare/index.js b/packages/adapter-cloudflare/index.js
index fa47122abe29..e00eb9889929 100644
--- a/packages/adapter-cloudflare/index.js
+++ b/packages/adapter-cloudflare/index.js
@@ -70,7 +70,7 @@ export default function (options = {}) {
 		emulate() {
 			// we want to invoke `getPlatformProxy` only once, but await it only when it is accessed.
 			// If we would await it here, it would hang indefinitely because the platform proxy only resolves once a request happens
-			const getting_platform = (async () => {
+			const get_emulated = async () => {
 				const proxy = await getPlatformProxy(options.platformProxy);
 				const platform = /** @type {App.Platform} */ ({
 					env: proxy.env,
@@ -78,11 +78,9 @@ export default function (options = {}) {
 					caches: proxy.caches,
 					cf: proxy.cf
 				});
-
 				/** @type {Record<string, any>} */
 				const env = {};
 				const prerender_platform = /** @type {App.Platform} */ (/** @type {unknown} */ ({ env }));
-
 				for (const key in proxy.env) {
 					Object.defineProperty(env, key, {
 						get: () => {
@@ -91,12 +89,15 @@ export default function (options = {}) {
 					});
 				}
 				return { platform, prerender_platform };
-			})();
+			};
+
+			/** @type {{ platform: App.Platform, prerender_platform: App.Platform }} */
+			let emulated;
 
 			return {
 				platform: async ({ prerender }) => {
-					const { platform, prerender_platform } = await getting_platform;
-					return prerender ? prerender_platform : platform;
+					emulated ??= await get_emulated();
+					return prerender ? emulated.prerender_platform : emulated.platform;
 				}
 			};
 		}