Refactor prerendering chunk handling (#11245)

33 files changed, 692 insertions, 193 deletions

diff --git a/.changeset/three-boxes-sniff.md b/.changeset/three-boxes-sniff.md
new file mode 100644
index 000000000..50b99c08d
--- /dev/null
+++ b/.changeset/three-boxes-sniff.md
@@ -0,0 +1,5 @@
+---
+"astro": patch
+---
+
+Refactors prerendering chunk handling to correctly remove unused code during the SSR runtime
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 918fffaca..2f2e63786 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -176,6 +176,12 @@ Any tests for `astro build` output should use the main `mocha` tests rather than
 
 If a test needs to validate what happens on the page after it's loading in the browser, that's a perfect use for E2E dev server tests, i.e. to verify that hot-module reloading works in `astro dev` or that components were client hydrated and are interactive.
 
+#### Creating tests
+
+When creating new tests, it's best to reference other existing test files and replicate the same setup. Some other tips include:
+
+- When re-using a fixture multiple times with different configurations, you should also configure unique `outDir`, `build.client`, and `build.server` values so the build output runtime isn't cached and shared by ESM between test runs.
+
 ### Other useful commands
 
 ```shell
diff --git a/packages/astro/src/core/build/internal.ts b/packages/astro/src/core/build/internal.ts
index 615d36640..07ecf261d 100644
--- a/packages/astro/src/core/build/internal.ts
+++ b/packages/astro/src/core/build/internal.ts
@@ -113,6 +113,11 @@ export interface BuildInternals {
 	ssrSplitEntryChunks: Map<string, Rollup.OutputChunk>;
 	componentMetadata: SSRResult['componentMetadata'];
 	middlewareEntryPoint?: URL;
+
+	/**
+	 * Chunks in the bundle that are only used in prerendering that we can delete later
+	 */
+	prerenderOnlyChunks: Rollup.OutputChunk[];
 }
 
 /**
@@ -151,6 +156,7 @@ export function createBuildInternals(): BuildInternals {
 		ssrSplitEntryChunks: new Map(),
 		entryPoints: new Map(),
 		cacheManifestUsed: false,
+		prerenderOnlyChunks: [],
 	};
 }
 
diff --git a/packages/astro/src/core/build/page-data.ts b/packages/astro/src/core/build/page-data.ts
index 6358a6f55..c4c1e180c 100644
--- a/packages/astro/src/core/build/page-data.ts
+++ b/packages/astro/src/core/build/page-data.ts
@@ -57,7 +57,6 @@ export async function collectPagesData(
 				moduleSpecifier: '',
 				styles: [],
 				hoistedScript: undefined,
-				hasSharedModules: false,
 			};
 
 			clearInterval(routeCollectionLogTimeout);
@@ -80,7 +79,6 @@ export async function collectPagesData(
 			moduleSpecifier: '',
 			styles: [],
 			hoistedScript: undefined,
-			hasSharedModules: false,
 		};
 	}
 
diff --git a/packages/astro/src/core/build/plugins/plugin-chunks.ts b/packages/astro/src/core/build/plugins/plugin-chunks.ts
index 30b3e4938..bcd1d15bf 100644
--- a/packages/astro/src/core/build/plugins/plugin-chunks.ts
+++ b/packages/astro/src/core/build/plugins/plugin-chunks.ts
@@ -12,6 +12,15 @@ export function vitePluginChunks(): VitePlugin {
 					if (id.includes('astro/dist/runtime/server/')) {
 						return 'astro/server';
 					}
+					// Split the Astro runtime into a separate chunk for readability
+					if (id.includes('astro/dist/runtime')) {
+						return 'astro';
+					}
+					// Place `astro/env/setup` import in its own chunk to prevent Rollup's TLA bug
+					// https://github.com/rollup/rollup/issues/4708
+					if (id.includes('astro/dist/env/setup')) {
+						return 'astro/env-setup';
+					}
 				},
 			});
 		},
diff --git a/packages/astro/src/core/build/plugins/plugin-prerender.ts b/packages/astro/src/core/build/plugins/plugin-prerender.ts
index 171d998b7..b7feb70e3 100644
--- a/packages/astro/src/core/build/plugins/plugin-prerender.ts
+++ b/packages/astro/src/core/build/plugins/plugin-prerender.ts
@@ -1,87 +1,105 @@
-import path from 'node:path';
-import type { Plugin as VitePlugin } from 'vite';
+import type { Rollup, Plugin as VitePlugin } from 'vite';
 import { getPrerenderMetadata } from '../../../prerender/metadata.js';
 import type { BuildInternals } from '../internal.js';
 import type { AstroBuildPlugin } from '../plugin.js';
 import type { StaticBuildOptions } from '../types.js';
-import { extendManualChunks } from './util.js';
+import { ASTRO_PAGE_RESOLVED_MODULE_ID } from './plugin-pages.js';
+import { getPagesFromVirtualModulePageName } from './util.js';
 
-function vitePluginPrerender(opts: StaticBuildOptions, internals: BuildInternals): VitePlugin {
+function vitePluginPrerender(internals: BuildInternals): VitePlugin {
 	return {
 		name: 'astro:rollup-plugin-prerender',
 
-		outputOptions(outputOptions) {
-			extendManualChunks(outputOptions, {
-				after(id, meta) {
-					// Split the Astro runtime into a separate chunk for readability
-					if (id.includes('astro/dist/runtime')) {
-						return 'astro';
-					}
-					const pageInfo = internals.pagesByViteID.get(id);
-					let hasSharedModules = false;
-					if (pageInfo) {
-						// prerendered pages should be split into their own chunk
-						// Important: this can't be in the `pages/` directory!
-						if (getPrerenderMetadata(meta.getModuleInfo(id)!)) {
-							const infoMeta = meta.getModuleInfo(id)!;
+		generateBundle(_, bundle) {
+			const moduleIds = this.getModuleIds();
+			for (const id of moduleIds) {
+				const pageInfo = internals.pagesByViteID.get(id);
+				if (!pageInfo) continue;
+				const moduleInfo = this.getModuleInfo(id);
+				if (!moduleInfo) continue;
 
-							// Here, we check if this page is importing modules that are shared among other modules e.g. middleware, other SSR pages, etc.
-							// we loop the modules that the current page imports
-							for (const moduleId of infoMeta.importedIds) {
-								// we retrieve the metadata of the module
-								const moduleMeta = meta.getModuleInfo(moduleId)!;
-								if (
-									// a shared modules should be inside the `src/` folder, at least
-									moduleMeta.id.startsWith(opts.settings.config.srcDir.pathname) &&
-									// and has at least two importers: the current page and something else
-									moduleMeta.importers.length > 1
-								) {
-									// Now, we have to trace back the modules imported and analyze them;
-									// understanding if a module is eventually shared between two pages isn't easy, because a module could
-									// be imported by a page and a component that is eventually imported by a page.
-									//
-									// Given the previous statement, we only check if
-									// - the module is a page, and it's not pre-rendered
-									// - the module is the middleware
-									// If one of these conditions is met, we need a separate chunk
-									for (const importer of moduleMeta.importedIds) {
-										// we don't want to analyze the same module again, so we skip it
-										if (importer !== id) {
-											const importerModuleMeta = meta.getModuleInfo(importer);
-											if (importerModuleMeta) {
-												// if the module is inside the pages
-												if (importerModuleMeta.id.includes('/pages')) {
-													// we check if it's not pre-rendered
-													if (getPrerenderMetadata(importerModuleMeta) === false) {
-														hasSharedModules = true;
-														break;
-													}
-												}
-												// module isn't an Astro route/page, it could be a middleware
-												else if (importerModuleMeta.id.includes('/middleware')) {
-													hasSharedModules = true;
-													break;
-												}
-											}
-										}
-									}
-								}
-							}
+				const prerender = !!getPrerenderMetadata(moduleInfo);
+				pageInfo.route.prerender = prerender;
+			}
 
-							pageInfo.hasSharedModules = hasSharedModules;
-							pageInfo.route.prerender = true;
-							return 'prerender';
-						}
-						pageInfo.route.prerender = false;
-						// dynamic pages should all go in their own chunk in the pages/* directory
-						return `pages/${path.basename(pageInfo.component)}`;
-					}
-				},
-			});
+			// Find all chunks used in the SSR runtime (that aren't used for prerendering only), then use
+			// the Set to find the inverse, where chunks that are only used for prerendering. It's faster
+			// to compute `internals.prerenderOnlyChunks` this way. The prerendered chunks will be deleted
+			// after we finish prerendering.
+			const nonPrerenderOnlyChunks = getNonPrerenderOnlyChunks(bundle, internals);
+			internals.prerenderOnlyChunks = Object.values(bundle).filter((chunk) => {
+				return chunk.type === 'chunk' && !nonPrerenderOnlyChunks.has(chunk);
+			}) as Rollup.OutputChunk[];
 		},
 	};
 }
 
+function getNonPrerenderOnlyChunks(bundle: Rollup.OutputBundle, internals: BuildInternals) {
+	const chunks = Object.values(bundle);
+
+	const prerenderOnlyEntryChunks = new Set<Rollup.OutputChunk>();
+	const nonPrerenderOnlyEntryChunks = new Set<Rollup.OutputChunk>();
+	for (const chunk of chunks) {
+		if (chunk.type === 'chunk' && (chunk.isEntry || chunk.isDynamicEntry)) {
+			// See if this entry chunk is prerendered, if so, skip it
+			if (chunk.facadeModuleId?.startsWith(ASTRO_PAGE_RESOLVED_MODULE_ID)) {
+				const pageDatas = getPagesFromVirtualModulePageName(
+					internals,
+					ASTRO_PAGE_RESOLVED_MODULE_ID,
+					chunk.facadeModuleId
+				);
+				const prerender = pageDatas.every((pageData) => pageData.route.prerender);
+				if (prerender) {
+					prerenderOnlyEntryChunks.add(chunk);
+					continue;
+				}
+			}
+			// Ideally we should record entries when `functionPerRoute` is enabled, but this breaks some tests
+			// that expect the entrypoint to still exist even if it should be unused.
+			// TODO: Revisit this so we can delete additional unused chunks
+			// else if (chunk.facadeModuleId?.startsWith(RESOLVED_SPLIT_MODULE_ID)) {
+			// 	const pageDatas = getPagesFromVirtualModulePageName(
+			// 		internals,
+			// 		RESOLVED_SPLIT_MODULE_ID,
+			// 		chunk.facadeModuleId
+			// 	);
+			// 	const prerender = pageDatas.every((pageData) => pageData.route.prerender);
+			// 	if (prerender) {
+			// 		prerenderOnlyEntryChunks.add(chunk);
+			// 		continue;
+			// 	}
+			// }
+
+			nonPrerenderOnlyEntryChunks.add(chunk);
+		}
+	}
+
+	// From the `nonPrerenderedEntryChunks`, we crawl all the imports/dynamicImports to find all
+	// other chunks that are use by the non-prerendered runtime
+	const nonPrerenderOnlyChunks = new Set(nonPrerenderOnlyEntryChunks);
+	for (const chunk of nonPrerenderOnlyChunks) {
+		for (const importFileName of chunk.imports) {
+			const importChunk = bundle[importFileName];
+			if (importChunk?.type === 'chunk') {
+				nonPrerenderOnlyChunks.add(importChunk);
+			}
+		}
+		for (const dynamicImportFileName of chunk.dynamicImports) {
+			const dynamicImportChunk = bundle[dynamicImportFileName];
+			// The main server entry (entry.mjs) may import a prerender-only entry chunk, we skip in this case
+			// to prevent incorrectly marking it as non-prerendered.
+			if (
+				dynamicImportChunk?.type === 'chunk' &&
+				!prerenderOnlyEntryChunks.has(dynamicImportChunk)
+			) {
+				nonPrerenderOnlyChunks.add(dynamicImportChunk);
+			}
+		}
+	}
+
+	return nonPrerenderOnlyChunks;
+}
+
 export function pluginPrerender(
 	opts: StaticBuildOptions,
 	internals: BuildInternals
@@ -96,7 +114,7 @@ export function pluginPrerender(
 		hooks: {
 			'build:before': () => {
 				return {
-					vitePlugin: vitePluginPrerender(opts, internals),
+					vitePlugin: vitePluginPrerender(internals),
 				};
 			},
 		},
diff --git a/packages/astro/src/core/build/plugins/plugin-ssr.ts b/packages/astro/src/core/build/plugins/plugin-ssr.ts
index 0a10110cd..880a4d6a8 100644
--- a/packages/astro/src/core/build/plugins/plugin-ssr.ts
+++ b/packages/astro/src/core/build/plugins/plugin-ssr.ts
@@ -27,7 +27,17 @@ function vitePluginSSR(
 		name: '@astrojs/vite-plugin-astro-ssr-server',
 		enforce: 'post',
 		options(opts) {
-			return addRollupInput(opts, [SSR_VIRTUAL_MODULE_ID]);
+			const inputs = new Set<string>();
+
+			for (const pageData of Object.values(options.allPages)) {
+				if (routeIsRedirect(pageData.route)) {
+					continue;
+				}
+				inputs.add(getVirtualModulePageName(ASTRO_PAGE_MODULE_ID, pageData.component));
+			}
+
+			inputs.add(SSR_VIRTUAL_MODULE_ID);
+			return addRollupInput(opts, Array.from(inputs));
 		},
 		resolveId(id) {
 			if (id === SSR_VIRTUAL_MODULE_ID) {
@@ -72,7 +82,6 @@ function vitePluginSSR(
 				contents.push(...ssrCode.contents);
 				return [...imports, ...contents, ...exports].join('\n');
 			}
-			return void 0;
 		},
 		async generateBundle(_opts, bundle) {
 			// Add assets from this SSR chunk as well.
@@ -141,23 +150,20 @@ function vitePluginSSRSplit(
 	adapter: AstroAdapter,
 	options: StaticBuildOptions
 ): VitePlugin {
-	const functionPerRouteEnabled = isFunctionPerRouteEnabled(options.settings.adapter);
 	return {
 		name: '@astrojs/vite-plugin-astro-ssr-split',
 		enforce: 'post',
 		options(opts) {
-			if (functionPerRouteEnabled) {
-				const inputs = new Set<string>();
+			const inputs = new Set<string>();
 
-				for (const pageData of Object.values(options.allPages)) {
-					if (routeIsRedirect(pageData.route)) {
-						continue;
-					}
-					inputs.add(getVirtualModulePageName(SPLIT_MODULE_ID, pageData.component));
+			for (const pageData of Object.values(options.allPages)) {
+				if (routeIsRedirect(pageData.route)) {
+					continue;
 				}
-
-				return addRollupInput(opts, Array.from(inputs));
+				inputs.add(getVirtualModulePageName(SPLIT_MODULE_ID, pageData.component));
 			}
+
+			return addRollupInput(opts, Array.from(inputs));
 		},
 		resolveId(id) {
 			if (id.startsWith(SPLIT_MODULE_ID)) {
@@ -185,7 +191,6 @@ function vitePluginSSRSplit(
 
 				return [...imports, ...contents, ...exports].join('\n');
 			}
-			return void 0;
 		},
 		async generateBundle(_opts, bundle) {
 			// Add assets from this SSR chunk as well.
diff --git a/packages/astro/src/core/build/static-build.ts b/packages/astro/src/core/build/static-build.ts
index 73f3a19c5..5b75dbc93 100644
--- a/packages/astro/src/core/build/static-build.ts
+++ b/packages/astro/src/core/build/static-build.ts
@@ -2,7 +2,6 @@ import fs from 'node:fs';
 import path, { extname } from 'node:path';
 import { fileURLToPath, pathToFileURL } from 'node:url';
 import { teardown } from '@astrojs/compiler';
-import * as eslexer from 'es-module-lexer';
 import glob from 'fast-glob';
 import { bgGreen, bgMagenta, black, green } from 'kleur/colors';
 import * as vite from 'vite';
@@ -156,7 +155,7 @@ export async function staticBuild(
 		case isServerLikeOutput(settings.config): {
 			settings.timer.start('Server generate');
 			await generatePages(opts, internals);
-			await cleanStaticOutput(opts, internals, ssrOutputChunkNames);
+			await cleanStaticOutput(opts, internals);
 			opts.logger.info(null, `\n${bgMagenta(black(' finalizing server assets '))}\n`);
 			await ssrMoveAssets(opts);
 			settings.timer.end('Server generate');
@@ -199,6 +198,8 @@ async function ssrBuild(
 			copyPublicDir: !ssr,
 			rollupOptions: {
 				...viteConfig.build?.rollupOptions,
+				// Setting as `exports-only` allows us to safely delete inputs that are only used during prerendering
+				preserveEntrySignatures: 'exports-only',
 				input: [],
 				output: {
 					hoistTransitiveImports: isContentCache,
@@ -381,65 +382,35 @@ async function runPostBuildHooks(
 }
 
 /**
- * For each statically prerendered page, replace their SSR file with a noop.
- * This allows us to run the SSR build only once, but still remove dependencies for statically rendered routes.
- * If a component is shared between a statically rendered route and a SSR route, it will still be included in the SSR build.
+ * Remove chunks that are used for prerendering only
  */
-async function cleanStaticOutput(
-	opts: StaticBuildOptions,
-	internals: BuildInternals,
-	ssrOutputChunkNames: string[]
-) {
-	const prerenderedFiles = new Set();
-	const onDemandsFiles = new Set();
-	for (const pageData of internals.pagesByKeys.values()) {
-		const { moduleSpecifier } = pageData;
-		const bundleId =
-			internals.pageToBundleMap.get(moduleSpecifier) ??
-			internals.entrySpecifierToBundleMap.get(moduleSpecifier);
-		if (pageData.route.prerender && !pageData.hasSharedModules && !onDemandsFiles.has(bundleId)) {
-			prerenderedFiles.add(bundleId);
-		} else {
-			onDemandsFiles.add(bundleId);
-			// Check if the component was not previously added to the static build by a statically rendered route
-			if (prerenderedFiles.has(bundleId)) {
-				prerenderedFiles.delete(bundleId);
-			}
-		}
-	}
+async function cleanStaticOutput(opts: StaticBuildOptions, internals: BuildInternals) {
 	const ssr = isServerLikeOutput(opts.settings.config);
 	const out = ssr
 		? opts.settings.config.build.server
 		: getOutDirWithinCwd(opts.settings.config.outDir);
-	// The SSR output chunks for Astro are all .mjs files
-	const files = ssrOutputChunkNames.filter((f) => f.endsWith('.mjs'));
-
-	if (files.length) {
-		await eslexer.init;
-
-		// Cleanup prerendered chunks.
-		// This has to happen AFTER the SSR build runs as a final step, because we need the code in order to generate the pages.
-		// These chunks should only contain prerendering logic, so they are safe to modify.
-		await Promise.all(
-			files.map(async (filename) => {
-				if (!prerenderedFiles.has(filename)) {
-					return;
-				}
-				const url = new URL(filename, out);
-				const text = await fs.promises.readFile(url, { encoding: 'utf8' });
-				const [, exports] = eslexer.parse(text);
-				// Replace exports (only prerendered pages) with a noop
-				let value = 'const noop = () => {};';
-				for (const e of exports) {
-					if (e.n === 'default') value += `\n export default noop;`;
-					else value += `\nexport const ${e.n} = noop;`;
+	await Promise.all(
+		internals.prerenderOnlyChunks.map(async (chunk) => {
+			const url = new URL(chunk.fileName, out);
+			try {
+				// Entry chunks may be referenced by non-deleted code, so we don't actually delete it
+				// but only empty its content. These chunks should never be executed in practice, but
+				// it should prevent broken import paths if adapters do a secondary bundle.
+				if (chunk.isEntry || chunk.isDynamicEntry) {
+					await fs.promises.writeFile(
+						url,
+						"// Contents removed by Astro as it's used for prerendering only",
+						'utf-8'
+					);
+				} else {
+					await fs.promises.unlink(url);
 				}
-				await fs.promises.writeFile(url, value, { encoding: 'utf8' });
-			})
-		);
-
-		removeEmptyDirs(out);
-	}
+			} catch {
+				// Best-effort only. Sometimes some chunks may be deleted by other plugins, like pure CSS chunks,
+				// so they may already not exist.
+			}
+		})
+	);
 }
 
 async function cleanServerOutput(
diff --git a/packages/astro/src/core/build/types.ts b/packages/astro/src/core/build/types.ts
index 53c6dcb93..b75b6415c 100644
--- a/packages/astro/src/core/build/types.ts
+++ b/packages/astro/src/core/build/types.ts
@@ -29,7 +29,6 @@ export interface PageBuildData {
 	moduleSpecifier: string;
 	hoistedScript: HoistedScriptAsset | undefined;
 	styles: Array<{ depth: number; order: number; sheet: StylesheetAsset }>;
-	hasSharedModules: boolean;
 }
 
 export type AllPagesData = Record<ComponentPath, PageBuildData>;
diff --git a/packages/astro/test/astro-assets-prefix.test.js b/packages/astro/test/astro-assets-prefix.test.js
index 08af026c1..4987c64e1 100644
--- a/packages/astro/test/astro-assets-prefix.test.js
+++ b/packages/astro/test/astro-assets-prefix.test.js
@@ -14,6 +14,11 @@ describe('Assets Prefix - Static', () => {
 	before(async () => {
 		fixture = await loadFixture({
 			root: './fixtures/astro-assets-prefix/',
+			outDir: './dist/static',
+			build: {
+				client: './dist/static/client',
+				server: './dist/static/server',
+			},
 		});
 		await fixture.build();
 	});
@@ -72,7 +77,10 @@ describe('Assets Prefix - with path prefix', () => {
 	before(async () => {
 		fixture = await loadFixture({
 			root: './fixtures/astro-assets-prefix/',
+			outDir: './dist/server',
 			build: {
+				client: './dist/server/client',
+				server: './dist/server/server',
 				assetsPrefix: '/starting-slash',
 			},
 		});
@@ -97,6 +105,11 @@ describe('Assets Prefix, server', () => {
 			root: './fixtures/astro-assets-prefix/',
 			output: 'server',
 			adapter: testAdapter(),
+			outDir: './dist/server',
+			build: {
+				client: './dist/server/client',
+				server: './dist/server/server',
+			},
 		});
 		await fixture.build();
 		app = await fixture.loadTestAdapterApp();
@@ -154,7 +167,10 @@ describe('Assets Prefix, with path prefix', () => {
 			root: './fixtures/astro-assets-prefix/',
 			output: 'server',
 			adapter: testAdapter(),
+			outDir: './dist/server-path-prefix',
 			build: {
+				client: './dist/server-path-prefix/client',
+				server: './dist/server-path-prefix/server',
 				assetsPrefix: '/starting-slash',
 			},
 		});
diff --git a/packages/astro/test/before-hydration.test.js b/packages/astro/test/before-hydration.test.js
index d14b347bf..75acafa00 100644
--- a/packages/astro/test/before-hydration.test.js
+++ b/packages/astro/test/before-hydration.test.js
@@ -14,6 +14,11 @@ describe('Astro Scripts before-hydration', () => {
 			before(async () => {
 				fixture = await loadFixture({
 					root: './fixtures/before-hydration/',
+					outDir: './dist/static-integration',
+					build: {
+						client: './dist/static-integration/client',
+						server: './dist/static-integration/server',
+					},
 					integrations: [
 						preact(),
 						{
@@ -68,6 +73,11 @@ describe('Astro Scripts before-hydration', () => {
 			before(async () => {
 				fixture = await loadFixture({
 					root: './fixtures/before-hydration/',
+					outDir: './dist/static-no-integration',
+					build: {
+						client: './dist/static-no-integration/client',
+						server: './dist/static-no-integration/server',
+					},
 				});
 			});
 
@@ -115,6 +125,11 @@ describe('Astro Scripts before-hydration', () => {
 					root: './fixtures/before-hydration/',
 					output: 'server',
 					adapter: testAdapter(),
+					outDir: './dist/server-integration',
+					build: {
+						client: './dist/server-integration/client',
+						server: './dist/server-integration/server',
+					},
 					integrations: [
 						preact(),
 						{
@@ -153,6 +168,11 @@ describe('Astro Scripts before-hydration', () => {
 				fixture = await loadFixture({
 					root: './fixtures/before-hydration/',
 					output: 'server',
+					outDir: './dist/static-no-integration',
+					build: {
+						client: './dist/static-no-integration/client',
+						server: './dist/static-no-integration/server',
+					},
 					adapter: testAdapter(),
 				});
 			});
diff --git a/packages/astro/test/core-image.test.js b/packages/astro/test/core-image.test.js
index a4fd13fcb..bb4ac3127 100644
--- a/packages/astro/test/core-image.test.js
+++ b/packages/astro/test/core-image.test.js
@@ -799,6 +799,11 @@ describe('astro:image', () => {
 			const fixtureWithBase = await loadFixture({
 				root: './fixtures/core-image-ssr/',
 				output: 'server',
+				outDir: './dist/server-base-path',
+				build: {
+					client: './dist/server-base-path/client',
+					server: './dist/server-base-path/server',
+				},
 				adapter: testAdapter(),
 				image: {
 					service: testImageService(),
@@ -1080,6 +1085,11 @@ describe('astro:image', () => {
 			fixture = await loadFixture({
 				root: './fixtures/core-image-ssr/',
 				output: 'server',
+				outDir: './dist/server-dev',
+				build: {
+					client: './dist/server-dev/client',
+					server: './dist/server-dev/server',
+				},
 				adapter: testAdapter(),
 				base: 'some-base',
 				image: {
@@ -1114,6 +1124,11 @@ describe('astro:image', () => {
 			fixture = await loadFixture({
 				root: './fixtures/core-image-ssr/',
 				output: 'server',
+				outDir: './dist/server-prod',
+				build: {
+					client: './dist/server-prod/client',
+					server: './dist/server-prod/server',
+				},
 				adapter: testAdapter(),
 				image: {
 					endpoint: 'astro/assets/endpoint/node',
@@ -1127,6 +1142,7 @@ describe('astro:image', () => {
 			const app = await fixture.loadTestAdapterApp();
 			let request = new Request('http://example.com/');
 			let response = await app.render(request);
+			console.log
 			assert.equal(response.status, 200);
 			const html = await response.text();
 			const $ = cheerio.load(html);
diff --git a/packages/astro/test/css-inline-stylesheets.test.js b/packages/astro/test/css-inline-stylesheets.test.js
index d066f530a..66a3da11e 100644
--- a/packages/astro/test/css-inline-stylesheets.test.js
+++ b/packages/astro/test/css-inline-stylesheets.test.js
@@ -15,7 +15,10 @@ describe('Setting inlineStylesheets to never in static output', () => {
 			site: 'https://test.dev/',
 			root: './fixtures/css-inline-stylesheets/',
 			output: 'static',
+			outDir: './dist/static-inline-stylesheets-never',
 			build: {
+				client: './dist/static-inline-stylesheets-never/client',
+				server: './dist/static-inline-stylesheets-never/server',
 				inlineStylesheets: 'never',
 			},
 		});
@@ -53,7 +56,10 @@ describe('Setting inlineStylesheets to never in server output', () => {
 			root: './fixtures/css-inline-stylesheets/',
 			output: 'server',
 			adapter: testAdapter(),
+			outDir: './dist/server-inline-stylesheets-never',
 			build: {
+				client: './dist/server-inline-stylesheets-never/client',
+				server: './dist/server-inline-stylesheets-never/server',
 				inlineStylesheets: 'never',
 			},
 		});
@@ -92,7 +98,10 @@ describe('Setting inlineStylesheets to auto in static output', () => {
 			site: 'https://test.info/',
 			root: './fixtures/css-inline-stylesheets/',
 			output: 'static',
+			outDir: './dist/static-inline-stylesheets-auto',
 			build: {
+				client: './dist/static-inline-stylesheets-auto/client',
+				server: './dist/static-inline-stylesheets-auto/server',
 				inlineStylesheets: 'auto',
 			},
 			vite: {
@@ -137,7 +146,10 @@ describe('Setting inlineStylesheets to auto in server output', () => {
 			root: './fixtures/css-inline-stylesheets/',
 			output: 'server',
 			adapter: testAdapter(),
+			outDir: './dist/server-inline-stylesheets-auto',
 			build: {
+				client: './dist/server-inline-stylesheets-auto/client',
+				server: './dist/server-inline-stylesheets-auto/server',
 				inlineStylesheets: 'auto',
 			},
 			vite: {
@@ -184,7 +196,10 @@ describe('Setting inlineStylesheets to always in static output', () => {
 			site: 'https://test.net/',
 			root: './fixtures/css-inline-stylesheets/',
 			output: 'static',
+			outDir: './dist/static-inline-stylesheets-always',
 			build: {
+				client: './dist/static-inline-stylesheets-always/client',
+				server: './dist/static-inline-stylesheets-always/server',
 				inlineStylesheets: 'always',
 			},
 		});
@@ -221,7 +236,10 @@ describe('Setting inlineStylesheets to always in server output', () => {
 			root: './fixtures/css-inline-stylesheets/',
 			output: 'server',
 			adapter: testAdapter(),
+			outDir: './dist/server-inline-stylesheets-always',
 			build: {
+				client: './dist/server-inline-stylesheets-always/client',
+				server: './dist/server-inline-stylesheets-always/server',
 				inlineStylesheets: 'always',
 			},
 		});
diff --git a/packages/astro/test/experimental-content-collections-css-inline-stylesheets.test.js b/packages/astro/test/experimental-content-collections-css-inline-stylesheets.test.js
index d6c509de5..5c02c66b5 100644
--- a/packages/astro/test/experimental-content-collections-css-inline-stylesheets.test.js
+++ b/packages/astro/test/experimental-content-collections-css-inline-stylesheets.test.js
@@ -59,7 +59,10 @@ describe('Experimental Content Collections cache - inlineStylesheets to never in
 			root: './fixtures/css-inline-stylesheets/',
 			output: 'server',
 			adapter: testAdapter(),
+			outDir: './dist/inline-stylesheets-never',
 			build: {
+				client: './dist/inline-stylesheets-never/client',
+				server: './dist/inline-stylesheets-never/server',
 				inlineStylesheets: 'never',
 			},
 			experimental: {
@@ -103,7 +106,10 @@ describe('Experimental Content Collections cache - inlineStylesheets to auto in
 			site: 'https://test.info/',
 			root: './fixtures/css-inline-stylesheets/',
 			output: 'static',
+			outDir: './dist/inline-stylesheets-auto',
 			build: {
+				client: './dist/inline-stylesheets-auto/client',
+				server: './dist/inline-stylesheets-auto/server',
 				inlineStylesheets: 'auto',
 			},
 			vite: {
@@ -202,7 +208,10 @@ describe('Setting inlineStylesheets to always in server output', () => {
 			root: './fixtures/css-inline-stylesheets/',
 			output: 'server',
 			adapter: testAdapter(),
+			outDir: './dist/inline-stylesheets-always',
 			build: {
+				client: './dist/inline-stylesheets-always/client',
+				server: './dist/inline-stylesheets-always/server',
 				inlineStylesheets: 'always',
 			},
 			experimental: {
diff --git a/packages/astro/test/fixtures/ssr-prerender-chunks/astro.config.mjs b/packages/astro/test/fixtures/ssr-prerender-chunks/astro.config.mjs
new file mode 100644
index 000000000..ad35a2317
--- /dev/null
+++ b/packages/astro/test/fixtures/ssr-prerender-chunks/astro.config.mjs
@@ -0,0 +1,10 @@
+import serverlessAdapter from '@test/ssr-prerender-chunks-test-adapter';
+ import { defineConfig } from 'astro/config';
+ import react from "@astrojs/react";
+
+ // https://astro.build/config
+ export default defineConfig({
+   adapter: serverlessAdapter(),
+   output: 'server',
+   integrations: [react()]
+ })
\ No newline at end of file
diff --git a/packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter/index.js b/packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter/index.js
new file mode 100644
index 000000000..82b7b64b1
--- /dev/null
+++ b/packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter/index.js
@@ -0,0 +1,85 @@
+/**
+  *
+  * @returns {import('../src/@types/astro').AstroIntegration}
+  */
+export default function () {
+  return {
+    name: '@test/ssr-prerender-chunks-test-adapter',
+    hooks: {
+      'astro:config:setup': ({ updateConfig, config }) => {
+        updateConfig({
+          build: {
+            client: config.outDir,
+            server: new URL('./_worker.js/', config.outDir),
+            serverEntry: 'index.js',
+            redirects: false,
+          }
+        });
+      },
+      'astro:config:done': ({ setAdapter }) => {
+        setAdapter({
+          name: '@test/ssr-prerender-chunks-test-adapter',
+          serverEntrypoint: '@test/ssr-prerender-chunks-test-adapter/server.js',
+          exports: ['default'],
+          supportedAstroFeatures: {
+            serverOutput: 'stable',
+          },
+        });
+      },
+      'astro:build:setup': ({ vite, target }) => {
+        if (target === 'server') {
+          vite.resolve ||= {};
+          vite.resolve.alias ||= {};
+
+          const aliases = [
+            {
+              find: 'react-dom/server',
+              replacement: 'react-dom/server.browser',
+            },
+          ];
+
+          if (Array.isArray(vite.resolve.alias)) {
+            vite.resolve.alias = [...vite.resolve.alias, ...aliases];
+          } else {
+            for (const alias of aliases) {
+              (vite.resolve.alias)[alias.find] = alias.replacement;
+            }
+          }
+
+          vite.resolve.conditions ||= [];
+          // We need those conditions, previous these conditions where applied at the esbuild step which we removed
+          // https://github.com/withastro/astro/pull/7092
+          vite.resolve.conditions.push('workerd', 'worker');
+
+          vite.ssr ||= {};
+          vite.ssr.target = 'webworker';
+          vite.ssr.noExternal = true;
+
+          vite.build ||= {};
+          vite.build.rollupOptions ||= {};
+          vite.build.rollupOptions.output ||= {};
+          vite.build.rollupOptions.output.banner ||=
+            'globalThis.process ??= {}; globalThis.process.env ??= {};';
+
+          // Cloudflare env is only available per request. This isn't feasible for code that access env vars
+          // in a global way, so we shim their access as `process.env.*`. This is not the recommended way for users to access environment variables. But we'll add this for compatibility for chosen variables. Mainly to support `@astrojs/db`
+          vite.define = {
+            'process.env': 'process.env',
+            ...vite.define,
+          };
+        }
+        // we thought that vite config inside `if (target === 'server')` would not apply for client
+        // but it seems like the same `vite` reference is used for both
+        // so we need to reset the previous conflicting setting
+        // in the future we should look into a more robust solution
+        if (target === 'client') {
+          vite.resolve ||= {};
+          vite.resolve.conditions ||= [];
+          vite.resolve.conditions = vite.resolve.conditions.filter(
+            (c) => c !== 'workerd' && c !== 'worker'
+          );
+        }
+      },
+    },
+  };
+}
\ No newline at end of file
diff --git a/packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter/package.json b/packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter/package.json
new file mode 100644
index 000000000..655ab8b54
--- /dev/null
+++ b/packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter/package.json
@@ -0,0 +1,10 @@
+{
+  "name": "@test/ssr-prerender-chunks-test-adapter",
+  "version": "0.0.0",
+  "private": true,
+  "type": "module",
+  "exports": {
+    ".": "./index.js",
+    "./server.js": "./server.js"
+  }
+}
diff --git a/packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter/server.js b/packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter/server.js
new file mode 100644
index 000000000..0921fe782
--- /dev/null
+++ b/packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter/server.js
@@ -0,0 +1,65 @@
+import { App } from 'astro/app';
+
+ export function createExports(manifest) {
+ 	const app = new App(manifest);
+
+ 	const fetch = async (
+ 		request,
+ 		env,
+ 		context
+ 	) => {
+ 		const { pathname } = new URL(request.url);
+
+ 		// static assets fallback, in case default _routes.json is not used
+ 		if (manifest.assets.has(pathname)) {
+ 			return env.ASSETS.fetch(request.url.replace(/\.html$/, ''));
+ 		}
+
+ 		const routeData = app.match(request);
+ 		if (!routeData) {
+ 			// https://developers.cloudflare.com/pages/functions/api-reference/#envassetsfetch
+ 			const asset = await env.ASSETS.fetch(
+ 				request.url.replace(/index.html$/, '').replace(/\.html$/, '')
+ 			);
+ 			if (asset.status !== 404) {
+ 				return asset;
+ 			}
+ 		}
+
+ 		Reflect.set(
+ 			request,
+ 			Symbol.for('astro.clientAddress'),
+ 			request.headers.get('cf-connecting-ip')
+ 		);
+
+ 		process.env.ASTRO_STUDIO_APP_TOKEN ??= (() => {
+ 			if (typeof env.ASTRO_STUDIO_APP_TOKEN === 'string') {
+ 				return env.ASTRO_STUDIO_APP_TOKEN;
+ 			}
+ 		})();
+
+ 		const locals = {
+ 			runtime: {
+ 				env: env,
+ 				cf: request.cf,
+ 				caches,
+ 				ctx: {
+ 					waitUntil: (promise) => context.waitUntil(promise),
+ 					passThroughOnException: () => context.passThroughOnException(),
+ 				},
+ 			},
+ 		};
+
+ 		const response = await app.render(request, { routeData, locals });
+
+ 		if (app.setCookieHeaders) {
+ 			for (const setCookieHeader of app.setCookieHeaders(response)) {
+ 				response.headers.append('Set-Cookie', setCookieHeader);
+ 			}
+ 		}
+
+ 		return response;
+ 	};
+
+ 	return { default: { fetch } };
+ }
\ No newline at end of file
diff --git a/packages/astro/test/fixtures/ssr-prerender-chunks/package.json b/packages/astro/test/fixtures/ssr-prerender-chunks/package.json
new file mode 100644
index 000000000..60896bdd6
--- /dev/null
+++ b/packages/astro/test/fixtures/ssr-prerender-chunks/package.json
@@ -0,0 +1,14 @@
+{
+  "name": "@test/ssr-prerender-chunks",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "@astrojs/react": "workspace:*",
+    "@test/ssr-prerender-chunks-test-adapter": "link:./deps/test-adapter",
+    "@types/react": "^18.2.75",
+    "@types/react-dom": "^18.2.24",
+    "astro": "workspace:*",
+    "react": "^18.2.0",
+    "react-dom": "^18.2.0"
+  }
+}
diff --git a/packages/astro/test/fixtures/ssr-prerender-chunks/src/components/Counter.tsx b/packages/astro/test/fixtures/ssr-prerender-chunks/src/components/Counter.tsx
new file mode 100644
index 000000000..c9fdcc2d9
--- /dev/null
+++ b/packages/astro/test/fixtures/ssr-prerender-chunks/src/components/Counter.tsx
@@ -0,0 +1,26 @@
+import React, { useState } from "react";
+
+ const Counter: React.FC = () => {
+     const [count, setCount] = useState<number>(0);
+
+     const increment = () => {
+         setCount((prevCount) => prevCount + 1);
+     };
+
+     const decrement = () => {
+         setCount((prevCount) => prevCount - 1);
+     };
+
+     return (
+         <div>
+             <h2>Counter</h2>
+             <div>
+                 <button onClick={decrement}>-</button>
+                 <span>{count}</span>
+                 <button onClick={increment}>+</button>
+             </div>
+         </div>
+     );
+ };
+
+ export default Counter;
\ No newline at end of file
diff --git a/packages/astro/test/fixtures/ssr-prerender-chunks/src/pages/index.astro b/packages/astro/test/fixtures/ssr-prerender-chunks/src/pages/index.astro
new file mode 100644
index 000000000..21a503211
--- /dev/null
+++ b/packages/astro/test/fixtures/ssr-prerender-chunks/src/pages/index.astro
@@ -0,0 +1,13 @@
+---
+ export const prerender = true;
+ import Counter from "../components/Counter";
+ ---
+
+ <html>
+ <head>
+ 	<title>Static Page</title>
+ </head>
+ 	<body>
+ 		<Counter client:load />
+ 	</body>
+ </html>
\ No newline at end of file
diff --git a/packages/astro/test/fixtures/ssr-prerender-chunks/tsconfig.json b/packages/astro/test/fixtures/ssr-prerender-chunks/tsconfig.json
new file mode 100644
index 000000000..7fb90fafc
--- /dev/null
+++ b/packages/astro/test/fixtures/ssr-prerender-chunks/tsconfig.json
@@ -0,0 +1,7 @@
+{
+  "extends": "astro/tsconfigs/base",
+  "compilerOptions": {
+    "jsx": "react-jsx",
+    "jsxImportSource": "react"
+  }
+}
\ No newline at end of file
diff --git a/packages/astro/test/i18n-routing.test.js b/packages/astro/test/i18n-routing.test.js
index 09581c899..df8083b81 100644
--- a/packages/astro/test/i18n-routing.test.js
+++ b/packages/astro/test/i18n-routing.test.js
@@ -1336,6 +1336,11 @@ describe('[SSR] i18n routing', () => {
 			fixture = await loadFixture({
 				root: './fixtures/i18n-routing-prefix-always/',
 				output: 'server',
+				outDir: './dist/pathname-prefix-always-no-redirect',
+				build: {
+					client: './dist/pathname-prefix-always-no-redirect/client',
+					server: './dist/pathname-prefix-always-no-redirect/server',
+				},
 				adapter: testAdapter(),
 				i18n: {
 					routing: {
@@ -1622,6 +1627,11 @@ describe('[SSR] i18n routing', () => {
 				fixture = await loadFixture({
 					root: './fixtures/i18n-routing/',
 					output: 'server',
+					outDir: './dist/locales-underscore',
+					build: {
+						client: './dist/locales-underscore/client',
+						server: './dist/locales-underscore/server',
+					},
 					adapter: testAdapter(),
 					i18n: {
 						defaultLocale: 'en',
@@ -1891,6 +1901,11 @@ describe('SSR fallback from missing locale index to default locale index', () =>
 		fixture = await loadFixture({
 			root: './fixtures/i18n-routing-prefix-other-locales/',
 			output: 'server',
+			outDir: './dist/missing-locale-to-default',
+			build: {
+				client: './dist/missing-locale-to-default/client',
+				server: './dist/missing-locale-to-default/server',
+			},
 			adapter: testAdapter(),
 			i18n: {
 				defaultLocale: 'en',
diff --git a/packages/astro/test/ssr-hoisted-script.test.js b/packages/astro/test/ssr-hoisted-script.test.js
index 41bae1ef5..70852f1db 100644
--- a/packages/astro/test/ssr-hoisted-script.test.js
+++ b/packages/astro/test/ssr-hoisted-script.test.js
@@ -25,7 +25,14 @@ describe('Hoisted inline scripts in SSR', () => {
 
 	describe('without base path', () => {
 		before(async () => {
-			fixture = await loadFixture(defaultFixtureOptions);
+			fixture = await loadFixture({
+				...defaultFixtureOptions,
+				outDir: './dist/inline-scripts-without-base-path',
+				build: {
+					client: './dist/inline-scripts-without-base-path/client',
+					server: './dist/inline-scripts-without-base-path/server',
+				},
+			});
 			await fixture.build();
 		});
 
@@ -42,6 +49,11 @@ describe('Hoisted inline scripts in SSR', () => {
 		before(async () => {
 			fixture = await loadFixture({
 				...defaultFixtureOptions,
+				outDir: './dist/inline-scripts-with-base-path',
+				build: {
+					client: './dist/inline-scripts-with-base-path/client',
+					server: './dist/inline-scripts-with-base-path/server',
+				},
 				base,
 			});
 			await fixture.build();
@@ -63,6 +75,11 @@ describe('Hoisted external scripts in SSR', () => {
 		before(async () => {
 			fixture = await loadFixture({
 				...defaultFixtureOptions,
+				outDir: './dist/external-scripts-without-base-path',
+				build: {
+					client: './dist/external-scripts-without-base-path/client',
+					server: './dist/external-scripts-without-base-path/server',
+				},
 				vite: {
 					build: {
 						assetsInlineLimit: 0,
@@ -83,6 +100,11 @@ describe('Hoisted external scripts in SSR', () => {
 		before(async () => {
 			fixture = await loadFixture({
 				...defaultFixtureOptions,
+				outDir: './dist/external-scripts-with-base-path',
+				build: {
+					client: './dist/external-scripts-with-base-path/client',
+					server: './dist/external-scripts-with-base-path/server',
+				},
 				vite: {
 					build: {
 						assetsInlineLimit: 0,
@@ -104,14 +126,17 @@ describe('Hoisted external scripts in SSR', () => {
 		before(async () => {
 			fixture = await loadFixture({
 				...defaultFixtureOptions,
+				outDir: './dist/with-assets-prefix',
+				build: {
+					client: './dist/with-assets-prefix/client',
+					server: './dist/with-assets-prefix/server',
+					assetsPrefix: 'https://cdn.example.com',
+				},
 				vite: {
 					build: {
 						assetsInlineLimit: 0,
 					},
 				},
-				build: {
-					assetsPrefix: 'https://cdn.example.com',
-				},
 			});
 			await fixture.build();
 		});
@@ -130,6 +155,11 @@ describe('Hoisted external scripts in SSR', () => {
 		before(async () => {
 			fixture = await loadFixture({
 				...defaultFixtureOptions,
+				outDir: './dist/with-rollup-output-file-names',
+				build: {
+					client: './dist/with-rollup-output-file-names/client',
+					server: './dist/with-rollup-output-file-names/server',
+				},
 				vite: {
 					build: {
 						assetsInlineLimit: 0,
@@ -157,6 +187,11 @@ describe('Hoisted external scripts in SSR', () => {
 		before(async () => {
 			fixture = await loadFixture({
 				...defaultFixtureOptions,
+				outDir: './dist/with-rollup-output-file-names-and-base',
+				build: {
+					client: './dist/with-rollup-output-file-names-and-base/client',
+					server: './dist/with-rollup-output-file-names-and-base/server',
+				},
 				vite: {
 					build: {
 						assetsInlineLimit: 0,
@@ -185,6 +220,12 @@ describe('Hoisted external scripts in SSR', () => {
 		before(async () => {
 			fixture = await loadFixture({
 				...defaultFixtureOptions,
+				outDir: './dist/with-rollup-output-file-names-and-assets-prefix',
+				build: {
+					client: './dist/with-rollup-output-file-names-and-assets-prefix/client',
+					server: './dist/with-rollup-output-file-names-and-assets-prefix/server',
+					assetsPrefix: 'https://cdn.example.com',
+				},
 				vite: {
 					build: {
 						assetsInlineLimit: 0,
@@ -197,9 +238,6 @@ describe('Hoisted external scripts in SSR', () => {
 						},
 					},
 				},
-				build: {
-					assetsPrefix: 'https://cdn.example.com',
-				},
 			});
 			await fixture.build();
 		});
diff --git a/packages/astro/test/ssr-prerender-chunks.test.js b/packages/astro/test/ssr-prerender-chunks.test.js
new file mode 100644
index 000000000..7bd916814
--- /dev/null
+++ b/packages/astro/test/ssr-prerender-chunks.test.js
@@ -0,0 +1,21 @@
+import assert from 'node:assert/strict';
+import { before, describe, it } from 'node:test';
+import { loadFixture } from './test-utils.js';
+
+describe('Chunks', () => {
+	/** @type {import('./test-utils').Fixture} */
+	let fixture;
+
+	before(async () => {
+		fixture = await loadFixture({
+			root: './fixtures/ssr-prerender-chunks/',
+		});
+		await fixture.build();
+	});
+
+	it('does not have wrong chunks', async () => {
+		const content = await fixture.readFile('_worker.js/renderers.mjs');
+		const hasImportFromPrerender = !content.includes(`React } from './chunks/prerender`);
+		assert.ok(hasImportFromPrerender);
+	});
+});
diff --git a/packages/astro/test/ssr-prerender.test.js b/packages/astro/test/ssr-prerender.test.js
index 2bf53cefa..a1620d752 100644
--- a/packages/astro/test/ssr-prerender.test.js
+++ b/packages/astro/test/ssr-prerender.test.js
@@ -12,6 +12,11 @@ describe('SSR: prerender', () => {
 		fixture = await loadFixture({
 			root: './fixtures/ssr-prerender/',
 			output: 'server',
+			outDir: './dist/normal',
+			build: {
+				client: './dist/normal/client',
+				server: './dist/normal/server',
+			},
 			adapter: testAdapter(),
 		});
 		await fixture.build();
@@ -61,7 +66,11 @@ describe('SSR: prerender', () => {
 	});
 });
 
-describe('Integrations can hook into the prerendering decision', () => {
+// NOTE: This test doesn't make sense as it relies on the fact that on the client build,
+// you can change the prerender state of pages from the SSR build, however, the client build
+// is not always guaranteed to run. If we want to support this feature, we may want to only allow
+// editing `route.prerender` on the `astro:build:done` hook.
+describe.skip('Integrations can hook into the prerendering decision', () => {
 	/** @type {import('./test-utils').Fixture} */
 	let fixture;
 
@@ -83,6 +92,11 @@ describe('Integrations can hook into the prerendering decision', () => {
 		fixture = await loadFixture({
 			root: './fixtures/ssr-prerender/',
 			output: 'server',
+			outDir: './dist/integration-prerender',
+			build: {
+				client: './dist/integration-prerender/client',
+				server: './dist/integration-prerender/server',
+			},
 			integrations: [testIntegration],
 			adapter: testAdapter(),
 		});
diff --git a/packages/astro/test/test-utils.js b/packages/astro/test/test-utils.js
index 65968a0bc..a4a4e22f8 100644
--- a/packages/astro/test/test-utils.js
+++ b/packages/astro/test/test-utils.js
@@ -216,6 +216,10 @@ export async function loadFixture(inlineConfig) {
 				});
 			}
 		},
+		loadAdapterEntryModule: async () => {
+			const url = new URL(`./server/entry.mjs?id=${fixtureId}`, config.outDir);
+			return await import(url);
+		},
 		loadNodeAdapterHandler: async () => {
 			const url = new URL(`./server/entry.mjs?id=${fixtureId}`, config.outDir);
 			const { handler } = await import(url);
diff --git a/packages/integrations/node/test/node-middleware.test.js b/packages/integrations/node/test/node-middleware.test.js
index fa496e871..d1b016a51 100644
--- a/packages/integrations/node/test/node-middleware.test.js
+++ b/packages/integrations/node/test/node-middleware.test.js
@@ -9,13 +9,6 @@ import { loadFixture, waitServerListen } from './test-utils.js';
  * @typedef {import('../../../astro/test/test-utils').Fixture} Fixture
  */
 
-async function load() {
-	const mod = await import(
-		`./fixtures/node-middleware/dist/server/entry.mjs?dropcache=${Date.now()}`
-	);
-	return mod;
-}
-
 describe('behavior from middleware, standalone', () => {
 	/** @type {import('./test-utils').Fixture} */
 	let fixture;
@@ -29,7 +22,7 @@ describe('behavior from middleware, standalone', () => {
 			adapter: nodejs({ mode: 'standalone' }),
 		});
 		await fixture.build();
-		const { startServer } = await load();
+		const { startServer } = await fixture.loadAdapterEntryModule();
 		let res = startServer();
 		server = res.server;
 		await waitServerListen(server.server);
@@ -69,7 +62,7 @@ describe('behavior from middleware, middleware', () => {
 			adapter: nodejs({ mode: 'middleware' }),
 		});
 		await fixture.build();
-		const { handler } = await load();
+		const { handler } = await fixture.loadAdapterEntryModule();
 		const app = express();
 		app.use(handler);
 		server = app.listen(8888);
diff --git a/packages/integrations/node/test/prerender-404-500.test.js b/packages/integrations/node/test/prerender-404-500.test.js
index afa23a151..2535fcb35 100644
--- a/packages/integrations/node/test/prerender-404-500.test.js
+++ b/packages/integrations/node/test/prerender-404-500.test.js
@@ -8,13 +8,6 @@ import { loadFixture, waitServerListen } from './test-utils.js';
  * @typedef {import('../../../astro/test/test-utils').Fixture} Fixture
  */
 
-async function load() {
-	const mod = await import(
-		`./fixtures/prerender-404-500/dist/server/entry.mjs?dropcache=${Date.now()}`
-	);
-	return mod;
-}
-
 describe('Prerender 404', () => {
 	/** @type {import('./test-utils').Fixture} */
 	let fixture;
@@ -32,10 +25,15 @@ describe('Prerender 404', () => {
 				base: '/some-base',
 				root: './fixtures/prerender-404-500/',
 				output: 'server',
+				outDir: './dist/server-with-base',
+				build: {
+					client: './dist/server-with-base/client',
+					server: './dist/server-with-base/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			await fixture.build();
-			const { startServer } = await load();
+			const { startServer } = await fixture.loadAdapterEntryModule();
 			let res = startServer();
 			server = res.server;
 			await waitServerListen(server.server);
@@ -117,10 +115,15 @@ describe('Prerender 404', () => {
 				site: 'https://test.info/',
 				root: './fixtures/prerender-404-500/',
 				output: 'server',
+				outDir: './dist/server-without-base',
+				build: {
+					client: './dist/server-without-base/client',
+					server: './dist/server-without-base/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			await fixture.build();
-			const { startServer } = await load();
+			const { startServer } = await fixture.loadAdapterEntryModule();
 			let res = startServer();
 			server = res.server;
 			await waitServerListen(server.server);
@@ -181,10 +184,15 @@ describe('Hybrid 404', () => {
 				base: '/some-base',
 				root: './fixtures/prerender-404-500/',
 				output: 'hybrid',
+				outDir: './dist/hybrid-with-base',
+				build: {
+					client: './dist/hybrid-with-base/client',
+					server: './dist/hybrid-with-base/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			await fixture.build();
-			const { startServer } = await load();
+			const { startServer } = await fixture.loadAdapterEntryModule();
 			let res = startServer();
 			server = res.server;
 			await waitServerListen(server.server);
@@ -238,10 +246,15 @@ describe('Hybrid 404', () => {
 				site: 'https://test.net/',
 				root: './fixtures/prerender-404-500/',
 				output: 'hybrid',
+				outDir: './dist/hybrid-without-base',
+				build: {
+					client: './dist/hybrid-without-base/client',
+					server: './dist/hybrid-without-base/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			await fixture.build();
-			const { startServer } = await load();
+			const { startServer } = await fixture.loadAdapterEntryModule();
 			let res = startServer();
 			server = res.server;
 			await waitServerListen(server.server);
diff --git a/packages/integrations/node/test/prerender.test.js b/packages/integrations/node/test/prerender.test.js
index 29080981a..d856d9d3e 100644
--- a/packages/integrations/node/test/prerender.test.js
+++ b/packages/integrations/node/test/prerender.test.js
@@ -8,10 +8,6 @@ import { loadFixture, waitServerListen } from './test-utils.js';
  * @typedef {import('../../../astro/test/test-utils').Fixture} Fixture
  */
 
-async function load() {
-	const mod = await import(`./fixtures/prerender/dist/server/entry.mjs?dropcache=${Date.now()}`);
-	return mod;
-}
 describe('Prerendering', () => {
 	/** @type {import('./test-utils').Fixture} */
 	let fixture;
@@ -25,10 +21,15 @@ describe('Prerendering', () => {
 				base: '/some-base',
 				root: './fixtures/prerender/',
 				output: 'server',
+				outDir: './dist/with-base',
+				build: {
+					client: './dist/with-base/client',
+					server: './dist/with-base/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			await fixture.build();
-			const { startServer } = await load();
+			const { startServer } = await fixture.loadAdapterEntryModule();
 			let res = startServer();
 			server = res.server;
 			await waitServerListen(server.server);
@@ -94,10 +95,15 @@ describe('Prerendering', () => {
 			fixture = await loadFixture({
 				root: './fixtures/prerender/',
 				output: 'server',
+				outDir: './dist/without-base',
+				build: {
+					client: './dist/without-base/client',
+					server: './dist/without-base/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			await fixture.build();
-			const { startServer } = await await load();
+			const { startServer } = await fixture.loadAdapterEntryModule();
 			let res = startServer();
 			server = res.server;
 			await waitServerListen(server.server);
@@ -155,6 +161,11 @@ describe('Prerendering', () => {
 			fixture = await loadFixture({
 				root: './fixtures/prerender/',
 				output: 'server',
+				outDir: './dist/dev',
+				build: {
+					client: './dist/dev/client',
+					server: './dist/dev/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			devServer = await fixture.startDevServer();
@@ -197,10 +208,15 @@ describe('Hybrid rendering', () => {
 				base: '/some-base',
 				root: './fixtures/prerender/',
 				output: 'hybrid',
+				outDir: './dist/hybrid-with-base',
+				build: {
+					client: './dist/hybrid-with-base/client',
+					server: './dist/hybrid-with-base/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			await fixture.build();
-			const { startServer } = await load();
+			const { startServer } = await fixture.loadAdapterEntryModule();
 			let res = startServer();
 			server = res.server;
 			await waitServerListen(server.server);
@@ -264,10 +280,15 @@ describe('Hybrid rendering', () => {
 			fixture = await loadFixture({
 				root: './fixtures/prerender/',
 				output: 'hybrid',
+				outDir: './dist/hybrid-without-base',
+				build: {
+					client: './dist/hybrid-without-base/client',
+					server: './dist/hybrid-without-base/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			await fixture.build();
-			const { startServer } = await load();
+			const { startServer } = await fixture.loadAdapterEntryModule();
 			let res = startServer();
 			server = res.server;
 			await waitServerListen(server.server);
@@ -323,10 +344,15 @@ describe('Hybrid rendering', () => {
 			fixture = await loadFixture({
 				root: './fixtures/prerender/',
 				output: 'hybrid',
+				outDir: './dist/hybrid-shared-modules',
+				build: {
+					client: './dist/hybrid-shared-modules/client',
+					server: './dist/hybrid-shared-modules/server',
+				},
 				adapter: nodejs({ mode: 'standalone' }),
 			});
 			await fixture.build();
-			const { startServer } = await load();
+			const { startServer } = await fixture.loadAdapterEntryModule();
 			let res = startServer();
 			server = res.server;
 			await waitServerListen(server.server);
diff --git a/packages/integrations/node/test/trailing-slash.test.js b/packages/integrations/node/test/trailing-slash.test.js
index ad91a2759..9ea8fcddd 100644
--- a/packages/integrations/node/test/trailing-slash.test.js
+++ b/packages/integrations/node/test/trailing-slash.test.js
@@ -8,13 +8,6 @@ import { loadFixture, waitServerListen } from './test-utils.js';
  * @typedef {import('../../../astro/test/test-utils').Fixture} Fixture
  */
 
-async function load() {
-	const mod = await import(
-		`./fixtures/trailing-slash/dist/server/entry.mjs?dropcache=${Date.now()}`
-	);
-	return mod;
-}
-
 describe('Trailing slash', () => {
 	/** @type {import('./test-utils').Fixture} */
 	let fixture;
@@ -30,10 +23,15 @@ describe('Trailing slash', () => {
 					base: '/some-base',
 					output: 'hybrid',
 					trailingSlash: 'always',
+					outDir: './dist/always-with-base',
+					build: {
+						client: './dist/always-with-base/client',
+						server: './dist/always-with-base/server',
+					},
 					adapter: nodejs({ mode: 'standalone' }),
 				});
 				await fixture.build();
-				const { startServer } = await load();
+				const { startServer } = await fixture.loadAdapterEntryModule();
 				let res = startServer();
 				server = res.server;
 				await waitServerListen(server.server);
@@ -96,10 +94,15 @@ describe('Trailing slash', () => {
 					root: './fixtures/trailing-slash/',
 					output: 'hybrid',
 					trailingSlash: 'always',
+					outDir: './dist/always-without-base',
+					build: {
+						client: './dist/always-without-base/client',
+						server: './dist/always-without-base/server',
+					},
 					adapter: nodejs({ mode: 'standalone' }),
 				});
 				await fixture.build();
-				const { startServer } = await load();
+				const { startServer } = await fixture.loadAdapterEntryModule();
 				let res = startServer();
 				server = res.server;
 				await waitServerListen(server.server);
@@ -165,10 +168,15 @@ describe('Trailing slash', () => {
 					base: '/some-base',
 					output: 'hybrid',
 					trailingSlash: 'never',
+					outDir: './dist/never-with-base',
+					build: {
+						client: './dist/never-with-base/client',
+						server: './dist/never-with-base/server',
+					},
 					adapter: nodejs({ mode: 'standalone' }),
 				});
 				await fixture.build();
-				const { startServer } = await load();
+				const { startServer } = await fixture.loadAdapterEntryModule();
 				let res = startServer();
 				server = res.server;
 				await waitServerListen(server.server);
@@ -224,10 +232,15 @@ describe('Trailing slash', () => {
 					root: './fixtures/trailing-slash/',
 					output: 'hybrid',
 					trailingSlash: 'never',
+					outDir: './dist/never-without-base',
+					build: {
+						client: './dist/never-without-base/client',
+						server: './dist/never-without-base/server',
+					},
 					adapter: nodejs({ mode: 'standalone' }),
 				});
 				await fixture.build();
-				const { startServer } = await load();
+				const { startServer } = await fixture.loadAdapterEntryModule();
 				let res = startServer();
 				server = res.server;
 				await waitServerListen(server.server);
@@ -286,10 +299,15 @@ describe('Trailing slash', () => {
 					base: '/some-base',
 					output: 'hybrid',
 					trailingSlash: 'ignore',
+					outDir: './dist/ignore-with-base',
+					build: {
+						client: './dist/ignore-with-base/client',
+						server: './dist/ignore-with-base/server',
+					},
 					adapter: nodejs({ mode: 'standalone' }),
 				});
 				await fixture.build();
-				const { startServer } = await load();
+				const { startServer } = await fixture.loadAdapterEntryModule();
 				let res = startServer();
 				server = res.server;
 				await waitServerListen(server.server);
@@ -363,10 +381,15 @@ describe('Trailing slash', () => {
 					root: './fixtures/trailing-slash/',
 					output: 'hybrid',
 					trailingSlash: 'ignore',
+					outDir: './dist/ignore-without-base',
+					build: {
+						client: './dist/ignore-without-base/client',
+						server: './dist/ignore-without-base/server',
+					},
 					adapter: nodejs({ mode: 'standalone' }),
 				});
 				await fixture.build();
-				const { startServer } = await load();
+				const { startServer } = await fixture.loadAdapterEntryModule();
 				let res = startServer();
 				server = res.server;
 				await waitServerListen(server.server);
diff --git a/packages/integrations/vercel/test/serverless-prerender.test.js b/packages/integrations/vercel/test/serverless-prerender.test.js
index 537eef77c..5b75418c9 100644
--- a/packages/integrations/vercel/test/serverless-prerender.test.js
+++ b/packages/integrations/vercel/test/serverless-prerender.test.js
@@ -20,7 +20,7 @@ describe('Serverless prerender', () => {
 
 	it('outDir is tree-shaken if not needed', async () => {
 		const [file] = await fixture.glob(
-			'../.vercel/output/functions/_render.func/packages/integrations/vercel/test/fixtures/serverless-prerender/.vercel/output/_functions/chunks/pages/generic_*.mjs'
+			'../.vercel/output/functions/_render.func/packages/integrations/vercel/test/fixtures/serverless-prerender/.vercel/output/_functions/pages/_image.astro.mjs'
 		);
 		const contents = await fixture.readFile(file);
 		assert.ok(!contents.includes('const outDir ='), "outDir is tree-shaken if it's not imported");
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 1194721fb..b5aadde6d 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -3781,6 +3781,32 @@ importers:
         specifier: workspace:*
         version: link:../../..
 
+  packages/astro/test/fixtures/ssr-prerender-chunks:
+    dependencies:
+      '@astrojs/react':
+        specifier: workspace:*
+        version: link:../../../../integrations/react
+      '@test/ssr-prerender-chunks-test-adapter':
+        specifier: link:./deps/test-adapter
+        version: link:deps/test-adapter
+      '@types/react':
+        specifier: ^18.2.75
+        version: 18.3.3
+      '@types/react-dom':
+        specifier: ^18.2.24
+        version: 18.3.0
+      astro:
+        specifier: workspace:*
+        version: link:../../..
+      react:
+        specifier: ^18.2.0
+        version: 18.3.1
+      react-dom:
+        specifier: ^18.2.0
+        version: 18.3.1(react@18.3.1)
+
+  packages/astro/test/fixtures/ssr-prerender-chunks/deps/test-adapter: {}
+
   packages/astro/test/fixtures/ssr-prerender-get-static-paths:
     dependencies:
       astro: