diff --git a/src/bundler.ts b/src/bundler.ts
index 4c096bcc..1dada348 100644
--- a/src/bundler.ts
+++ b/src/bundler.ts
@@ -7,6 +7,7 @@ import { v4 as uuidv4 } from 'uuid'
 import { DenoBridge, LifecycleHook } from './bridge.js'
 import type { Bundle } from './bundle.js'
 import type { Declaration } from './declaration.js'
+import { EdgeFunction } from './edge_function.js'
 import { FeatureFlags, getFlags } from './feature_flags.js'
 import { findFunctions } from './finder.js'
 import { bundle as bundleESZIP } from './formats/eszip.js'
@@ -24,7 +25,56 @@ interface BundleOptions {
   onBeforeDownload?: LifecycleHook
 }
 
-// eslint-disable-next-line max-statements
+interface BundleFormatOptions {
+  buildID: string
+  debug?: boolean
+  deno: DenoBridge
+  distDirectory: string
+  functions: EdgeFunction[]
+  featureFlags: Record<string, string>
+  importMap: ImportMap
+  basePath: string
+}
+
+const createBundleOps = ({
+  basePath,
+  buildID,
+  debug,
+  deno,
+  distDirectory,
+  functions,
+  importMap,
+  featureFlags,
+}: BundleFormatOptions) => {
+  const bundleOps = []
+
+  if (featureFlags.edge_functions_produce_eszip) {
+    bundleOps.push(
+      bundleESZIP({
+        basePath,
+        buildID,
+        debug,
+        deno,
+        distDirectory,
+        functions,
+      }),
+    )
+  } else {
+    bundleOps.push(
+      bundleJS({
+        buildID,
+        debug,
+        deno,
+        distDirectory,
+        functions,
+        importMap,
+      }),
+    )
+  }
+
+  return bundleOps
+}
+
 const bundle = async (
   sourceDirectories: string[],
   distDirectory: string,
@@ -57,31 +107,17 @@ const bundle = async (
   // if any.
   const importMap = new ImportMap(importMaps)
   const functions = await findFunctions(sourceDirectories)
-  const bundleOps = []
 
-  if (featureFlags.edge_functions_produce_eszip) {
-    bundleOps.push(
-      bundleESZIP({
-        basePath,
-        buildID,
-        debug,
-        deno,
-        distDirectory,
-        functions,
-      }),
-    )
-  } else {
-    bundleOps.push(
-      bundleJS({
-        buildID,
-        debug,
-        deno,
-        distDirectory,
-        functions,
-        importMap,
-      }),
-    )
-  }
+  const bundleOps = createBundleOps({
+    basePath,
+    buildID,
+    debug,
+    deno,
+    distDirectory,
+    functions,
+    importMap,
+    featureFlags,
+  })
 
   const bundles = await Promise.all(bundleOps)
 
@@ -90,7 +126,7 @@ const bundle = async (
   // rename the bundles to their permanent names.
   await createFinalBundles(bundles, distDirectory, buildID)
 
-  await writeManifest({
+  const manifest = await writeManifest({
     bundles,
     declarations,
     distDirectory,
@@ -101,7 +137,7 @@ const bundle = async (
     await importMap.writeToFile(distImportMapPath)
   }
 
-  return { functions }
+  return { functions, manifest }
 }
 
 const createFinalBundles = async (bundles: Bundle[], distDirectory: string, buildID: string) => {
diff --git a/src/manifest.ts b/src/manifest.ts
index bd3213b1..20fbb69f 100644
--- a/src/manifest.ts
+++ b/src/manifest.ts
@@ -75,11 +75,13 @@ interface WriteManifestOptions {
   functions: EdgeFunction[]
 }
 
-const writeManifest = ({ bundles, declarations = [], distDirectory, functions }: WriteManifestOptions) => {
+const writeManifest = async ({ bundles, declarations = [], distDirectory, functions }: WriteManifestOptions) => {
   const manifest = generateManifest({ bundles, declarations, functions })
   const manifestPath = join(distDirectory, 'manifest.json')
 
-  return fs.writeFile(manifestPath, JSON.stringify(manifest))
+  await fs.writeFile(manifestPath, JSON.stringify(manifest))
+
+  return manifest
 }
 
 export { generateManifest, Manifest, writeManifest }
diff --git a/test/bundler.ts b/test/bundler.ts
index 9445ce9e..7f6750ef 100644
--- a/test/bundler.ts
+++ b/test/bundler.ts
@@ -34,6 +34,7 @@ test('Produces a JavaScript bundle and a manifest file', async (t) => {
   t.is(bundles.length, 1)
   t.is(bundles[0].format, 'js')
   t.true(generatedFiles.includes(bundles[0].asset))
+  t.deepEqual(result.manifest, manifest)
 
   await fs.rmdir(tmpDir.path, { recursive: true })
 })