diff --git a/utils/docs-api.test.ts b/utils/docs-api.test.ts
index 283ae4c..d1b278c 100644
--- a/utils/docs-api.test.ts
+++ b/utils/docs-api.test.ts
@@ -32,4 +32,17 @@ describe('docs api', () => {
       expect(item).toEqual({ path: item.path, type: 'blob', sha: blobSha(raw) })
     }
   })
+
+  it('bundles every source with the sha git would give it', async () => {
+    const outDir = await mkdtemp(path.join(tmpdir(), 'docs-api-'))
+    outDirs.push(outDir)
+    await publishSources('.', outDir, ['index.md', 'about/index.md'])
+
+    const bundle = JSON.parse(await readFile(path.join(outDir, 'docs-api/bundle.json'), 'utf8'))
+    expect(bundle.files.map((file: { path: string }) => file.path)).toEqual(['about/index.md', 'index.md'])
+    for (const file of bundle.files) {
+      const expected = execFileSync('git', ['hash-object', file.path], { encoding: 'utf8' }).trim()
+      expect(file).toEqual({ path: file.path, sha: expected, content: await readFile(file.path, 'utf8') })
+    }
+  })
 })
diff --git a/utils/docs-api.ts b/utils/docs-api.ts
index cff4e08..319cfe5 100644
--- a/utils/docs-api.ts
+++ b/utils/docs-api.ts
@@ -9,12 +9,14 @@ export function blobSha(bytes: Uint8Array): string {
 // Same shape as GitHub's recursive tree response, so @nbtca/docs reads both with one parser.
 export async function publishSources(srcDir: string, outDir: string, pages: string[]): Promise<void> {
   const root = path.join(outDir, 'docs-api')
-  const tree = await Promise.all([...pages].sort().map(async (page) => {
+  const files = await Promise.all([...pages].sort().map(async (page) => {
     const bytes = await readFile(path.join(srcDir, page))
     const target = path.join(root, 'raw', page)
     await mkdir(path.dirname(target), { recursive: true })
     await writeFile(target, bytes)
-    return { path: page, type: 'blob', sha: blobSha(bytes) }
+    return { path: page, sha: blobSha(bytes), content: bytes.toString('utf8') }
   }))
+  const tree = files.map(file => ({ path: file.path, type: 'blob', sha: file.sha }))
   await writeFile(path.join(root, 'index.json'), JSON.stringify({ tree, truncated: false }))
+  await writeFile(path.join(root, 'bundle.json'), JSON.stringify({ files }))
 }