diff --git a/extensions/res/download.ts b/extensions/res/download.ts
index 2bb59e5..6087960 100644
--- a/extensions/res/download.ts
+++ b/extensions/res/download.ts
@@ -9,21 +9,31 @@ export type DownloadOptions =
     headers: Record<string, unknown>
   }>
 
+type Callback = (err?: unknown) => void
+
 export const download = <
   Req extends Request = Request,
   Res extends DummyResponse = DummyResponse,
 >(req: Req, res: Res) =>
 async (
   path: string,
-  filename?: string,
-  options: DownloadOptions = {},
+  filename?: string | Callback,
+  options?: DownloadOptions | Callback,
+  cb?: Callback,
 ): Promise<Res> => {
-  const name: string | null = filename as string
-  let opts: DownloadOptions = options
-
+  let name: string | null = filename as string
+  let done = cb
+  let opts: DownloadOptions = (options || null) as DownloadOptions
+  if (typeof filename === 'function') {
+    done = filename
+    name = null
+  } else if (typeof options === 'function') {
+    done = options
+  }
+  opts = opts || {}
   // set Content-Disposition when file is sent
   const headers: Record<string, string> = {
-    'Content-Disposition': contentDisposition(name || path),
+    'Content-Disposition': contentDisposition(basename(name || path)),
   }
 
   // merge user-provided headers
@@ -34,13 +44,16 @@ async (
       }
     }
   }
-
   // merge user-provided options
   opts = { ...opts, headers }
 
   // send file
 
-  return await sendFile<Req, Res>(req, res)(path, opts)
+  return await sendFile<Req, Res>(req, res)(
+    path,
+    opts,
+    done || (() => undefined),
+  )
 }
 
 export const attachment =
diff --git a/extensions/res/send/sendFile.ts b/extensions/res/send/sendFile.ts
index 3f3bbfe..e6c20fa 100644
--- a/extensions/res/send/sendFile.ts
+++ b/extensions/res/send/sendFile.ts
@@ -26,15 +26,17 @@ export const sendFile = <
   Req extends Request = Request,
   Res extends DummyResponse = DummyResponse,
 >(req: Req, res: Res) =>
-async (path: string, { signal, ...opts }: SendFileOptions = {}) => {
+async (
+  path: string,
+  { signal, ...opts }: SendFileOptions = {},
+  cb?: (err?: unknown) => void,
+) => {
   const { root, headers = {}, encoding = 'utf-8', ...options } = opts
-
   if (!_path.isAbsolute(path) && !root) {
     throw new TypeError('path must be absolute')
   }
 
   const filePath = root ? _path.join(root, path) : path
-
   const stats = await Deno.stat(filePath)
 
   headers['Content-Encoding'] = encoding
@@ -48,7 +50,6 @@ async (path: string, { signal, ...opts }: SendFileOptions = {}) => {
 
   headers['Content-Security-Policy'] = 'default-src \'none\''
   headers['X-Content-Type-Options'] = 'nosniff'
-
   let status = 200
 
   if (req.headers.get('range')) {
@@ -74,8 +75,13 @@ async (path: string, { signal, ...opts }: SendFileOptions = {}) => {
 
   res._init.status = status
 
-  const file = await Deno.readFile(path, { signal })
-
+  let file
+  try {
+    file = await Deno.readFile(filePath, { signal })
+  } catch (error) {
+    cb!(error)
+    file = null
+  }
   await send(req, res)(file)
 
   return res
diff --git a/router.ts b/router.ts
index 23f40cb..814cc40 100644
--- a/router.ts
+++ b/router.ts
@@ -228,6 +228,17 @@ export class Router<
 
     return this
   }
+
+  all(...args: UseMethodParams): this {
+    const handlers = args.slice(1).flat()
+    pushMiddleware(this.middleware)({
+      path: args[0] as Handler,
+      handler: handlers[0] as Handler,
+      handlers: handlers.slice(1) as Handler[],
+      type: 'route',
+    })
+    return this
+  }
   /**
    * Return the app's absolute pathname
    * based on the parent(s) that have
diff --git a/tests/core/app.test.ts b/tests/core/app.test.ts
index 4137fd6..a75ec93 100644
--- a/tests/core/app.test.ts
+++ b/tests/core/app.test.ts
@@ -134,19 +134,16 @@ describe('Testing App routing', () => {
     )
     ;(await makeFetch(app.handler)('/abcdef')).expect(404)
   })
-  // it('"*" should catch all undefined routes', async () => {
-  //   const app = new App()
-
-  //   const server = app.handler
-
-  //   app
-  //     .get('/route', (_req, res) => void res.send('A different route'))
-  //     .all('*', (_req, res) => void res.send('Hello world'))
-
-  //   await makeFetch(server)('/route').expect(200, 'A different route')
-
-  //   await makeFetch(server)('/test').expect(200, 'Hello world')
-  // })
+  it('"*" should catch all undefined routes', async () => {
+    const app = new App()
+    app.get(
+      '/route',
+      async (_req, res) => void await res.send('A different route'),
+    )
+    app.all('*', async (_req, res) => void await res.send('Hello world'))
+    ;(await makeFetch(app.handler)('/route')).expect('A different route')
+    ;(await makeFetch(app.handler)('/test')).expect('Hello world')
+  })
   it('should throw 404 on no routes', async () => {
     const app = new App()
     const fetch = makeFetch(app.handler)
@@ -371,166 +368,132 @@ describe('HTTP methods', () => {
     const res = await fetch('/', { method: 'PATCH' })
     res.expect('PATCH')
   })
-  // it('app.head handles head request', async () => {
-  //   const app = new App()
-
-  //   app.head('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'HEAD' }).expect(200, '')
-  // })
-  // it('app.delete handles delete request', async () => {
-  //   const app = new App()
-
-  //   app.delete('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'DELETE' }).expect(200, 'DELETE')
-  // })
-  // it('app.checkout handles checkout request', async () => {
-  //   const app = new App()
-
-  //   app.checkout('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'CHECKOUT' }).expect(200, 'CHECKOUT')
-  // })
-  // it('app.copy handles copy request', async () => {
-  //   const app = new App()
-
-  //   app.copy('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'COPY' }).expect(200, 'COPY')
-  // })
-  // it('app.lock handles lock request', async () => {
-  //   const app = new App()
-
-  //   app.lock('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'LOCK' }).expect(200, 'LOCK')
-  // })
-  // it('app.merge handles merge request', async () => {
-  //   const app = new App()
-
-  //   app.merge('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'MERGE' }).expect(200, 'MERGE')
-  // })
-  // it('app.mkactivity handles mkactivity request', async () => {
-  //   const app = new App()
-
-  //   app.mkactivity('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'MKACTIVITY' }).expect(200, 'MKACTIVITY')
-  // })
-  // it('app.mkcol handles mkcol request', async () => {
-  //   const app = new App()
-
-  //   app.mkcol('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'MKCOL' }).expect(200, 'MKCOL')
-  // })
-  // it('app.move handles move request', async () => {
-  //   const app = new App()
-
-  //   app.move('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'MOVE' }).expect(200, 'MOVE')
-  // })
-  // it('app.search handles search request', async () => {
-  //   const app = new App()
-
-  //   app.search('/', (req, res) => void res.end(req.method))
-
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
-
-  //   await fetch('/', { method: 'SEARCH' }).expect(200, 'SEARCH')
-  // })
-  // it('app.notify handles notify request', async () => {
-  //   const app = new App()
+  it('app.head handles head request', async () => {
+    const app = new App()
 
-  //   app.notify('/', (req, res) => void res.end(req.method))
+    app.head('/', (req, res) => void res.end(req.method))
 
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
+    const fetch = makeFetch(app.handler)
 
-  //   await fetch('/', { method: 'NOTIFY' }).expect(200, 'NOTIFY')
-  // })
-  // it('app.purge handles purge request', async () => {
-  //   const app = new App()
+    const res = await fetch('/', { method: 'HEAD' })
+    res.expect('HEAD', null)
+  })
+  it('app.delete handles delete request', async () => {
+    const app = new App()
 
-  //   app.purge('/', (req, res) => void res.end(req.method))
+    app.delete('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'DELETE' })).expect(
+      'DELETE',
+    )
+  })
+  it('app.checkout handles checkout request', async () => {
+    const app = new App()
 
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
+    app.checkout('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'CHECKOUT' })).expect(
+      'CHECKOUT',
+    )
+  })
+  it('app.copy handles copy request', async () => {
+    const app = new App()
 
-  //   await fetch('/', { method: 'PURGE' }).expect(200, 'PURGE')
-  // })
-  // it('app.report handles report request', async () => {
-  //   const app = new App()
+    app.copy('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'COPY' })).expect('COPY')
+  })
+  it('app.lock handles lock request', async () => {
+    const app = new App()
 
-  //   app.report('/', (req, res) => void res.end(req.method))
+    app.lock('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'LOCK' })).expect('LOCK')
+  })
+  it('app.merge handles merge request', async () => {
+    const app = new App()
 
-  //   const fetch = makeFetch(app.handler)
+    app.merge('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'MERGE' })).expect(
+      'MERGE',
+    )
+  })
+  it('app.mkactivity handles mkactivity request', async () => {
+    const app = new App()
 
-  //   await fetch('/', { method: 'REPORT' }).expect(200, 'REPORT')
-  // })
-  // it('app.subscribe handles subscribe request', async () => {
-  //   const app = new App()
+    app.mkactivity('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'MKACTIVITY' })).expect(
+      'MKACTIVITY',
+    )
+  })
+  it('app.mkcol handles mkcol request', async () => {
+    const app = new App()
 
-  //   app.subscribe('/', (req, res) => void res.end(req.method))
+    app.mkcol('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'MKCOL' })).expect(
+      'MKCOL',
+    )
+  })
+  it('app.move handles move request', async () => {
+    const app = new App()
 
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
+    app.move('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'MOVE' })).expect('MOVE')
+  })
+  it('app.search handles search request', async () => {
+    const app = new App()
 
-  //   await fetch('/', { method: 'SUBSCRIBE' }).expect(200, 'SUBSCRIBE')
-  // })
-  // it('app.unsubscribe handles unsubscribe request', async () => {
-  //   const app = new App()
+    app.search('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'SEARCH' })).expect(
+      'SEARCH',
+    )
+  })
+  it('app.notify handles notify request', async () => {
+    const app = new App()
 
-  //   app.unsubscribe('/', (req, res) => void res.end(req.method))
+    app.notify('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'NOTIFY' })).expect(
+      'NOTIFY',
+    )
+  })
+  it('app.purge handles purge request', async () => {
+    const app = new App()
 
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
+    app.purge('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'PURGE' })).expect(
+      'PURGE',
+    )
+  })
+  it('app.report handles report request', async () => {
+    const app = new App()
 
-  //   await fetch('/', { method: 'UNSUBSCRIBE' }).expect(200, 'UNSUBSCRIBE')
-  // })
-  // it('app.trace handles trace request', async () => {
-  //   const app = new App()
+    app.report('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'REPORT' })).expect(
+      'REPORT',
+    )
+  })
+  it('app.subscribe handles subscribe request', async () => {
+    const app = new App()
 
-  //   app.trace('/', (req, res) => void res.end(req.method))
+    app.subscribe('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'SUBSCRIBE' })).expect(
+      'SUBSCRIBE',
+    )
+  })
+  it('app.unsubscribe handles unsubscribe request', async () => {
+    const app = new App()
 
-  //   const server = app.handler
-  //   const fetch = makeFetch(server)
+    app.unsubscribe('/', (req, res) => void res.end(req.method))
+    ;(await makeFetch(app.handler)('/', { method: 'UNSUBSCRIBE' })).expect(
+      'UNSUBSCRIBE',
+    )
+  })
+  it.skip('app.trace handles trace request', async () => {
+    const app = new App()
 
-  //   await fetch('/', { method: 'TRACE' }).expect(200, 'TRACE')
-  // })
+    app.trace('/', (req, res) => void res.end(req.method))
+    try {
+      await makeFetch(app.handler)('/', { method: 'TRACE' })
+    } catch (e) {
+      expect((e as Error).message).toBe('Method is forbidden.')
+    }
+  })
   it('HEAD request works when any of the method handlers are defined', async () => {
     const app = new App()
 
@@ -546,8 +509,7 @@ describe('HTTP methods', () => {
 
     app.get('/', (_, res) => void res.end('It works'))
 
-    const server = app.handler
-    const fetch = makeFetch(server)
+    const fetch = makeFetch(app.handler)
 
     const res = await fetch('/hello', { method: 'HEAD' })
     res.expect(404)
diff --git a/tests/modules/res.test.ts b/tests/modules/res.test.ts
index b6dedac..eacaab3 100644
--- a/tests/modules/res.test.ts
+++ b/tests/modules/res.test.ts
@@ -18,6 +18,7 @@ import {
   setVaryHeader,
 } from '../../extensions/res/mod.ts'
 import type { DummyResponse } from '../../response.ts'
+import { runServer } from '../util.test.ts'
 const __dirname = path.dirname(import.meta.url)
 
 describe('Response extensions', () => {
@@ -333,125 +334,122 @@ describe('Response extensions', () => {
       res.expect('Content-Disposition', 'attachment; filename="favicon.ico"')
     })
   })
-  // describe('res.download(filename)', () => {
-  // it('should set Content-Disposition based on path', async () => {
-  //   const app = async (req: Request) => {
-  //     const res: DummyResponse & { send?: ReturnType<typeof send> } = {
-  //       _init: {
-  //         headers: new Headers(),
-  //       },
-  //       locals: {},
-  //     }
-  //     const filePath = path.join(__dirname, '../fixtures', 'favicon.ico')
-  //     res.send = send(req, res)
-  //     await download(req, res)(filePath.slice(5, filePath.length))
-  //     return new Response(res._body, res._init)
-  //   }
-
-  //   const res = await makeFetch(app)('/')
-
-  //   res.expect('Content-Disposition', 'attachment; filename="favicon.ico"')
-  // })
-  // it('should set Content-Disposition based on filename', async () => {
-  //   const app = async (req: Request) => {
-  //     const res: DummyResponse & { send?: ReturnType<typeof send> } = {
-  //       _init: { headers: new Headers({}) },
-  //       locals: {},
-  //     }
-  //     res.send = send(req, res)
-  //     await download(req, res)(
-  //       path.join(__dirname, '../fixtures', 'favicon.ico'),
-  //       'favicon.icon',
-  //     )
-  //     return new Response(res._body, res._init)
-  //   }
-  //   const res = await makeFetch(app)('/')
-
-  //   res.expect(
-  //     'Content-Disposition',
-  //     'attachment; filename="favicon.icon"',
-  //   )
-  // })
-  // it('should pass the error to a callback', async () => {
-  //   const app = async (req: Request) => {
-  //     const res: DummyResponse & { send?: ReturnType<typeof send> } = {
-  //       _init: { headers: new Headers({}) },
-  //     }
-  //     res.send = send(req, res)
-  //     try {
-  //       await download(req, res)(
-  //         path.join(__dirname, '../fixtures'),
-  //         'some_file.png',
-  //       )
-
-  //       return new Response(res._body, res._init)
-  //     } catch (e) {
-  //       return new Response(e.message, { status: 500 })
-  //     }
-  //   }
-
-  //   const res = await makeFetch(app)('/')
-  //   res.expect(
-  //     'Content-Disposition',
-  //     'attachment; filename="some_file.png"',
-  //   )
-  // })
-  // it('should set "root" from options', async () => {
-  //   const app = runServer((req, res) => {
-  //     download(req, res)('favicon.ico', () => void 0, {
-  //       root: path.join(__dirname, '../fixtures'),
-  //     }).end()
-  //   })
-
-  //   await makeFetch(app)('/').expect(
-  //     'Content-Disposition',
-  //     'attachment; filename="favicon.ico"',
-  //   )
-  // })
-  // it(`'should pass options to sendFile'`, async () => {
-  //   const ac = new AbortController()
-  //   const app = async (req: Request) => {
-  //     const res: DummyResponse & { send?: ReturnType<typeof send> } = {
-  //       _init: { headers: new Headers({}) },
-  //       locals: {},
-  //     }
-  //     res.send = send(req, res)
-  //     await download(req, res)(
-  //       path.join(__dirname, '../fixtures', 'favicon.ico'),
-  //       'favicon.icon',
-  //       { signal: ac.signal },
-  //     )
-  //     return new Response(res._body, res._init)
-  //   }
-  //   const fetch = makeFetch(app)
-  //   const res = await fetch('/')
-  //   res.expect('Content-Disposition', 'attachment; filename="favicon.ico"')
-  // })
-  // it('should set headers from options', async () => {
-  //   const app = async (req: Request) => {
-  //     const res: DummyResponse & { send?: ReturnType<typeof send> } = {
-  //       _init: { headers: new Headers({}) },
-  //       locals: {},
-  //     }
-  //     res.send = send(req, res)
-  //     await download(req, res)(
-  //       path.join(__dirname, '../fixtures', 'favicon.ico'),
-  //       'favicon.icon',
-  //       {
-  //         headers: {
-  //           'X-Custom-Header': 'Value',
-  //         },
-  //       },
-  //     )
-  //     return new Response(res._body, res._init)
-  //   }
-  //   const fetch = makeFetch(app)
-  //   const res = await fetch('/')
-  //   res
-  //     .expect('Content-Disposition', 'attachment; filename="favicon.ico"')
-  //     .expect('X-Custom-Header', 'Value')
-  // })
-  // })
+  describe('res.download(filename)', () => {
+    it('should set Content-Disposition based on path', async () => {
+      const app = async (req: Request) => {
+        const res: DummyResponse & { send?: ReturnType<typeof send> } = {
+          _init: {
+            headers: new Headers(),
+          },
+          locals: {},
+        }
+        const filePath = path.join(Deno.cwd(), 'tests/fixtures', '/favicon.ico')
+        res.send = send(req, res)
+        await download(req, res)(filePath)
+        return new Response(res._body, res._init)
+      }
+
+      const res = await makeFetch(app)('/')
+
+      res.expect('Content-Disposition', 'attachment; filename="favicon.ico"')
+    })
+    it('should set Content-Disposition based on filename', async () => {
+      const app = async (req: Request) => {
+        const res: DummyResponse & { send?: ReturnType<typeof send> } = {
+          _init: { headers: new Headers({}) },
+          locals: {},
+        }
+        res.send = send(req, res)
+        await download(req, res)(
+          path.join(Deno.cwd(), 'tests/fixtures', '/favicon.ico'),
+          'favicon.icon',
+        )
+        return new Response(res._body, res._init)
+      }
+      const res = await makeFetch(app)('/')
+
+      res.expect(
+        'Content-Disposition',
+        'attachment; filename="favicon.icon"',
+      )
+    })
+    it('should pass the error to a callback', async () => {
+      const app = async (req: Request) => {
+        const res: DummyResponse & { send?: ReturnType<typeof send> } = {
+          _init: { headers: new Headers({}) },
+        } as DummyResponse
+        res.send = send(req, res)
+        await download(req, res)(
+          path.join(Deno.cwd(), 'tests/fixtures'),
+          'some_file.png',
+          (err) => {
+            expect((err as Error).message).toContain('readfile')
+          },
+        )
+        return new Response(res._body, res._init)
+      }
+
+      const res = await makeFetch(app)('/')
+      res.expectHeader(
+        'Content-Disposition',
+        'attachment; filename="some_file.png"',
+      )
+    })
+    it.skip('should set "root" from options', async () => {
+      const app = runServer(async (req, res) => {
+        return (await download(req, res)('favicon.ico', 'favicon.ico', {
+          root: path.join(Deno.cwd(), 'tests/fixtures'),
+        })) as unknown as Response
+      })
+      ;(await makeFetch(app)('/')).expect(
+        'Content-Disposition',
+        'attachment; filename="favicon.ico"',
+      )
+    })
+    it('should pass options to sendFile', async () => {
+      const ac = new AbortController()
+      const app = async (req: Request) => {
+        const res: DummyResponse & { send?: ReturnType<typeof send> } = {
+          _init: { headers: new Headers({}) },
+          locals: {},
+        }
+        res.send = send(req, res)
+        await download(req, res)(
+          path.join(Deno.cwd(), 'tests/fixtures', 'favicon.ico'),
+          'favicon.ico',
+          { signal: ac.signal },
+        )
+        return new Response(res._body, res._init)
+      }
+      const fetch = makeFetch(app)
+      const res = await fetch('/')
+      res.expect('Content-Disposition', 'attachment; filename="favicon.ico"')
+    })
+    it('should set headers from options', async () => {
+      const app = async (req: Request) => {
+        const res: DummyResponse & { send?: ReturnType<typeof send> } = {
+          _init: { headers: new Headers({}) },
+          locals: {},
+        }
+        res.send = send(req, res)
+        await download(req, res)(
+          path.join(Deno.cwd(), 'tests/fixtures', 'favicon.ico'),
+          'favicon.ico',
+          {
+            headers: {
+              'X-Custom-Header': 'Value',
+            },
+          },
+        )
+        return new Response(res._body, res._init)
+      }
+      const fetch = makeFetch(app)
+      const res = await fetch('/')
+      res
+        .expect('Content-Disposition', 'attachment; filename="favicon.ico"')
+        .expect('X-Custom-Header', 'Value')
+    })
+  })
   describe('res.cookie(name, value, options)', () => {
     it('serializes the cookie and puts it in a Set-Cookie header', async () => {
       const app = () => {
diff --git a/utils/eTag.ts b/utils/eTag.ts
index 02fa584..3f4ce5f 100644
--- a/utils/eTag.ts
+++ b/utils/eTag.ts
@@ -1,13 +1,13 @@
 import { base64 } from '../deps.ts'
 const encoder = new TextEncoder()
 
-const entityTag = async (entity: string): Promise<string> => {
-  if (entity.length === 0) {
+const entityTag = async (entity: string | Uint8Array): Promise<string> => {
+  if (entity.length === 0 && typeof entity != 'string') {
     // fast-path empty
     return '"0-2jmj7l5rSw0yVb/vlWAYkK/YBwk"'
   } else {
     // generate hash
-    const data = encoder.encode(entity)
+    const data = encoder.encode(entity as string)
     const buf = await crypto.subtle.digest('SHA-1', data)
     const hash = base64.encode(buf).slice(0, 27)
     const len = data.byteLength
@@ -30,8 +30,8 @@ export const eTag = async (
 
   // generate entity tag
 
-  const tag = typeof entity === 'string'
-    ? await entityTag(entity)
+  const tag = typeof entity === 'string' || ArrayBuffer.isView(entity)
+    ? await entityTag(entity as string)
     : statTag(entity)
 
   return weak ? 'W/' + tag : tag