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What Peek is. Peek is a network logger for Flutter with the calls shown right inside the app: requests, responses, headers and failures. Search and filters find the call you are after, and a call exports as cURL, HAR, Markdown or text.

Peek attaches to Dio, Chopper and package:http through adapters. If you use Talker, Peek takes the network logs it already keeps, without recording them twice.

How it works. Peek watches the calls without changing what they carry or how they behave: nothing is delayed, retried or rewritten. It creates no client, uses no HttpOverrides and prints nothing to the console — keep the console logger you are used to.

package:http needs a wrapper, and it passes the data through unchanged. If something goes wrong inside Peek itself, the error goes to PeekOptions.onError and the app carries on.

Inspired by Pulse. The idea of Peek is inspired by Pulse, the network logger for Apple platforms. Peek is an independent project, written from scratch for Flutter.

Quick start

With Dio, two lines where the client is built and one wherever you want a button:

final dio = Dio(BaseOptions(baseUrl: 'https://api.example.com'));
dio.interceptors.add(PeekDioInterceptor(Peek.instance));

// Later, from any widget:
showPeek(context);

With Talker, one line next to the Talker you already have — the calls its loggers see are Peek's:

final peek = Peek();
peek.attach(PeekTalkerAdapter(peek, talker: talker));
dio.interceptors.add(TalkerDioLogger(talker: talker));

showPeek(context, peek: peek);

With Chopper, one interceptor in the chain:

final client = ChopperClient(
  baseUrl: Uri.parse('https://api.example.com'),
  interceptors: [PeekChopperInterceptor(Peek.instance)],
);

showPeek(context);

With package:http, which has no interceptors, one client around the one you have:

final client = PeekHttpClient(Peek.instance, http.Client());

showPeek(context);

Prefer a floating button that is always there? Wrap the app once:

MaterialApp(
  builder: (context, child) => PeekOverlay(
    enabled: kDebugMode,
    child: child!,
  ),
);

These lines are compiled, not just quoted: they live in example, an app that makes real calls all four ways and drives every screen.

Packages

Package	What it is	Depends on
peek	The core model, store and exporters (package:peek/core.dart, pure Dart) and the Flutter UI (package:peek/peek.dart)	flutter, meta
peek_chopper	PeekChopperInterceptor: reports what a Chopper client does	peek, chopper, http
peek_dio	PeekDioInterceptor: reports what a Dio client does	peek, dio
peek_http	PeekHttpClient: reports what a package:http client does	peek, http
peek_remote	PeekRemote: streams the calls to Peek Pro on a Mac, live	peek, bonsoir, shared_preferences
peek_talker	PeekTalkerAdapter: reads what Talker logs, talker_dio_logger understood out of the box	peek, peek_dio, talker, talker_dio_logger

Configuration

Everything is set once, on the Peek instance, and applies to every adapter:

final peek = Peek(
  options: PeekOptions(
    enabled: kDebugMode,
    limits: const PeekLimits(maxEntries: 500, maxBodyBytes: 256 * 1024),
    redaction: PeekRedactionPolicy(
      headerNames: {...PeekRedactionPolicy.defaultHeaderNames, 'x-session'},
    ),
    onError: (error, stackTrace) => log('peek: $error'),
  ),
);

• enabled — pass kDebugMode to switch Peek off in release builds without touching the adapters.
• limits — how many calls are kept, how many bytes of a body, how many calls may be pinned. What a body limit costs is maxEntries of them, so raise one with the other in mind.
• redaction — nothing is masked until asked. PeekRedactionPolicy() covers the usual names (Authorization, Cookie, token, password and their relatives); each set replaces the built-in one, so extend a set by spreading the defaults back in.
• Theme — Peek brings its own look and takes only the brightness from the app. Register an override on the app's theme to change any token: ThemeData(extensions: [PeekTheme.light().copyWith(accent: Colors.teal)]).
• Strings — subclass PeekStrings, override what you translate, and pass it to showPeek(context, strings: ...).
• Sharing — Peek depends on no sharing package. Hand it a PeekShareDelegate wired to the one you use; the example shows it with share_plus. What arrives says what it is: PeekShareKind.text is a URL, a cURL command or a summary to paste, PeekShareKind.file a HAR or a session to attach. On the web there is nothing to hand over: the browser shares the text where it can and saves the file otherwise, and a delegate given there is still used instead.

Peek Pro

Peek Pro is a Mac app for watching the network logs of a phone, a simulator or an emulator in real time. On the big screen you can search the calls, follow several apps at once and save sessions to files.

To connect, add peek_remote and start it in debug builds:

if (kDebugMode) {
  peek.attach(PeekRemote(peek)..start());
}

Then pick Connect to Peek Pro in Peek's menu and enter the code the Mac app shows. The connection is set up once.

The full guide is doc/remote.md: how to set the connection up and what stays on the device. If you are building a log viewer of your own, the protocol and the .peek file format are described in doc/spec/.

Writing your own adapter

An adapter watches a logger and reports PeekEvents into a PeekSink. It needs one import — package:peek/core.dart — and about a screen of code; doc/adapters.md is the guide, from the contract to the package layout, with a checklist at the end.

Contributing

Bugs and ideas go through the issue templates; pull requests through CONTRIBUTING.md, which has the setup, the scripts and the definition of done. Security reports are private: see SECURITY.md.

License

MIT © 2026 Dmitriy Medyannik. The icon outlines come from Lucide (ISC); see NOTICE.