Upstash QStash SDK

QStash is an HTTP based messaging and scheduling solution for serverless and edge runtimes.

It is 100% built on stateless HTTP requests and designed for:

  • Serverless functions (AWS Lambda, Cloud Run, Cloud Functions ...)
  • Client side web/mobile applications
  • WebAssembly
  • and other environments where HTTP is preferred over TCP.

Status of the SDK

It is currently in beta and we are actively collecting feedback from the community. Please report any issues you encounter or feature requests in the GitHub issues or talk to us on Discord. Thank you!

How does QStash work?

QStash is the message broker between your serverless apps. You send an HTTP request to QStash, that includes a destination, a payload and optional settings. We durably store your message and will deliver it to the destination API via HTTP. In case the destination is not ready to receive the message, we will retry the message later, to guarantee at-least-once delivery.

Quick Start


dart pub add qstash_dart

Get your authorization token

Go to upstash and copy the token.

Basic Usage:

Publishing a message

import 'package:qstash_dart/qstash_dart.dart';

void main() async {
  final c = Client(
      token: '<QSTASH_TOKEN>',

  final res = await c.publishJSON(
      destination: const Destination(
        type: DestinationType.url,
        url: '',
        // or topic: "the name or id of a topic"
      body: {
        'hello': 'world',
// PublishResponse{scheduleId: null, messageId: msg_xxxxxxxxxxxxxxxx}

Receiving a message

How to receive a message depends on your http server. The Receiver.verify method should be called by you as the first step in your handler function.

import 'package:qstash_dart/qstash_dart.dart';

void main() async {
  final receiver = Receiver(
    currentSigningKey: "sig_55CLgfUo1cbmvP6kZ2Z3WU4fQ1A3",
    nextSigningKey: "sig_7E7ZLVMTgAp7hMkz9qPRHXj44xnB",

  // Validating a signature
  final isValid = await receiver.verify(
      body: 'string', // the raw request body
      signature: 'string', // The signature from the `Upstash-Signature` header


See the documentation for details.


  • Fork the repo on GitHub
  • Clone the project to your own machine
  • Commit changes to your own branch
  • Push your work back up to your fork
  • Submit a Pull request so that we can review your changes and merge


This repo is licenced under MIT.