#mqtt #client

no-std minimq

A minimal MQTT5 client designed for no_std platforms

12 releases (6 breaking)

0.7.0 Jun 22, 2023
0.6.1 Nov 3, 2022
0.5.3 Feb 14, 2022
0.5.2 Dec 14, 2021
0.1.0 Aug 27, 2020

#76 in Embedded development

Download history 188/week @ 2023-06-03 92/week @ 2023-06-10 301/week @ 2023-06-17 156/week @ 2023-06-24 310/week @ 2023-07-01 146/week @ 2023-07-08 351/week @ 2023-07-15 788/week @ 2023-07-22 541/week @ 2023-07-29 185/week @ 2023-08-05 273/week @ 2023-08-12 198/week @ 2023-08-19 151/week @ 2023-08-26 65/week @ 2023-09-02 85/week @ 2023-09-09 40/week @ 2023-09-16

353 downloads per month
Used in 5 crates

MIT license

3.5K SLoC

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Minimq provides a minimal MQTTv5 client and message parsing for the MQTT version 5 protocol. It leverages the embedded-nal to operate on top of any TCP stack implementation and is actively used with both smoltcp and and the W5500 hardware network stack.

Minimq provides a simple, no_std interface to connect to an MQTT broker to publish messages and subscribe to topics.


Minimq supports all of the fundamental operations of MQTT, such as message subscription and publication. Below is a detailed list of features, indicating what aspects are supported:

  • Publication at all quality-of-service levels (at-most-once, at-least-once, and exactly-once)
  • Retained messages
  • Connection will messages
  • Session state reconnection and republication
  • Topic subscriptions at quality-of-service at-most-once and at-least-once
    • exactly-once subscription support is not yet implemented
  • Subscription option flags
  • Zero-copy message deserialization
  • Serde-compatible MQTT message serialization and deserialization

If there are features that you would like to have that are not yet supported, we are always accepting pull requests to extend Minimq's capabilities.

Minimq also provides convenient APIs to implement request-response interfaces over MQTT leveraging the ResponseTopic and CorrelationData properties for in-bound and out-bound messages.

Smoltcp Support

If using smoltcp, check out the smoltcp-nal to quickly create an interface that can be used by Minimq.


An example usage of Minimq that can be run on a desktop PC can be found in tests/integration_test.rs


~63K SLoC