FreeRTOS

FreeRTOS is an open-source real-time operating system kernel for microcontrollers. It provides a deterministic scheduler and a suite of inter-task communication primitives, such as queues and semaphores, to manage multitasking on resource-constrained hardware.

Project Home: There are multiple homes, see the Get Involved section for more info.

Downloads & Documentation

Fork VersionBased on Upstream VersionTargetReference SpecDownload
Codasip-V11.2.0-1.0
2026-01-28		V11.2.0
2025-03-04		riscv64cCHERI RISC-V Draft Standard 0.9.3Source
HEAD (branch)
2022-01-07		V10.4.3
2020-12-15		aarch64cUniversity of Cambridge ISAv9Source
There are no pre-built binaries or versioned releases yet, users must build from source.

Project Status

Most of the initial CHERI-FreeRTOS development took place at the University of Cambridge. While this work introduced the concept of compartmentalisation, the project hasn’t been updated in over five years and has fallen behind the official FreeRTOS releases. The concept of compartmentalisation continued on within the CHERIoT project.

The CHERI-Alliance FreeRTOS working group has recently created a new fork, focusing on a simple and clean set of patches in the hopes that they can be pushed upstream in the near future. This set of patches will focus on adding CHERI support, rather than introducing new concepts. The final touches on this are being prepared on Codasip’s GitHub repo, but will be hosted on the CHERI Alliance GitHub in the near future.

Building from Source

  • Instructions for building from source can be found in each version’s repository.

Get Involved

Development for this project happens in the following places:

There aren’t yet any regular meetings for this project

Something missing, incorrect?

This page was last updated on 3rd February 2026. Please let us know of any corrections via support@thecapablehub.org, alternatively raise a GitHub pull request in our repo.