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How to Contribute

We are excited that you have decided to join us in contributing to the Zephyr Project!

Do also take the time to check our community guidelines and join in the conversations!

Learn more about our development model, development BKMs, coding conventions, etc.

Read the project documentation

Releases Overview

Updated versions of the Zephyr project are released approximately every three-months. Here are summaries for past releases.  See the Program Management wiki page for information about release planning and intermediate milestone dates.

Future Release Roadmap

Future release planning documentation is maintained in this live Zephyr Project GitHub roadmap.

While our expectations are for features to be completed in the release indicated, some features may be added to a release, moved to a different release, modified, or dropped altogether as further investigations and priorities are understood.

1.12 Release (June 2018)

  • Asymmetric multiprocessing (AMP) via integration of OpenAMP
  • Persistent storage support for Bluetooth Low Energy including Mesh
  • 802.1Q – Virtual Local Area Network (VLAN) traffic on an Ethernet network
  • Support multiple concurrent filesystem devices, partitions, and FS types
  • Ethernet network management interface
  • Networking traffic prioritization on a per-connection basis
  • Support for Ethernet statistical counters
  • Support for TAP net device on the native POSIX port
  • Command-line Zephyr meta-tool “west”
  • SPI slave support
  • Runtime non-volatile configuration data storage system (settings)

1.11 Release (March 2018)

  • Thread-level memory protection on x86, ARC and Arm, userspace and memory domains
  • Symmetric Multi-Processing (SMP) support on the Xtensa architecture.
  • Initial Armv8-M architecture support.
  • Native development environment on Microsoft Windows.
  • Native build target on POSIX platforms.
  • POSIX PSE52 partial support.
  • Thread support via integration with OpenThread.
  • Firmware over-the-air (FOTA) updates over BLE using MCUmgr.
  • Lightweight flash storage layer for constrained devices.
  • Additional SoC, platform and driver support for many of the already supported platforms.

1.10 Release (December 2017)

  • Initial alpha-quality thread-level memory protection on x86, userspace and memory domains
  • Major overhaul to the build system and a switch from Kbuild to CMake.
  • Newtron Flash Filesystem (NFFS) Support
  • Increased testsuite coverage and migrated majority of testcases to use ztest
  • Integration with MCUBOOT Bootloader
  • Additional SoC, platform and driver support for many of the already supported platforms.

1.9 Release (September 2017)

  • Bluetooth 5.0 Support (all features except Advertising Extensions)
  • Bluetooth Qualification-ready BLE Controller
  • BLE Mesh
  • Lightweight Machine-to-machine (LwM2M) support
  • Pthreads-compatible API
  • BSD Sockets-compatible API
  • MMU/MPU (continued): Thread Isolation, Paging
  • Expand Device Tree support to more architectures
  • Revamp Testsuite, increase Coverage
  • Stack Sentinal support


Zephyr project is provided as source code and build scripts for different target architectures and configurations, and not as a binary image. (See Supported Boards documentation for details.)  Updated versions of the Zephyr project are released approximately every three months. (See Release Overview for details.)

This downloads page is where you’ll find the latest tagged source code release along with its corresponding release notes found in the Zephyr Project GitHub repo and in the online release notes documentation.

Zephyr project source code is maintained in a Git repository.  For releases 1.14 and after, multiple repositories are used, so the preferred method for downloading source code is by using a Zephyr project tool called west.  While you can also download source as a tar.gz file or use Git commands (see the bottom of the GitHub release notes pages), this requires additional manual steps (see Using Zephyr without west documentation for details).

The project’s technical documentation is tagged to correspond with a specific release.  The latest documentation for the “master” branch under development can be found at Use the version selector to see the documentation for tagged versions.