Release Cadence and Process

Project Release Cadence

The project aims to do a release once every 6 months around April and November time and are listed in the Future release plans. The releases are to be performed and tagged on a dedicated release branch. The release process is initiated by an announcement in TF-M mailing list and followed by the creation of a release branch. Normal development on the main branch is not blocked and can be continued. The testing will be performed on release candidates and depending on issues found, additional candidates may be created to fix and retest the issues.

The Platform owners are expected to verify their platforms and confirm the correct operations or provide fixes in a timely manner to include in the release. The release notes will list all verified platforms. The platforms in Trusted Firmware OpenCI is automatically tested and any issues found shall be fixed.

After the final tag, the changes from the release branch will be back ported to main branch.

    concise "main branch" as main
    concise "release branch v1.1.x" as rel1
    concise "release branch v1.2.x" as rel2

    -3 is development
    @0 <-> @8 : release cadence: ~6 months

    0 is rc1
    main -> rel1 : start
    +1 is rc2
    +1 is v1.1.0
    +1 is {-}
    rel1 -> main : back port
    +1 is v1.1.1 #pink
    +1 is {-}
    rel1 -> main : cherry-pick
    +3 is {hidden}

    8 is rc1
    main -> rel2 : start
    +1 is v1.2.0
    +1 is {-}

    rel2 -> main : back port

    @0 <-> @3 : release process
    @4 <-> @5 : hotfix


Although this document specifies the release cadence, this does not preclude an adhoc release for specific project requirements.

Release Version Scheme

Trusted Firmware-M uses a semantic versioning scheme. A version number is compiled as a dot separated set of numbers:


  • <MAJOR>: Major release version for significant feature and API changes.

  • <MINOR>: Minor release version for incremental features and API changes.

  • <HOTFIX>: Used only for backporting critical bug fix/security patches.

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