Upcoming release tasks:

  • Simplify branch/version structure -- just release from master (but will keep stable tracking latest stable release plus doc updates)

  • At some point (a couple of major releases after 2.3), remove the -static version from People still using that will get an error, and we'll add a release note to switch over to instead (and note that is deprecated)

Version scheme

  • Versions with an even second component are development versions (the master branch)
  • Versions with an odd second component are stable versions (the stable branch, or in a rc/vX.Y release candidate branch for not-yet-released versions)
  • Versions with an even third component (e.g. 1.6.2 and 1.7.0) are unreleased versions
  • Versions with an odd third component (e.g. 1.6.1 or 1.7.3) and released versions
  • Pre-release unstable binaries will be released with the date as the fourth component (e.g.
  • Release candidate binaries will be released with an even third component and and odd number as the fourth component (e.g.
  • Hackage-only dependency compatibility patch releases add a fourth patchlevel component (e.g. v1.7.3.1, in the release branch)
  • All branches except release (which matches exactly the most recent release) must have an even third component (development)
  • Branches other than stable, release, and a rc/vX.Y release candidate will always have a 0 third component (e.g. 1.7.0).


  • v1.7.x series pre-release branch (v1.7 branch)
  • release candidate for first release of v1.7.x series (v1.7 branch)
  • continuing development on pre-release branch
  • second release candidate for first release of v1.7.x series (v1.7 branch)
  • 1.7.1: first release of the 1.7.x series (release branch)
  • development for second release of 1.7.x series (stable branch)
  • release candidate for second release of 1.7.x series (stable branch)
  • 1.7.3: second release of 1.7.x series (release branch)
  • first hackage-only patch of 1.7.3 (release branch)
  • second hackage-only patch of 1.7.3 (release branch)
  • 1.8.0: unstable development code (master branch)
  • pre-release snapshot of unstable version (master branch)

Pre-release checks

  • Check for any P0 and P1 issues that should be dealt with before release
  • Check for un-merged pull requests that should be merged before release
  • Ensure release and stable branches merged to master
  • Ensure CI matrices in docs (travis-complex, appveyor, azure) have current stackage snapshots and GHC versions (e.g.
  • Ensure integration tests pass on a Windows, macOS, and Linux. Do so by checking that the latest nightly build for the master branch succeeded in Azure DevOps (or kick one off manually if any significant changes were made since the last automated build).

Release preparation

  • In master branch:

    • package.yaml: bump to next release candidate version (bump second component to next odd number, ensure third component is 0, and add patchlevel 0; e.g. from 1.8.0 to
      • Check for any entries that snuck into the previous version's changes due to merges (git diff origin/stable HEAD
  • Cut a release candidate branch rc/vX.Y from master

  • In master branch:

    • package.yaml: bump version to next unstable version (next even second component with .0 third component (e.g. from 1.9.0 to 1.10.0)
    • Change the title of the existing Unreleased changes section to what will be the next final (non-RC) release (e.g. v2.1.1).
    • add new "Unreleased changes" section: ``` ## Unreleased changes

      Release notes:

      Changes since vX.Y.Z

      Major changes:

      Behavior changes:

      Other enhancements:

      Bug fixes:


  • In RC branch:

    • Review documentation for any changes that need to be made
      • Ensure all documentation pages listed in mkdocs.yaml (git diff --stat origin/stable..HEAD doc/)
      • Any new documentation pages should have the "may not be correct for the released version of Stack" warning at the top.
      • Search for old Stack version, unstable stack version, and the next "obvious" possible versions in sequence, and UNRELEASED and replace with next release version (X.Y.1, where Y is odd).
        • Do NOT update the Dockerfiles in stackage/automated/dockerfiles yet; that will come later)
        • Do NOT update templates in .github to point at the new release version yet!
      • Search for old resolvers, set to latest resolver (e.g. in doc/ where it references the "currently the latest LTS")
      • Look for any links to "latest" (latest/) documentation, replace with version tag
    • Check that for any platform entries that need to be added to (or removed from) releases.yaml,,, and doc/, and redirects.
    • package.yaml: bump to next release candidate version (bump patchlevel (fourth) component to next odd number; e.g. from to
      • Rename the “Unreleased changes” section to the same version as package.yaml, and mark it clearly as a release candidate (e.g. v1.9.0.1 (release candidate)). Remove any empty sections.
  • For first release candidate:

    • Re-do the pre-release checks (above section)
    • package.yaml: bump to first odd patchlevel version (e.g. X.Y.0.1)
    • Follow steps in Release process below tagged with [RC] to make a release candidate
  • For subsequent release candidates:

    • Re-do the pre-release checks (above section)
    • package.yaml: bump to next odd patchlevel version (e.g. X.Y.0.3)
    • Rename the "Unreleased changes" section to the new version, clearly marked as a release candidate (e.g. vX.Y.0.3 (release candidate)). Remove any empty sections.
    • Follow steps in Release process below tagged with [RC] to make a release candidate
  • For final release:

    • package.yaml: bump version to odd last component and no patchlevel (e.g. from X.Y.0.2 to X.Y.1).
    • consolidate all the RC changes into a single section for the release version
    • Follow all steps in the Release process section below.

Release process

  • Trigger the Integration Tests workflow on Github Actions for the branch you are releasing, which will build Linux, macOS, and Windows bindists. [RC]

  • Create a new draft Github release with tag and title vX.Y.Z (where X.Y.Z matches the version in package.yaml from the previous step), targeting the RC branch. In the case of a release candidate, add (RELEASE CANDIDATE) to the name field and check the This is a pre-release checkbox. [RC]

    • See previous releases for example formatting and extra info (such as link to website for install instructions).
    • For release candidates, you should skip the list of contributors and the link to the installation instructions.
    • Include the Changelog in the description.
    • Use e.g. git shortlog -s origin/release..HEAD|sed $'s/^[0-9 \t]*/* /'|grep -v azure-pipelines|LC_ALL=C sort -f to get the list of contributors.
  • On the machine you'll be releasing from, set environment variables GITHUB_AUTHORIZATION_TOKEN and STACK_RELEASE_GPG_KEY (see stack-release-script's README). [RC]

  • Upload the Azure bindists built by Azure Pipelines to the Gitlab release [RC]

  • Download the bindist artifacts from the Azure DevOps nightly pipeline build, and put the contents under _release/.
  • To sign, hash, and upload each file to Github, run:
    for x in $(ls _release/stack-X.Y.Z*|grep -v asc|grep -v sha256|grep -v upload); do
        stack "etc/scripts/release.hs" --upload-only "$x.upload" "$x.sha256.upload" "$x.asc.upload"

TODO: have Github Actions do this automatically.

  • For any GPG key used to sign an uploaded bindist, ensure that signs their key and uploads to SKS keyserver pool:

gpg --sign-key -u 0x575159689BEFB442 <OTHER-KEY-ID> gpg --send-keys <OTHER-KEY-ID>

  • Publish the Github release. [RC]

  • Push signed Git tag, matching Github release tag name, e.g.: git tag -d vX.Y.Z; git tag -s -m vX.Y.Z vX.Y.Z && git push -f origin vX.Y.Z. [RC]

  • Upload stack package to Hackage: stack upload . --pvp-bounds=lower.

    • If you get the error

    The field "build-tools" is deprecated in the Cabal specification version 2.0. Please use 'build-tool-depends' field

    then edit stack.cabal locally and change all instances of

    build-tools: hsc2hs


    build-tool-depends: hsc2hs:hsc2hs

    and try again, then discard the local changes to stack.cabal.

    Hopefully this issue will be resolved and we can remove this instruction (alternatively, we could use a verbatim field in package.yaml).

  • Reset the release branch to the released commit, e.g.: git checkout release && git merge --ff-only vX.Y.Z && git push origin release

  • Update the stable branch similarly

  • Activate version for new release tag, on, and ensure that stable documentation has updated.

  • Update /stable and /upgrade rewrite rules with the new version and sync the application in ArgoCD.

    • Test with curl -vL >/dev/null, make sure it redirects to the new version
  • In the stable or, in the case of a release candidate, rc/vX.Y branch:

    • package.yaml: bump the version number even third component (e.g. from 1.6.1 to 1.6.2) or, in the case of a release candidate even fourth component (e.g. from to [RC]

    • Add an “Unreleased changes” section (update “changes since” version):[RC]

    ``` ## Unreleased changes

    Release notes:

    Changes since vX.Y.Z

    Major changes:

    Behavior changes:

    Other enhancements:

    Bug fixes:


    • Update templates in .github to point at the new release version (X.Y.1). SKIP THIS IN RC BRANCHES.
  • Delete the RC branch (locally and on origin). E.g. git branch -d rc/vX.Y; git push origin :rc/vX.Y.

  • Merge any changes made in the RC/release/stable branches to master (be careful about version and changelog). It is best to do this by making a ci/merge-stable-to-master branch and waiting for CI to pass, then merging. If anything is complicated to merge, consider making it a PR and getting it reviewed rather than merging immediately.

  • Announce to,, mailing lists, subject ANN: stack-X.Y.Z (or ANN: stack-X.Y release candidate), containing the release description from Github. [RC]

    • For release candidates, also include a link to the Github Release ( to download it. [RC]
  • Update fpco/stack-build Docker images with new version

  • Under commercialhaskell/stackage/automated/dockerfiles, add lts-X.Y/Dockerfile (where X.Y is the latest stackage LTS version), containing (note where X.Z is the previous LTS version, and X.Y.Z is the newly released stack version)

    FROM $DOCKER_REPO:lts-X.Z ARG STACK_VERSION=X.Y.Z RUN wget -qO-$STACK_VERSION/stack-$STACK_VERSION-linux-x86_64.tar.gz | tar xz --wildcards --strip-components=1 -C /usr/local/bin '*/stack'

  • Run ./ lts-X.Y and test that the new image has the new version of Stack.

  • Run ./ --push lts-X.Y && ./ --push --small lts-X.Y to push the new image to the registry.

Build Linux static binary distribution with Nix

NOTE: We have switched back to Alpine Linux for building static binaries, done by CI. Leaving this section for future reference.

These instructions are tested on Ubuntu 16.04, but theoretically should work on any Linux distribution.

  • Install nix (tested with v2.0.4 and v2.1.2, but should work with any)

curl | sh

  • Install and authenticate cachix (first two steps at after signing up)

  • Add nh2's cache:

cachix use static-haskell-nix

NOTE: to clear cache index, use rm $HOME/.cache/nix/binary-cache-v5.sqlite* (useful if someone else uploads new stuff to the cache and you want to use it right away). The recent narinfo-cache-positive/negative-ttl options might also help.

  • Check out stack commit to be released to ~/stack-release (or elsewhere, in which case adjust following instructions)

  • rm -f ~/stack-release/*.cabal, to ensure it's regenerated

  • clone recursively (last known to work with commit 725ceb2479637b3b3ab29298a1bc0e48c54984c9)

  • in static-stack directory, run (from static-stack/

$(nix-build --no-link -A run-stack2nix-and-static-build-script --argstr stackDir ~/stack-release)

  • Run integration tests against the static binary [TODO: improve this process by adding full support in release.hs or the integration tests for testing a binary built elsewhere]

    • In ~/stack-release, run stack build --flag stack:integration-tests stack:stack-integration-test
    • Copy binary built above to place where stack build normally puts the stack binary (e.g. cp /nix/store/7vl1xvlbbqjvf864inz5vw7z2z1k4nmw-stack- /home/vagrant/stack-release/.stack-work/install/x86_64-linux/custom-snapshot-for-building-stack-with-ghc-8.2.2-PyNP5UoO8Ott/8.2.2/bin/stack; figure it out using stack exec which stack)
    • Run stack exec stack-integration-test
  • Copy the binary built above (in /nix/store/XXX-stack-X.Y.Z/bin/stack) to ~/stack-release/_release/bin/stack-X.Y.Z-linux-x86_64/stack (replace X.Y.Z with the version, and the /nix/store/* path with that output at the end of the previous command)

  • Package, sign, and upload to Github using stack's release script in the stack directory:

cd ~/stack-release stack etc/scripts/release.hs --no-test-haddocks --binary-variant=static --build-args=--dry-run upload

(adding --build-args=--dry-run ensures the binary you copied will be used rather than building a new one)

  • Download the bindist from github and double check that the stack in it is actually static (use ldd /path/to/stack) and that --version reports correctly (and not dirty).

Setting up a Windows VM for releases

These instructions are a bit rough, but has the steps to get the Windows machine set up.

Using Virtualbox

  1. Download Virtualbox VM image:

  2. Launch the VM using Virtualbox and the image downloaded

  3. Adjust settings:

    • Number of CPUs: at least half the host's
    • Memory: at least 3 GB
    • Video RAM: the minimum recommended by Virtualbox
    • Enable 3D and 2D accelerated mode (this makes programs with lots of console output much faster)
    • Enabled shared clipboard (in VM window, Devices->Shared Clipboard->Both Directions)

Now continue to the General Windows setup subsection below.

Using ESXi

  1. Download the MSEdge on Win10 VM for VMWare (Windows, Mac).
  2. Unzip the file downloaded file
  3. Upload the VMDK file to the ESXi datastore
  4. SSH into ESXi CLI and run:
    • vmkfstools -i /vmfs/volumes/datastore1/win10-msedge/MSEdge-Win10-VMWare-disk1-ORIG.vmdk /vmfs/volumes/datastore1/win10-msedge/MSEdge-Win10-VMWare-disk1.vmdk -d thin. This converts the disk to a format that is compatible with ESXi. You may have to run esxcli system module load -m multiextent first (see
    • vmkfstools -X 80G /vmfs/volumes/datastore1/win10-msedge/MSEdge-Win10-VMWare-disk1.vmdk. This makes the disk twice as large, which helps avoid running out of disk space.
  5. In the ESXi web UI:
    • Create a new VM
      • Give is 8192 MB of memory
      • Give it 4 virtual CPUs
      • Remove the default hard disk
      • Add an Existing hard disk
        • Select /datastore1/win10-msedge/MSEdge-Win10-VMWare-disk1.vmdk
    • Power on the VM
    • In Windows settings:
      • Search for "disk management"
        • Extend the partition to take the whole disk.
      • In all likelihood, you will want to search for "remote desktop" and enable remote desktop. Then you can connect to the VM using Microsoft Remote Desktop instead of using it from within the ESXi web UI.

Now continue to the General Windows setup subsection below.

General Windows setup

  1. In Settings->Update & Security->Windows Update->Advanced options:

    • Change Choose how updates are installed to Notify to schedule restart
    • Check Defer upgrades (this avoids rebooting in the middle of the stack build)
  2. In Settings->System->Power & sleep

    • Disable turning off the screen or going to sleep when plugged in
  3. Install msysgit:

  4. Install TortoiseHG:

  5. Install nsis-2.46.5-Unicode-setup.exe from

  6. Install Stack using the Windows 64-bit installer

    a. Restart any command prompts to ensure they get new %STACK_ROOT% value.

  7. Visit in Edge to ensure system has correct CA certificates

  8. Run in command prompt:

    md C:\p
    md C:\tmp
    cd /d C:\p
  9. Create C:\p\env.bat:

    SET TEMP=C:\tmp
    SET TMP=C:\tmp
    SET PATH=C:\Users\IEUser\AppData\Roaming\local\bin;"c:\Program Files\Git\usr\bin";"C:\Program Files\Microsoft SDKs\Windows\v7.1\Bin";%PATH%
  10. Run C:\p\env.bat (do this every time you open a new command prompt)

  11. stack exec -- gpg --import, and paste in the your GPG secret key (must be done using stack exec because that uses the right keyring for the embedded msys GPG; you can get the key from another machine with gpg --export-secret-keys --armor <KEY ID>)

  12. Run in command prompt (adjust the and settings):

    git config --global
    git config --global "Emanuel Borsboom"
    git config --global push.default simple
    git config --global core.autocrlf true
    git clone
    git clone -b stable --reference C:\p\stack-release stack-release
    cd stack-release
    stack install cabal-install

Setting up an ARM VM for releases

  1. Use Scaleway to start ARMv7 and ARM64 VMs.

  2. Select Ubuntu Xenial as the operating system

  3. Install the correct version of LLVM: sudo apt-get install -y llvm-3.9 (appropriate for GHC 8.2, might need different version for other GHCs)

  4. Symlink opt-3.X to opt: sudo ln -s opt-3.9 /usr/bin/opt (adjust the version if you installed a different one above)

  5. Switch to gold linker:

    update-alternatives --install "/usr/bin/ld" "ld" "/usr/bin/" 20 update-alternatives --install "/usr/bin/ld" "ld" "/usr/bin/ld.bfd" 10 update-alternatives --config ld

  6. Add swap space:

    dd if=/dev/zero of=/swapfile1 bs=1024 count=4194304 mkswap /swapfile1 swapon /swapfile1 echo '/swapfile1 none swap sw 0 0' >>/etc/fstab

  7. Install additional tools:

    apt-get update && apt-get install -y unzip gpg

  8. Import your GPG key (gpg --import and paste the private key)

  9. Git settings (adjust for your preferences/email/name)

    git config --global push.default simple git config --global "" git config --global "Emanuel Borsboom"

  10. Install build tools and dependencies packages

    sudo apt-get install -y g++ gcc libc6-dev libffi-dev libgmp-dev make xz-utils zlib1g-dev git gnupg

  11. Install clang+llvm

    NOTE: the Debian jessie llvm package does not work (executables built with it just exit with "schedule: re-entered unsafely.").

    The version of LLVM needed depends on the version of GHC you need.

    • GHC 8.2.2 (the standard for building Stack)

    wget && \ sudo tar xvf clang+llvm-3.9.1-armv7a-linux-gnueabihf.tar.xz -C /opt

    Run this now and add it to the .profile:

    export PATH="$HOME/.local/bin:/opt/clang+llvm-3.9.1-armv7a-linux-gnueabihf/bin:$PATH"

    • GHC 7.10.3

    wget && \ sudo tar xvf clang+llvm-3.5.2-armv7a-linux-gnueabihf.tar.xz -C /opt

    Run this now and add it to the .profile:

    export PATH="$HOME/.local/bin:/opt/clang+llvm-3.5.2-armv7a-linux-gnueabihf/bin:$PATH"

  12. Install Stack

    Binary: get an existing stack binary and put it in ~/.local/bin.

    From source (using cabal-install):

    wget && \ tar xvf ghc-7.10.3-armv7-deb8-linux.tar.xz && \ cd ghc-7.10.3 && \ ./configure --prefix=/opt/ghc-7.10.3 && \ sudo make install && \ cd .. export PATH="/opt/ghc-7.10.3/bin:$PATH" wget &&&&& \ tar xvf cabal-install- && \ cd cabal-install- && \ EXTRA_CONFIGURE_OPTS="" ./ && \ cd .. && \ export PATH="$HOME/.cabal/bin:$PATH" && \ cabal update

    Edit ~/.cabal/config, and set executable-stripping: False and library-stripping: False.

    cabal unpack stack && \ cd stack-* && \ cabal install && \ mv ~/.cabal/bin/stack ~/.local/bin