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Haskell GHC 9.0 & Stackage LTS 19


The GHC Haskell compiler will be updated from major version 8.10 to 9.0, and Haskell packages will be updated from Stackage LTS 18 to LTS 19 versions.


Current status

Detailed Description

For Fedora 37, the GHC Haskell compiler will be updated from version 8.10.5 to the latest stable 9.0.2 release (rebasing from the ghc9.0 package). Along with this, Haskell packages in Stackage (the stable Haskell source package distribution) will be updated from the versions in LTS 18 to latest LTS 19 release. Haskell packages not in Stackage will be updated to the latest appropriate version in the upstream Hackage package repository.


Benefit to Fedora

Fedora users will have the latest stable Haskell compiler release, package tools, and current Haskell packages from Stackage LTS.

GHC 9.0 is first major release of the GHC 9 series and features performance improvements, new language extension features (in particular Linear types support), and bugfixes (see the release notes linked in the Documentation section for more details).


  • Proposal owners:
    • update ghc8.10 is build against itself
    • rebase ghc to 9.0.2
    • update ghc-rpm-macros to the final version for F37
    • refresh packagings with the latest cabal-rpm release
    • update packages to latest Stackage LTS 19 versions using cabal-rpm
    • build all the packages in a Koji sidetag repo in dependency order using fbrnch
    • push the sidetag through Bodhi to Rawhide before the mass rebuild
  • Other developers: no actions should be needed

  • Policies and guidelines: N/A (not needed for this Change)
  • Trademark approval: N/A (not needed for this Change)
  • Alignment with Objectives:

Upgrade/compatibility impact

Any dropped packages will have obsoletes added. Otherwise there should not be any direct upgrade impact.

Users' Haskell projects will get built with ghc-9.0 when they next build them and might need some minor code tweaks.

How To Test

  • install ghc and cabal-install
  • install pandoc, ShellCheck, ghcid, git-annex, hadolint, stack, xmonad
  • install ghc-*-devel or ghc-*-prof or ghc-*-doc
  • cabal-rpm builddep <favouritepackage>; cabal install <favouritepackage>
  • test upgrades of F36 Haskell packages to F37

User Experience

Users will have the most recent stable major version of ghc and Haskell libraries and tools available to them. This makes it easier to build the latest versions of Haskell projects.

In particular cabal-install will also be updated from 3.2 to 3.4.


Contingency Plan

  • Contingency mechanism: (What to do? Who will do it?)
    • Change owner will drop the new builds and revert back to the versions in F36.
  • Contingency deadline: Beta Freeze
  • Contingency mechanism: (What to do? Who will do it?) N/A (not a System Wide Change)
  • Contingency deadline: N/A (not a System Wide Change)
  • Blocks release? N/A (not a System Wide Change), Yes/No


Release Notes

The Haskell GHC compiler has been updated from 8.10.5 to 9.0.2 with many improvements.