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  "path": "/t/ann-ghcup-0-2-2-0-release/14144#post_1",
  "publishedAt": "2026-05-21T17:36:46.000Z",
  "site": "https://discourse.haskell.org",
  "tags": [
    "Installer DSL",
    "https://www.haskell.org/ghcup/",
    "Asciinema video",
    "https://www.haskell.org/ghcup/guide/",
    "Adding new tools",
    "Packaging Guide",
    "141",
    "Packaging documentation",
    "documentation",
    "182",
    "60",
    "1235",
    "1312",
    "@angerman",
    "@Kleidukos",
    "@Bodigrim",
    "@Lsmor"
  ],
  "textContent": "I’m very pleased to announce the release of  **0.2.2.0**\n\n##  Motivation\n\nThe work on this release was sponsored by IOG, since their need for shipping alternative compilers coincided with the Installer DSL feature request that had been lingering on the tracker for years.\n\nWhat I ended up implementing is not quite a DSL, since I wanted to keep the complexity low, both in terms of implementation and in terms of “packaging effort” for end users.\n\nThis release is a major rewrite and took around 2 months. While I’ve been investing a lot of time in tests and correctness… there might be things that slipped through.\n\n##  How to update\n\nIf you haven’t installed yet, follow the instructions at https://www.haskell.org/ghcup/\n\nOtherwise simply run `ghcup upgrade`.\n\n##  For end users\n\n### New tools\n\nFor regular end users, I think the most exciting change is the new “3rdparty” channel, which gives access to non-core tools and compilers such as Agda, ormou, hlint, etc.\n\nAfter upgrading, add it via:\n\n\n    ghcup config add-release-channel 3rdparty\n\n\nThen run `ghcup tui` to get an overview of available tools.\n\nAsciinema video\n\n### New online documentation\n\nThe documentation uses a new readthedocs format (similar to stack) and is now structured much better: https://www.haskell.org/ghcup/guide/\n\n##  For upstream projects/packagers\n\nUpstream projects and end users can now in theory ship arbitrary tools through ghcup. Refer to the Adding new tools documentation.\n\nA lot of time has also been invested in supporting Dhall metadata. GHCup can now:\n\n  * consume metadata in the form of resolved Dhall text files (no imports, requires `.dhall` extension)\n  * consume metadata from Dhall binary format (requires `.dhallb` extension)\n  * convert an existing yaml metadata to dhall format (see `ghcup generate metadata-to-dhall`)\n  * dump the Dhall “schema” (the `GHCupInfo` type) via `ghcup generate dhall-schema`\n\n\n\nThe other major feature is _revisions_. These would allow e.g. the HLS project to add new GHC binaries to an existing release (in case that doesn’t require source code changes) without having to release a new hackage version etc. It also allows any other non source code fixes to bindists\n\nRefer to the Packaging Guide for more information.\n\n##  Full ChangeLog\n\n### New feature\n\n  * implement **“installer DSL”** (custom tool installation) wrt #141\n    * run `ghcup config add-release-channel 3rdparty` to get access to tools like `hlint`, `ormolu`, `agda` etc.\n    * refer to the Packaging documentation for more details\n    * this caused heavy changes to the internal ghcup layout and database\n  * major design change in the TUI (two-pane view)\n    * use left/right arrow keys or tab to switch between the tool and version list\n  * implement **revisions**\n    * these are “distributor” updates (e.g. fixes to bindists or the metadata) without requiring a proper upstream release\n    * refer to the documentation for more details\n  * pave the way for **OpenBSD** support wrt #182\n    * we still lack GHC bindists\n  * add experimental support for **Dhall metadata** wrt #60\n    * dump the Dhall schema via `ghcup generate dhall-schema`\n  * add `ghcup config reset` subcommand by Vladislav Sabanov\n  * add experimental healthcheck command `ghcup check tool ghc <ver>`\n    * this may only give useful information on newly installed versions since the database needs to be populated\n\n\n\n### Improvements and bug fixes\n\n  * Introduce `--verbosity=<LEVEL>` (0-2) option\n    * `--verbose` still exists and is equivalent to `--verbosity=1`\n    * ghcup won’t spam the installed file list on `--verbose`/`--verbosity=1` anymore\n  * Store log files under `XDG_STATE_HOME` instead of `XDG_CACHE_HOME` when following XDG style by Eisuke Kawashima\n  * Make `--tool` and `--show-criteria` a ‘many’ parser, fixes #1235\n  * Ignore local cache when dlUri has a `file:` scheme, fixes #1312\n  * don’t show update warnings twice (if it’s the same old warning)\n  * Fix `ghcup whereis` on windows by only using forward slashes in the output\n  * lots of other things we forgot\n\n\n\n### Breaking changes\n\n  * `cabal install <ghc-ver>` is gone, use `cabal install ghc <ghc-ver>`\n  * `cabal install-cabal <cabal-ver>` is gone, use `cabal install cabal <cabal-ver>`\n  * `ghcup compile hls --isolate=/tmp/foo` installs binaries into `/tmp/foo/bin` instead of `/tmp/foo`\n  * `ghcup list` may show `-rX` suffix on versions when there’s a revision update\n    * if you rely on version equality checks in a script and don’t want to deal with parsing those, you may consider `ghcup list --show-revisions=none`\n  * `~/.ghcup/bin/` is now all symlinks (except for `ghcup` binary itself) and the link targets may have different shape\n\n\n\n##  Contributors\n\n  * with design discussions and guidance\n    * The stable-haskell team at IOG\n    * @angerman\n  * with testing\n    * @Kleidukos\n    * @Bodigrim\n  * with reviews\n    * @Lsmor\n  * with code contributions\n    * Ai-Ya-Ya\n    * Andreas Klebinger\n    * Andreas Schacker\n    * Divam\n    * Eisuke Kawashima\n    * Jonathan Knowles\n    * Suhani370\n    * Tom Ellis\n    * Tom Smeding\n    * Vladislav Sabanov\n\n",
  "title": "[ANN] GHCup 0.2.2.0 release"
}