Handling Broken Haskell Packages in Nixpkgs Maintainer Workflow

that you can paste in a GitHub comment on the PR opened above. This comment describes which Haskell packages are now failing to build. It also pings the maintainers so that they know to fix up their packages. It may be helpful to pipe `hydra-report.hs ping-maintainers` into `xclip` (XOrg) or `wl-copy` (Wayland) in order to post on GitHub. This build report can be fetched and re-generated for new Hydra evaluations. It may help contributors to try to keep the GitHub comment updated with the most recent build report. Maintainers should be given at least 7 days to fix up their packages when they break. If maintainers don't fix up their packages within 7 days, then they may be marked broken before merging `haskell-updates` into `staging`. ### Fix Broken Packages After getting the build report, you can see which packages and Hydra jobs are failing to build. The most important jobs are the [`maintained`](https://hydra.nixos.org/job/nixpkgs/haskell-updates/maintained) and [`mergeable`](https://hydra.nixos.org/job/nixpkgs/haskell-updates/mergeable) jobs. These are both defined in [`release-haskell.nix`](../../top-level/release-haskell.nix). `mergeable` is a set of the most important Haskell packages, including things like Pandoc and XMonad. These packages are widely used. We would like to always keep these building. `maintained` is a set of Haskell packages that have maintainers in Nixpkgs. We should be proactive in working with maintainers to keep their packages building. Steps to fix Haskell packages that are failing to build is out of scope for this document, but it usually requires fixing up dependencies that are now out-of-bounds. ### Mark Broken Packages Packages that do not get fixed can be marked broken with the following commands. First check which packages are broken: ```console $ ./maintainers/scripts/haskell/hydra-report.hs get-report $ ./maintainers/scripts/haskell/hydra-report.hs mark-broken-list ``` This shows a list of packages that reported a build failure on `x86_64-linux` on Hydra. Next, run the following command: ```console $ ./maintainers/scripts/haskell/mark-broken.sh --do-commit ``` This first opens up an editor with the broken package list. Some of these packages may have a maintainer in Nixpkgs. If these maintainers have not been given 7 days to fix up their package, then make sure to remove those packages from the list before continuing. After saving and exiting the editor, the following will happen: - Packages from the list will be added to [`configuration-hackage2nix/broken.yaml`](configuration-hackage2nix/broken.yaml). This is a list of Haskell packages that are known to be broken. - [`hackage-packages.nix`](hackage-packages.nix) will be regenerated. This will mark all Haskell packages in `configuration-hackage2nix/broken.yaml` as `broken`. - The [`configuration-hackage2nix/transitive-broken.yaml`](configuration-hackage2nix/transitive-broken.yaml) file will be updated. This is a list of Haskell packages that depend on a package in `configuration-hackage2nix/broken.yaml` or `configuration-hackage2nix/transitive-broken.yaml` - `hackage-packages.nix` will be regenerated again. This will set `hydraPlatforms = none` for all the packages in `configuration-hackage2nix/transitive-broken.yaml`. This makes sure that Hydra does not try to build any of these packages. - All updated files will be committed. ## Merge `haskell-updates` into `staging` Now it is time to merge the `haskell-updates` PR you opened above. Before doing this, make sure of the following: - All Haskell packages that fail to build are correctly marked broken or transitively broken. - The `maintained` and `mergeable` jobs are passing on Hydra. - The maintainers for any maintained Haskell packages that are newly broken have been pinged on GitHub and given at least a week to fix their packages. This is especially important for widely-used packages like `cachix`.

This section details the process of addressing broken Haskell packages within the Nixpkgs `haskell-updates` workflow. After generating a build report, maintainers are notified via a GitHub comment listing failing packages, with a minimum of 7 days to fix them. Key jobs to monitor on Hydra are `maintained` (packages with assigned maintainers) and `mergeable` (critical, widely-used packages). If packages remain unfixed, they can be marked broken using a script that identifies failures, adds them to a `broken.yaml` list, regenerates `hackage-packages.nix` to mark them as `broken`, and updates `transitive-broken.yaml` to prevent Hydra from building dependent packages. The document concludes by outlining prerequisites for merging `haskell-updates` into `staging`, emphasizing that all broken packages must be correctly marked, and crucial Hydra jobs (`maintained`, `mergeable`) must be passing.