Lab Conda Recipes

Custom conda recipes for lab-maintained software and benchmark dependencies, built with rattler-build and published to the almost-conductor channel on prefix.dev.

Recipes live here when the package isn't on conda-forge, needs a lab-specific patch, or is still experimental.

Using packages from our channel

# pixi
pixi project channel add https://prefix.dev/almost-conductor
pixi add r-anndata

# conda / mamba
conda install -c https://prefix.dev/almost-conductor r-anndata

Builds target linux-64, osx-64, osx-arm64, and win-64. Pure Python/R recipes are built noarch. See docs/PLATFORM_SUPPORT.md for details.

Adding or updating a recipe

Full guide, recipe templates, common patterns (Python/Rust/CMake/Bioconductor), and recipe-level troubleshooting are in CONTRIBUTING.md.

Quick path for a package available on PyPI / CRAN / CPAN / LuaRocks — rattler-build can scaffold the recipe.yaml for you:

mkdir -p recipes/r-fclust
rattler-build generate-recipe cran fclust > recipes/r-fclust/recipe.yaml
rattler-build build --recipe recipes/r-fclust/recipe.yaml

Review requirements, license_file, and tests before submitting — the generator gives you a starting point, not a finished recipe.

CI / publishing

GitHub Actions validates recipes on PRs and publishes to almost-conductor on merge to main. Auth uses prefix.dev Trusted Publishers (OIDC) — no API keys.

The one-time admin setup (configuring the trusted publisher, repo wiring) lives in docs/GITHUB_SETUP.md; SETUP_CHECKLIST.md is the quick start.

For local manual uploads (rare): export PREFIX_API_KEY=... then rattler-build upload prefix -c almost-conductor output/<...>.conda.

Troubleshooting

For build/recipe issues (SHA mismatch, missing deps, failed tests, etc.) see the troubleshooting section in CONTRIBUTING.md.

Package built and uploaded but not installable / not showing up. prefix.dev re-indexes asynchronously after upload, so a freshly published package may not be resolvable for a few minutes — occasionally longer under load.

1. Confirm the upload step succeeded in the Actions logs and the artifact appears on https://prefix.dev/channels/almost-conductor.
2. If it's listed but pixi add / conda install can't find it:
   • Wait 5–15 minutes and retry — indexing lag is the most common cause.
   • Clear local solver caches: pixi clean cache and/or rm -rf ~/.cache/rattler. Stale repodata.json will hide the new build.
   • Force a repodata refresh: pixi update, or pass --no-cache to conda/mamba.
3. Still missing after ~30 minutes — re-run the workflow; a partial upload may have left the channel without a valid .conda for that platform.
4. If you rebuilt with the same version and build.number, the channel may keep the older artifact. Bump build.number and re-publish.

Resources

• rattler-build docs · recipe format
• prefix.dev docs
• conda-forge recipes — examples

Maintainers

Maintained by the lab team. Open an issue, or come to the coffee-and-code meetup. Individual recipes may carry their own licenses (see about.license in each recipe.yaml).