feat(prometheus-ghc-stats): add GHC RTS stats exporter package#63
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cdepillabout
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This LGTM, except that CI is failing
Add a new prometheus-ghc-stats package alongside the prometheus library. It exposes registerGHCStats, which registers a metric handle per GHC.Stats RTSStats field and returns an IO updater to refresh them on each scrape. The package is GHC2024 and uses RTSStats fields that only exist on newer compilers, so it requires GHC >= 9.10. The prometheus library keeps its full 8.10 - 9.12 matrix; a separate cabal CI job builds prometheus-ghc-stats on 9.10 and 9.12, and the 9.10 stack resolver lists both packages. prometheus-ghc-stats carries its own cabal.project so it builds against the in-tree prometheus without being pulled into the repo-root build, which would otherwise force the wider prometheus GHC matrix to solve a package it cannot build. dist-newstyle/ is added to .gitignore. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Summary
prometheus-ghc-statspackage alongside theprometheuslibrary. It exposesregisterGHCStats, which registers a metric handle perGHC.StatsRTSStatsfield and returns anIOupdater to refresh them on each scrape.GHC2024and usesRTSStatsfields that only exist on newer compilers, so it requires GHC >= 9.10. Theprometheuslibrary keeps its full 8.10–9.12 matrix; a separate cabal CI job buildsprometheus-ghc-statson 9.10 and 9.12, and the 9.10 stack resolver lists both packages.cabal.project(the repo had none) so cabal sees both packages, and addsdist-newstyle/to.gitignore.Test Plan
prometheus-ghc-statsvia cabal on GHC 9.10/9.12 and via the 9.10 stack resolver;prometheus's existing matrix is unchanged.)🤖 Generated with Claude Code