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Clojure

Clojure CI on GitHub Actions

JVM startup and dependency resolution cost more than the tests.

80s → 3s
Dependency resolve

JVM startup and dependency resolution cost more than the tests.

Why it happens

~/.m2 and ~/.gitlibs are cold, and each clj invocation pays full JVM startup.

What to change

  1. Cache ~/.m2/repository and ~/.gitlibs keyed on deps.edn
  2. Run all test namespaces in one JVM rather than one per namespace
  3. Precompile with clj -T:build to avoid repeated AOT work

Clojure on runnerhut

yaml
jobs:
  test:
    runs-on: runnerhut-4vcpu-ubuntu-2404
    steps:
      - uses: actions/checkout@v4
      - uses: DeLaGuardo/setup-clojure@v13
        with: { cli: latest }
      - run: clojure -M:test
A working starting point

The only runnerhut-specific line is `runs-on: runnerhut-4vcpu-ubuntu-2404`. Everything else is standard GitHub Actions — the same actions, the same secrets and the same permissions model you use today.

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Related

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