{"version":"2.1.238","anchor":"self-hosted-runner-prefetched-checkout-fast-path-is-compiled","canonical_anchor":"self-hosted-runner-prefetched-checkout-fast-path-is-compiled","heading":"Self-hosted runner: prefetched-checkout fast path is compiled in but inert","tier":"soon","area":"Self-Hosted Runner","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.238\/e\/self-hosted-runner-prefetched-checkout-fast-path-is-compiled","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.238","markdown":"### Self-hosted runner: prefetched-checkout fast path is compiled in but inert\n\nThe self-hosted runner has code to reuse a pre-fetched repo copy, but every clone still fetches fully.\n\n**What**\n\nThe runner gained machinery to reuse an already-fetched copy of a repository instead of cloning it: a reader for a prefetch state file, a pinned upstream ref `refs\/remotes\/prefetch\/staging`, and a function to judge whether the prefetch is fresh enough to trust. None of it runs. Every clone still does a full fetch.\n\n**Details**\n\n- The reader is called on the clone path but its body returns immediately, so the prefetched tip is never populated.\n- The eligibility function, the only thing that would weigh freshness, repo identity, worktree mode and worker epoch, has no caller anywhere in the build.\n- The git prepare function accepts the new prefetched-tip argument and never reads it; its fetch is wrapped in a build-time-true condition, so the skip-the-fetch branch is compiled out. A sibling telemetry helper returns an empty object.\n- Were it switched on, it would require the environment variable `CLAUDE_RUNNER_TRUST_CANONICAL_PREWARM` set with `--drain-grace-sec 0`, single-worker mode, and the hardcoded repository `anthropics\/anthropic`, making it an Anthropic-internal path rather than a general one.\n\n**Evidence**\n\n`canonical is not a trusted one-shot prewarm (CLAUDE_RUNNER_TRUST_CANONICAL_PREWARM unset or drain-grace > 0)`, `refs\/remotes\/prefetch\/staging`\n\n- Area: Self-Hosted Runner\n- Tier: Nothing to try yet\n- Useful: 1\/5\n- Signal: 3\/5\n- Present in the build but not switched on"}