{"version":"2.1.269","anchor":"bun-jit-policy-is-throttled-down-10s-after-startup","canonical_anchor":"bun-jit-policy-is-throttled-down-10s-after-startup","heading":"Bun JIT policy is throttled down 10s after startup","tier":"internal","area":"Elsewhere","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.269\/e\/bun-jit-policy-is-throttled-down-10s-after-startup","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.269","markdown":"### Bun JIT policy is throttled down 10s after startup\n\nClaude Code now throttles Bun's JIT policy 10 seconds after startup outside fast-path launches\n\n**Unclear.** What effect JIT policy 1 has on performance or behavior is not stated in the evidence.\n\n**What**\n\nOn most CLI startups (excluding the `--preload` and `--bg-spare` fast paths), Claude Code now starts a background timer that, 10 seconds after launch, calls `Bun.unsafe.setJITPolicy?.(1)`.\n\n**Why**\n\nThis is an internal runtime tuning change, likely adjusting how Bun's just-in-time compiler behaves once the code needed for startup has already run, though the finding does not specify the exact effect.\n\n- Area: Elsewhere\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5"}