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Verify a Bun runtime change by driving the debug binary end-to-end.
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Creates JavaScript classes using Bun's Rust bindings generator (.classes.ts). Use when implementing new JS APIs in Rust with JSC integration, prototypes, or constructors.
JSC GC reference for Bun. Use for use-after-free, JS object leaks, "collected too early", or when touching WriteBarrier, visitChildren, visitAdditionalChildren, JSRef, JSC::Strong/Weak, hasPendingActivity, ensureStillAlive, addOpaqueRoot, reportExtraMemoryAllocated, IsoSubspace, HeapAnalyzer, finalize.
Guides using bun_sys for system calls and file I/O in Rust. Use when implementing file operations, opening fds, or any syscall path instead of std::fs or libc.
Implements JavaScript classes in C++ using JavaScriptCore. Use when creating new JS classes with C++ bindings, prototypes, or constructors.
Find the top-N slowest test files in CI from a recent BuildKite run, optionally posting the results to a Slack channel as a formatted table. Use when asked to find slow CI tests, "what's making CI slow", or to post a slow-test report to Slack.
Guides writing bundler tests using itBundled/expectBundled in test/bundler/. Use when creating or modifying bundler, transpiler, or code transformation tests.
Based on SOC occupation classification
| name | verify |
| description | Verify a Bun runtime change by driving the debug binary end-to-end. |
Build and drive the debug binary directly — never bun test, never import-and-call.
bun bd --version # builds ./build/debug/bun-debug and prints its version
For any JS-visible change, run the debug binary with -e and observe stdout:
bun bd -e '<repro>' # builds, then runs; sets BUN_DEBUG_QUIET_LOGS for you
For worker/subprocess-shaped changes, spawn a subprocess (still -e) so worker teardown / event-loop-idle paths are exercised. Cross-check against node -e '<same repro>' for Node-compat changes.
BUN_DEBUG_QUIET_LOGS=1 suppresses debug-build log spam..on/.off are added by requiring worker_threads — plain new MessageChannel() ports only have addEventListener until then.