[hyamero]

What and why

Large diagrams lay out with ELK in a Node worker thread, or under Bun in a child process. Three ways that thread or process could die weren't handled:

• The thread exits without an 'error' event: the layout promise never settled, so deliver hung with no exit code, and serve stalled every later rebuild.
• The child's stdout isn't valid JSON: JSON.parse threw inside a 'close' listener, as an uncaught exception.
• The child dies before reading its input: EPIPE on its stdin was an unhandled 'error' event that crashed the process.

The thread bridge and child runner move into src/elk-io.ts. threadPort fails pending requests on 'exit', and runChild settles once and rejects on every failure path, naming the signal when the child is killed. The Bun child path now gets a real dispose that kills any leftover child. A rejected layout already becomes a clean exit 2 in the CLI. The comment on mainThreadElk now says it is Bun's large-graph host on Windows.

How it was checked

• New test/elk-io.test.ts has 8 cases, using hand-built fake threads and children:
  • exit with pending work;
  • exit after an answer;
  • an 'error' event;
  • valid JSON;
  • truncated JSON;
  • a kill by signal;
  • EPIPE on stdin;
  • settling once.
• bun run test passes (including the 500-node stress case), the Bun smoke still matches the baked layouts, and the deliver determinism smoke passes. Layout output is unchanged.

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[github-actions]

🎉 This PR is included in version 0.6.1-rc.1 🎉

The release is available on:

• v0.6.1-rc.1
• GitHub release

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[github-actions]

🎉 This PR is included in version 0.6.1 🎉

The release is available on:

• v0.6.1
• GitHub release

Your semantic-release bot 📦🚀