Catch async errors

Catch async errors in JavaScript — with the four heights of help laid out: do it now, make it easier for the next person to accept, work out the right move when you are stuck, and learn the pattern so it stops coming back.

4prompt heights
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The four heights

The same task, four distances: today's deadline, the next reviewer, the stuck moment, the pattern.

Execute — do the immediate task

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I need to make sure uncaught promise rejections in the signup flow surface to Sentry and don’t…
I need to make sure uncaught promise rejections in the signup flow surface to Sentry and don’t leave the UI stuck. Wrap the async functions that run when the user clicks Create Account so the submit button is re-enabled and an error banner appears, then forward the error to Sentry, and do this before the end of today.

Improve — make it easier to accept

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Before I ship, make it obvious to a reviewer how an async failure behaves: show the user-facing…
Before I ship, make it obvious to a reviewer how an async failure behaves: show the user-facing error message first, then the retry button, and below that the telemetry call to Sentry. Highlight any places where the UI might remain blocked or state left inconsistent.

Decide — diagnose the stuck moment

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The Create Account button was clicked, the spinner started, and an uncaught rejection hit in the…

A promise rejection happened during form submit and the spinner never stopped

The Create Account button was clicked, the spinner started, and an uncaught rejection hit in the network code; now the spinner never stops and I can’t find the error in Sentry. I’m worried the button state and local store are inconsistent and I’m missing where the rejection is thrown. What’s the likely root cause and the least risky next fix to restore user experience and capture the error?

Become — change the pattern

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Across several releases we keep getting one-off crashes tied to different async handlers: WebSocket…

Occasional production crashes from uncaught async errors

Across several releases we keep getting one-off crashes tied to different async handlers: WebSocket reconnects, file uploads, and form submits. I spend time reproducing, patching, and then another slips through. What habit and guardrail should I adopt to stop these leaks, and how do I add a simple checklist so every async entry point has consistent error capture and state rollback?

Next to this one

Other programming language work people do in JavaScript.

Every task here came from the work, not from a feature list — which is why the prompts name what you want done and never the button that does it. The tool changes; the work does not.
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The rest of the map

Same library, five ways in.