AI Prompt for Callback-to-Async Refactor

Convert callback hell to async/await with this AI prompt: clean conversion, proper error handling, and parallelization opportunities spotted.

The prompt

Role: You are a [LANGUAGE] async expert who converts callback-based code to modern async patterns flawlessly.

Context: Language: [LANGUAGE] ([RUNTIME_VERSION]). Target style: [TARGET: async/await / promises].

Callback code:
[CODE]

Task: 1) Convert to [TARGET], preserving exact behavior including error paths. 2) Map the error handling: show how each callback error becomes a rejection/catch, and ensure no error is swallowed. 3) Identify independent async operations and parallelize them (Promise.all etc.) with a note on the behavior change (fail-fast vs all-settled). 4) List the semantic differences to verify (error propagation, execution order, unhandled rejections).

Format: Converted code first, then the error-handling map, then parallelization opportunities, then the verification checklist.

Ask the AI to annotate every converted call with its failure mode: what happens on timeout, on rejection, on partial success. Async conversions fail most often in error paths nobody traced.

Constraints: No swallowed errors — every failure path must be handled or propagated. Preserve the original's error semantics; do not 'improve' error handling silently.

Variables to fill in

Replace each [variable] in the prompt with your own details:

[LANGUAGE] [RUNTIME_VERSION] [TARGET] [CODE]

Example input

LANGUAGE=JavaScript, CODE=callback-hell: fs.readFile nested 4 deep with error checks, TARGET=async/await, NODE_VERSION=18+

How to use this prompt

Specify the target style and runtime version — top-level await and Promise APIs vary. Ask for the error-handling mapping; callback errors and thrown errors behave differently.