Post 29: Implement These in an Interview — Promise Utilities

[honeycoder96]

Epic: #14
Part: VIII — Interview Corner
Series order: 29 of 30

Description

Live walkthrough of the Promise utility implementations that come up in coding interviews — from first principles, explaining the reasoning at each step.

Key topics

• Implement promisify(fn): wrap a Node-style callback API
• Implement Promise.all(promises): parallel execution, order-preserving, fail-fast
• Implement a concurrency limiter: limit(fns, concurrency)
• Implement retry(fn, attempts): with exponential backoff
• Implement a timeout wrapper: withTimeout(promise, ms)
• Interview strategy: how to approach these questions, what to talk through out loud
• Common mistakes interviewers watch for in each implementation
• Optimising for clarity: what makes an interview implementation good vs just correct