Code RoomJavaScript to TypeScript migration
HardPrep Room Coding #4030

JavaScript to TypeScript migration

Vibe & agenticAlgorithms & data structuresSenior–Staff~22 min

You're migrating a 60-endpoint Express.js API from JavaScript to TypeScript with stricter types, and you have several AI tools available: an autonomous coding agent that can run across the repo, an inline IDE completion model, and a chat model good at one-off reasoning. Design the end-to-end workflow: which tool does which part, in what order, and exactly where the human review gates go and why.

Implement
plan_migration_batches(endpoint_sizes: list[int], max_batch_size: int) → list[int]
Examples
in[[10,10,10,10],20]out[1,2,1]
in[[5],100]out[1]
in[[3,50,3],10]out[1,1,1]
What a strong answer looks like

Treat the AI’s output as a draft to verify, not an answer to trust. Name the specific flaw and the input that triggers it, say how you’d catch it (tests, edge cases, reading critically), and how you’d re-prompt or decompose to get it right.

0:00 of about 22 min

Vibe & agentic: describe the solution in plain language (or narrate it) and the coach grades your approach.

Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.