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JavaScript to TypeScript Migration Assistant

Migrate files to TypeScript gradually with inferred types and checks.

Advanced22h1–2 people16/20 fit
TL;DR

Build JavaScript to TypeScript Migration Assistant for teams with javascript codebases in ~22h with 1–2 people. Stack: TypeScript + Tree-sitter + LLM.

Why it wins: Hard problem with a clear finish line.

Build flow

01 · Problem
Migrations stall because typing everything manually is slow.
02 · Solution
Pick files in dependency order, infer types from usage and tests, generate typed versions and verify with the compiler.
03 · Build
  1. 1Build dependency graph
  2. 2Infer types
  3. 3Generate files
  4. 4Type check
04 · Demo
Convert a module and show it compile cleanly.

MVP checklist

  • Dependency order
  • Type inference
  • Compiler check
  • Progress

Tech stack

TechRole
TypeScriptTooling
Tree-sitterCode parsing
LLMLanguage model

Reference repos

Open-source projects you can build on. Links checked 2026-10-31.

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