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Unit Tests from Diffs

Generate missing unit tests for the code changed in a PR.

Intermediate16h1–2 people17/20 fit
TL;DR

Build Unit Tests from Diffs for developers in ~16h with 1–2 people. Stack: LLM + Node.js + Vitest.

Why it wins: Practical AI coding assistant.

Build flow

01 · Problem
Changes land without tests because writing them is tedious.
02 · Solution
Read the diff, identify changed functions and generate tests, run them and keep only passing, meaningful tests for review.
03 · Build
  1. 1Parse diff
  2. 2Generate tests
  3. 3Run them
  4. 4Suggest
04 · Demo
Change a function and get passing tests suggested.

MVP checklist

  • Diff analysis
  • Test generation
  • Run and filter
  • PR suggestion

Tech stack

TechRole
LLMLanguage model
Node.jsBackend runtime
VitestTooling

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