Litmus

A web tool for F-1 international students. Paste a job listing or offer letter, confirm five extracted fields, and get a plain-English read on where that opportunity collides with your school's published CPT rules, before you invest weeks pursuing it.

Litmus is decisive about what it can compute (term dates, deadlines, hours, commute zone) and silent about what it can't. It never renders an overall "eligible / not eligible" verdict, that's a DSO's call.

Stack

Next.js (App Router) + TypeScript + Tailwind CSS v4, with a small Zustand store persisted to localStorage. No backend: extraction, the rule engine, and mock auth all run client-side. See docs/design/handoff.md for the full design spec this build follows, and docs/OPEN_QUESTIONS.md for what's still outstanding before a real launch.

Getting started

npm install
npm run dev

Open http://localhost:3000.

Project layout

• src/app — routes: / (paste), /confirm, /results, /signin, /tracker
• src/components — screen-level and shared UI components
• src/lib/rules — per-school CPT rule data and the check engine
• src/lib/extraction — doc-type detection and field extraction (regex/keyword heuristics, not an ML model)
• src/lib/store — the Zustand app store (flow state, mock auth, saved checks)

Branching

main is the release branch; develop is the integration branch. Work happens on feature/* branches opened as pull requests against develop.