Postulus

AI cover letter generator — paste a job posting, get a tailored cover letter in seconds.

Note

Archived — sunset 2026. Postulus is no longer operated or maintained. The source is published as a reference / portfolio piece. Issues and PRs are not monitored.

Postulus turned a job posting (raw text or a URL) plus a candidate profile (text or an uploaded PDF résumé) into a tailored cover letter. The first paragraph was generated for free as a preview; the full letter was unlocked with a one-time Stripe payment and exportable to DOCX — no account required.

Engineering highlights

• Two-step funnel — free first-paragraph preview (Claude) → Stripe Checkout → full generation unlocked by the verified webhook.
• Job-posting URL extraction — fetch + readability parse (@mozilla/readability + jsdom) with a JobPosting heuristic.
• PDF résumé parsing — sent natively to the Anthropic API as a document input (no external OCR).
• DOCX export — generated in memory with docx.
• Multilingual output — EN / FR / ES / DE.
• Hardened Express — Helmet CSP, express-rate-limit, account-less sessions stored in SQLite (better-sqlite3).

Stack

Node.js · Express · @anthropic-ai/sdk · Stripe · better-sqlite3 · docx · helmet · express-rate-limit · @mozilla/readability + jsdom · marked · multer

Run locally

npm install
cp .env.example .env     # fill in the keys
npm start                # http://localhost:3003

SQLite databases are created under data/ at runtime (gitignored).

Configuration (.env)

Variable	Purpose
PORT	HTTP port (default 3003)
ANTHROPIC_API_KEY	Claude API key (generation)
STRIPE_SECRET_KEY	Stripe secret key (Checkout)
STRIPE_WEBHOOK_SECRET	Stripe webhook signing secret
DOMAIN	public base URL used for Stripe redirects
ALERT_URL, ALERT_HMAC_SECRET	optional internal error reporting — safe to leave empty

License

MIT © 2026 Jamal Tantaoui — built under Iris Digital.