CertProof

Project intro

CertProof makes certificates for events, then checks its own work. Describe an event, pick a style (or let the AI design one), add your branding and recipients, and it builds a print-ready PDF — then a separate verifier re-reads the actual PDF bytes and compares every page with your list, flagging a missing, repeated, cut-off or altered name before anything is printed. It also offers a blank-name mode for handwriting names later, and a checker for certificate batches made in some other tool. It is local-first and single-user: no account, no cloud database, no paid API, and recipient lists and signature images stay on your computer. A local open-weight model (Gemma 3 4B through Ollama) only proposes the design and the spreadsheet column mapping; it never sees the names, and rendering, matching and verification are deterministic code. The author built it with Claude Code, and the project has 116 tests. Honest status, from the author on 15 October 2026: built and tested on Linux (Python 3.13, Chromium 141), not yet run on Windows 11, and not yet run against a real Gemma model (the AI adapter was tested against a fake Ollama server only). Its first real user was the author's college student club, running a hackathon with more than 2,000 registered teams, who used it free for participant certificates; at the time of writing the author had not sold a copy yet.