Lean Engineer: Formal Math & Proof Engineering (Part-Time)

Obsidian is seeking Lean engineers and formal mathematicians to help its AI lab state and prove mathematics correctly in Lean 4. You will write and review Lean 4 proofs, formalize informal math, and assess model proofs for fidelity.

The role is a part-time commitment of 20–40 hours weekly, with placement under the Cincinnatus LLC as employer of record. This position offers an opportunity to work with researchers on math-heavy AI projects, contribute to standards for proof quality, and