Lean 4 Proof Engineer - Mathematical Formalization

<strong>Lean 4 Proof Engineer — Mathematical Formalization<br><br></strong><strong>About The Role<br><br></strong>What if your deep mathematical training could directly shape how the world's most advanced AI systems reason about formal logic and proof? We're looking for Lean 4 Proof Engineers to translate complex, human-written mathematical arguments into precise, machine-verifiable formalizations — pushing the boundary of what modern proof assistants can express and automate.<br><br>This is a fully remote, flexible contract role built for mathematicians who live at the intersection of rigorous proof construction and formal verification.<br><br><ul><li>Organization: Alignerr</li><li>Type: Hourly Contract</li><li>Location: Remote</li><li>Commitment: 10–40 hours/week<br><br></li></ul><strong>What You'll Do<br><br></strong><ul><li>Translate informal mathematical proofs into Lean 4 (and related systems) with an emphasis on clarity, structure, and correctness</li><li>Analyze domain-specific proofs, identifying gaps, hidden assumptions, and formalizable sub-structures</li><li>Construct formalizations that stress-test the limits of existing proof assistants — especially where automation breaks down</li><li>Collaborate with AI researchers to design, refine, and evaluate formal verification strategies</li><li>Develop readable, reproducible proof scripts aligned with best mathematical practices and proof assistant idioms</li><li>Provide expert guidance on proof decomposition, lemma selection, and structuring techniques for formal models</li><li>Investigate where automated provers fail and articulate why — complexity, missing lemmas, insufficient libraries, and more</li><li>Create Lean proofs that surface deeper patterns or generalizations implicit in the original mathematics<br><br></li></ul><strong>Who You Are<br><br></strong><ul><li>Hold a Master's degree or higher in Mathematics, Logic, Theoretical Computer Science, or a closely related field</li><li>Have a strong foundation in rigorous proof writing across areas such as algebra, analysis, topology, logic, or discrete math</li><li>Have hands-on experience with Lean (Lean 3 or Lean 4), Coq, Isabelle/HOL, Agda, or comparable systems — Lean strongly preferred</li><li>Are deeply enthusiastic about formal verification, proof assistants, and the future of mechanized mathematics</li><li>Can translate dense informal arguments into clean, well-structured formal proofs with precision<br><br></li></ul><strong>Nice to Have<br><br></strong><ul><li>Familiarity with type theory, the Curry-Howard correspondence, and proof automation tools</li><li>Experience contributing to large-scale formalization projects such as mathlib</li><li>Exposure to theorem provers where automated reasoning frequently fails or requires extensive manual scaffolding</li><li>Prior experience with data annotation, evaluation systems, or AI training workflows</li><li>Strong communication skills for explaining formalization decisions, edge cases, and proof strategies to collaborators<br><br></li></ul><strong>The Ideal Candidate<br><br></strong>You're a mathematically mature problem-solver who finds genuine satisfaction in taking a dense, elegant argument and expressing it in a form a machine can verify. You appreciate structural beauty and precision — and you're energized by the challenge of resolving gaps that automated tools can't yet bridge. You're comfortable working independently, asynchronously, and at the frontier of what formal verification can do.<br><br><strong>Why Join Us<br><br></strong><ul><li>Work on cutting-edge AI projects alongside leading research labs</li><li>Fully remote and flexible — work when and where it suits you</li><li>Freelance autonomy with meaningful, intellectually demanding work</li><li>Gain rare exposure to how advanced AI systems are trained to reason formally</li><li>Contribute to work that is actively mapping the frontier of mechanized mathematics</li><li>Potential for ongoing work and contract extension as new projects launch</li></ul>

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