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Lean 4 Proof Engineer - Mathematical Formalization

$170-200/hrRemoteFreelanceSTEM

About the Role

What if your mathematical expertise could directly shape how AI understands and reasons about formal proofs? We're looking for Lean 4 Proof Engineers to translate advanced mathematics into machine-verifiable formalizations — working at the cutting edge of AI research and formal verification.

This is a fully remote, flexible contract role for mathematicians who love precision, structural elegance, and the challenge of pushing proof assistants to their limits.

  • Organization: Alignerr
  • Type: Hourly Contract
  • Location: Remote
  • Commitment: 10–40 hours/week

What You'll Do

  • Translate informal mathematical proofs into clean, well-structured Lean 4 formalizations
  • Identify gaps, hidden assumptions, and formalizable sub-structures within complex mathematical arguments
  • Construct formalizations that test and extend the limits of existing proof assistants
  • Collaborate with AI researchers to design and refine formal verification strategies
  • Develop readable, reproducible proof scripts aligned with mathematical best practices and Lean idioms
  • Provide expert guidance on proof decomposition, lemma selection, and formal model structuring
  • Investigate where automated provers break down — and clearly articulate why
  • Create Lean proofs that surface deeper patterns or generalizations implicit in the original mathematics

Who You Are

  • Hold a Master's degree or higher in Mathematics, Logic, Theoretical Computer Science, or a closely related field
  • Have a strong foundation in rigorous proof writing across areas such as algebra, analysis, topology, logic, or discrete math
  • Have hands-on experience with Lean (Lean 3 or Lean 4), Coq, Isabelle/HOL, Agda, or comparable systems — Lean strongly preferred
  • Genuinely passionate about formal verification, proof assistants, and the future of mechanized mathematics
  • Able to take a dense, informal mathematical argument and express it in a form a machine can verify

Nice to Have

  • Familiarity with type theory, the Curry-Howard correspondence, and proof automation tools
  • Experience contributing to large-scale formalization projects such as Mathlib
  • Exposure to theorem provers in settings where automated reasoning frequently fails or requires manual scaffolding
  • Prior experience with data annotation, quality evaluation, or AI training workflows
  • Strong communication skills for explaining formalization decisions, edge cases, and proof strategies

Why Join Us

  • Work on cutting-edge AI projects alongside leading research labs
  • Fully remote and flexible — work when and where it suits you
  • Freelance autonomy with the structure of meaningful, high-impact technical work
  • Operate at the frontier of formal verification — tackling problems that automated tools can't yet solve
  • Potential for ongoing work and contract extension as new projects launch
  • Global collaboration with researchers pushing the boundaries of AI and mathematics