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Lean 4 Proof Engineer - Mathematical Formalization

$170-200/hrRemoteFreelanceSTEM

About the Role

What if your deep mathematical training could directly shape the future of AI — and help machines understand the most rigorous arguments the human mind can produce?

We're looking for expert mathematicians with hands-on experience in formal proof systems to translate advanced mathematical reasoning into machine-verifiable Lean 4 code. This role sits at the frontier of what proof assistants can express, capture, and automate — and you'll be the one mapping that frontier.

This is a fully remote, flexible contract role for mathematicians who care deeply about precision, structure, and the art of formal argumentation.

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

What You'll Do

  • Translate informal mathematical proofs into clean, structured Lean 4 formalizations with an emphasis on correctness and clarity
  • Analyze proofs across domains — identifying hidden assumptions, logical gaps, and formalizable sub-structures
  • Construct formalizations that test and expose the limits of existing proof assistants
  • Collaborate with AI researchers to design and evaluate strategies for improving formal verification pipelines
  • Develop readable, reproducible proof scripts aligned with mathematical best practices and proof assistant idioms
  • Guide proof decomposition, lemma selection, and structuring techniques for formal models
  • Investigate where automated provers break down — and articulate precisely why
  • Create Lean proofs that reveal 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
  • Possess a strong foundation in rigorous proof writing across areas such as algebra, analysis, topology, logic, or discrete mathematics
  • Have hands-on experience with Lean (Lean 3 or Lean 4), Coq, Isabelle/HOL, Agda, or comparable systems — Lean 4 strongly preferred
  • Thrive at the intersection of mathematics and formal computer science
  • Take satisfaction in translating dense, elegant human arguments into forms a machine can fully verify
  • Appreciate precision, structural beauty, and the challenge of resolving gaps that automated tools cannot yet bridge

Nice to Have

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

Why Join Us

  • Work directly on cutting-edge AI research alongside leading labs and researchers
  • Fully remote and flexible — work when and where it suits you
  • Freelance autonomy with the structure of meaningful, intellectually rigorous work
  • Operate at the frontier of mechanized mathematics — pushing what formal verification can achieve
  • Potential for ongoing work and contract extension as new projects launch