Lean 4 Proof Engineer - Mathematical Formalization

Alignerr

Lean 4 Proof Engineer — Mathematical Formalization

About The Role

What if your deepest mathematical instincts could directly shape how AI understands and reasons about formal proof? We're looking for mathematicians with serious proof-writing chops to formalize advanced mathematical arguments in Lean 4 — working at the very frontier of what modern proof assistants can express, verify, and automate.

This is a fully remote, flexible contract role built for mathematicians who love precision, structure, and the challenge of translating elegant human reasoning into machine-verifiable form.

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

What You'll Do

  • Translate informal mathematical proofs into rigorous, machine-verifiable Lean 4 formalizations with an emphasis on clarity, correctness, and structure
  • Identify gaps, hidden assumptions, and formalizable sub-structures within generic and domain-specific proofs
  • Construct formalizations that probe the limits of existing proof assistants — especially where automated tools struggle or fail entirely
  • Collaborate with AI researchers to design, refine, and evaluate strategies for improving formal verification pipelines
  • Develop highly readable, reproducible proof scripts aligned with mathematical best practices and proof assistant idioms
  • Provide expert guidance on proof decomposition, lemma selection, and structuring techniques for formal models
  • Formalize classical proofs and compare machine-verifiable structures against textbook arguments
  • Investigate and articulate the breakdown points of automated provers — complexity barriers, missing lemmas, insufficient libraries, and more
  • Surface deeper patterns or generalizations implicit in the original mathematics through Lean proof construction

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 formal systems — Lean is strongly preferred
  • Genuinely excited about formal verification, proof assistants, and the future of mechanized mathematics
  • Able to translate dense, informal mathematical arguments into clean, structured formal proofs with precision and care

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 where automated reasoning frequently fails or requires significant manual scaffolding
  • Prior experience with data annotation, evaluation systems, or AI training workflows
  • Strong communication skills for articulating formalization decisions, edge cases, and reasoning strategies to non-specialist collaborators

Why Join Us

  • Work on cutting-edge AI projects alongside leading research labs and AI teams
  • Fully remote and flexible — work when and where it suits you
  • Freelance autonomy with the structure of meaningful, intellectually stimulating work
  • Get direct exposure to advanced LLMs and how they are trained on formal mathematical reasoning
  • Contribute to work that is actively pushing the boundary of what AI can understand and verify
  • Potential for ongoing work and contract extension as new projects launch