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Lean 4 Proof Engineer - Mathematical Formalization

Alignerr

LLM Evaluator (Code) Contractor
Remote (Global) $10 – $40/hr May 25, 2026

Job description

Lean 4 Proof Engineer — Mathematical Formalization

About the Role

What if your deep mathematical training could directly shape the future of AI — and push the boundaries of what machines can reason about?

We're looking for mathematicians with formal verification expertise to translate rigorous human-written proofs into machine-verifiable Lean 4 formalizations. This role sits at the frontier of mathematics and computer science, working on problems that often lie beyond the reach of automated provers. You'll help map — and expand — what formal verification can express, capture, and automate.

This is a fully remote, flexible contract role designed for mathematically mature problem-solvers who find beauty in precision and satisfaction in resolving what automated tools cannot yet bridge.

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

What You'll Do

  • Translate informal mathematical proofs into Lean 4 (and related proof systems) with clarity, structure, and correctness
  • Analyze generic and domain-specific proofs to identify gaps, hidden assumptions, and formalizable sub-structures
  • Construct formalizations that test the limits of existing proof assistants — especially where current tools struggle or fail
  • Collaborate with researchers to design, refine, and evaluate strategies for improving formal verification pipelines
  • Develop readable, reproducible proof scripts aligned with mathematical best practices and proof assistant idioms
  • Provide guidance on proof decomposition, lemma selection, and structuring techniques for formal models
  • Investigate where automated provers break down and articulate precisely why — complexity, missing lemmas, insufficient libraries, and beyond
  • Formalize classical proofs and compare machine-verifiable structures against textbook arguments
  • Uncover 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 mathematics
  • Have hands-on experience with Lean (Lean 3 or Lean 4), Coq, Isabelle/HOL, Agda, or comparable formal systems — Lean 4 strongly preferred
  • Genuinely passionate about formal verification, proof assistants, and the future of mechanized mathematics
  • Able to translate informal arguments into clean, structured, machine-verifiable proofs

Nice to Have

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

Why Join Us

  • Work on genuinely frontier problems at the intersection of mathematics and AI
  • Collaborate with leading AI research teams pushing the state of the art in formal reasoning
  • Fully remote and flexible — structure your work around your life
  • Freelance autonomy with access to some of the most intellectually demanding problems in the field
  • Exposure to advanced LLMs and how formal mathematics is used to train and evaluate them
  • Potential for contract extension as new projects launch

Compensation by region

Pay varies by where you're based. Each region below is open to applicants in that country only.

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Available in 11 regions: pick your country on click.

Apply now

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