Lean Proof Engineer for AI Math Formalization

Mercor; Greater London; Remote; GBP 30,000 - 60,000; Part time

Benefits offered by this job

W-2 Employment

Placement at leading AI lab

Job summary

Cincinnatus LLC is placing a Lean engineer at a leading AI lab in Greater London to help model and prove mathematics in Lean 4. You will write and review Lean proofs, formalize informal math, and contribute to evaluating model-proofs for correctness.

This part-time role requires 20–40 hours per week with W-2 employment through Cincinnatus LLC, and opportunities to work on cutting-edge AI-for-math projects within the lab.

Qualifications

• Hands-on experience writing formal proofs in Lean 4.
• Comfort with mathlib and Lean 4 tactics.
• Strong background in proof-based mathematics, theoretical CS or logic.
• Ability to turn statements and proofs into correct formal proofs checked by Lean.
• Available for at least 20 hours per week during weekdays.

Responsibilities

• Write correct Lean 4 statements and proofs that compile against mathlib.
• Formalize natural-language mathematics into precise formal statements.
• Review AI-generated Lean statements and proofs and provide clear feedback.
• Help define guidelines and rubrics for proof quality and mathlib conventions.
• Collaborate with Lean engineers and researchers to raise quality standards.

Skills

Lean 4

Mathlib

Formal proofs

Proof engineering

Lean tactics

Education

Degree in math/CS/logic

Tools

Lean 4

mathlib

Job description

Cincinnatus LLC is placing a Lean engineer at a leading AI lab in Greater London to help model and prove mathematics in Lean 4. You will write and review Lean proofs, formalize informal math, and contribute to evaluating model-proofs for correctness.

This part-time role requires 20–40 hours per week with W-2 employment through Cincinnatus LLC, and opportunities to work on cutting-edge AI-for-math projects within the lab.