Lean Engineer, Formal Mathematics (Lean 4, Mathlib, Theorem Proving)
Posted 2 days ago
You'll complete your application on Mercor's career site.
About the Role
A leading artificial intelligence lab is hiring experts in formal mathematics, Lean engineering, and proof development to aid in training models for machine-checked mathematical tasks. You will focus on drafting and auditing proofs in Lean 4, converting casual mathematical ideas into rigorous formal language, and assessing the quality of AI-generated content. Your objective is to verify that proofs satisfy compiler requirements while maintaining conceptual integrity and alignment with the source problem. This role allows you to influence the advancement of AI-based mathematical reasoning through collaboration with research staff to improve model performance across topics such as analysis, algebra, logic, and number theory. This is a part-time position needing at least 20 hours weekly, with possibilities for full-time expansion for qualified individuals.
Requirements
- Demonstrable expertise in authoring formal proofs using Lean 4, supported by work on mathlib, independent projects, or Lean tool development.
- Advanced knowledge of Lean 4 tactics and the ability to efficiently utilize mathlib to locate and apply necessary lemmas.
- Formal education or research background in logic, theoretical computer science, or proof-oriented mathematics.
- Capacity to convert prose-based mathematics into verified code alongside strong written communication skills for critiquing AI output and explaining methodologies.
- Availability for a minimum of 20 hours of work during the week.
- Previous exposure to alternative proof assistants, Lean metaprogramming, or AI-for-math evaluation benchmarks is advantageous but not mandatory.
Responsibilities
- Author idiomatic Lean 4 proofs that align with current mathlib standards across diverse mathematical fields.
- Convert intricate natural-language math, such as research lemmas and competition problems, into formal statements with high accuracy.
- Examine proofs generated by AI to identify faulty logic or incorrect premises and offer detailed, actionable feedback.
- Define and uphold best practices for proof quality, statement representation, and procedural conventions through close cooperation with research teams.
Benefits & Perks
- Provides a flexible work schedule starting at 20 hours per week with the potential to scale to 40 hours.
- Functions as a W-2 employment arrangement through Cincinnatus LLC, providing full administrative support, payroll, and benefits while working embedded within a top-tier AI laboratory.
Note: This listing is summarized and paraphrased by WorkNow from a publicly posted role. For the original wording and full details, please refer to the employer's official posting.
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