Alignerr · STEM & research
Lean 4 researcher formalizing math proofs for AI
Listed on Alignerr as “Applied Formal Methods Researcher (Lean 4)”
What this actually is
You design problems that stump current AI models, evaluate AI reasoning against the correct answer, write rubrics, and provide expert feedback. Often the highest-paid category because the expertise pool is small. The platform title (Applied Formal Methods Researcher (Lean 4)) reflects the rate band and the expertise required, not the day-to-day work.
Can you do this on your visa?
F-2 / F-4 / F-5 / F-6: open. E-1 to E-7: needs concurrent-employment permit. D-2 / D-4 students: S-3 permit, 20 hr/week cap. D-10 / D-8: case by case.
Korean tax on USD income
First 5 years in Korea: foreign-source income only taxed if remitted into Korea. After year 5: worldwide income. Full tax guide.
Original posting from Alignerr
Applied Formal Methods Researcher (Lean 4)
About the Role
What if your mathematical expertise could directly shape how the world's most advanced AI systems reason, verify, and understand formal logic? We're looking for Applied Formal Methods Researchers to translate rigorous mathematical arguments into machine-verifiable Lean 4 proofs - working at the absolute frontier of what proof assistants can express and automate.
This is a fully remote, flexible contract role built for mathematicians who live at the intersection of abstract reasoning and precise formalization. If you find deep satisfaction in taking a dense, elegant argument and expressing it in a form a machine can verify - this role was designed for you.
- 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 clarity, correctness, and reproducibility
- Analyze generic and domain-specific proofs to identify gaps, hidden assumptions, and formalizable sub-structures
- Construct formalizations that stress-test the limits of existing proof assistants - especially where automated tools struggle or fail
- 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 Lean idioms
- Provide expert guidance on proof decomposition, lemma selection, and structuring techniques for formal models
- Investigate automated prover breakdowns and articulate root causes - complexity gaps, missing lemmas, insufficient libraries, and more
- Create Lean proofs that surface deeper patterns or generalizations implicit in the original mathematics
Who You Are
- Holds a Master's degree or higher in Mathematics, Logic, Theoretical Computer Science, or a closely related field
- Possesses a strong foundation in rigorous proof writing across areas such as algebra, analysis, topology, logic, or discrete mathematics
- Has hands-on experience with Lean (Lean 3 or Lean 4), Coq, Isabelle/HOL, Agda, or comparable proof systems - Lean 4 strongly preferred
- Deeply enthusiastic about formal verification, proof assistants, and the future of mechanized mathematics
- Able to translate informal arguments into precise, structured formal proofs with minimal ambiguity
- Mathematically mature and energized by working at the boundary of what formal tools can currently handle
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 manual scaffolding
- Prior experience with data annotation, data quality evaluation, or AI training workflows
- Strong communication skills for explaining formalization decisions, edge cases, and proof strategies to interdisciplinary teams
Why Join Us
- Work directly on cutting-edge AI projects alongside world-leading research labs
- Fully remote and flexible - structure your hours around your life, not the other way around
- Freelance autonomy with the depth and intellectual rigor of frontier research work
- Gain exposure to advanced LLMs and the formal reasoning pipelines being built to train them
- Potential for ongoing contract extension as projects evolve and scale
Quoted from Alignerr’s public listing on 2026-06-02. We don’t edit platform copy; honest framing is in the title and the “what this actually is” block above.
More on this platform
About Alignerr
Owned by Labelbox. 450+ active roles across STEM, coding, audio, language, and general categories. Public role listings; you apply per role.
Is Alignerr legit? Our review
4.6/5 on Trustpilot, 2.2/5 on Glassdoor. Both are real. Here's what the divergence means, what the work actually is, who pays well, and how Korean tax + visa rules apply.
See all AI training jobs
Browse by category and compare across all eight platforms we cover.