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Software Engineer

Mechanize

San Francisco, CA · $350k a year · Posted February 18, 2026

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Pay compared with the market

This listing pays about $350,000 a year. Across 475 open software engineer listings that state pay, the middle half runs $159,500 to $238,500 and the median is $197,500. That is 77% above the median, above the middle half of those listings.

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How AI is used in this kind of work

Among software developers, AI is already used for some of the tasks. Measured exposure for software developers: 29% (some).

Share of this job’s tasks that AI is already used for at work, from real usage. It is not a forecast of job loss, and a low number means no use seen yet. Source: Anthropic Economic Index.

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Skills this job asks for

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  • Python
  • HTML

About the job

About Mechanize

Mechanize builds reinforcement learning environments that frontier AI labs use to train and evaluate their coding models. Learn more at mechanize.work http://mechanize.work.

Why the work matters

AI models have gotten good at narrow coding tasks but still fail at the complex, judgment-heavy parts of software engineering. We build the environments that expose those failures and help models improve.

What you'll do

You'll design, build, and quality-assure RL tasks. Each task is a self-contained software engineering challenge with a prompt, an environment, and an automated grader. You own the full lifecycle: ideation, grading infrastructure, running frontier models against the task, failure analysis, and iteration. At this level, we expect you to consistently produce tasks that target meaningful capability gaps in frontier models, and to develop a strong sense for what makes a task informative versus merely difficult.

You will use coding agents heavily, and a large part of the job is directing them well, evaluating their output, and knowing when they are failing in subtle ways. You may also contribute to shared infrastructure: improving our build pipeline, automating parts of QA, or building tooling for other engineers.

What makes someone good at this

Strong technical fundamentals combined with a well-calibrated intuition for AI model behavior. You need to anticipate where a model will take shortcuts, distinguish genuine capability gaps from grader issues, and understand how a model will interpret a prompt. At this level, we expect extensive familiarity with what frontier coding agents can and can't do.

Good fit if you:

- Can code in Python

- Are confident working independently at a consistent pace

- Have developed an intuition for what coding agents can and can't do

- No prior ML or AI experience required

Probably not a good fit if you:

- Want a product engineering role building features for end users

- Prefer a highly collaborative team environment with shared ownership

- Want extensive structured mentorship

This is independent, high-ownership work. You own your tasks from start to finish, with regular check-ins and feedback.

Compensation

Compensation includes a $350,000 base salary, equity, and performance bonuses. Top performers can earn more in bonuses than in base salary.

Strong performers are recognized and promoted quickly. Benefits include health, dental, vision, and life insurance.

About Mechanize. ~20 person team in San Francisco. Backed by Patrick Collison, Nat Friedman, Daniel Gross, Jeff Dean, Dwarkesh Patel, and Sholto Douglas. Featured in the New York Times https://www.nytimes.com/2025/06/11/technology/ai-mechanize-jobs.html, the Dwarkesh Podcast https://www.dwarkesh.com/p/ege-tamay and Hard Fork https://www.youtube.com/watch?v=M5Lycj5IRwQ.

Learn more about the interview process: https://www.mechanize.work/how-our-interview-process-works

Learn more about the work: https://www.mechanize.work/what-working-here-is-like