Mechanical Engineer & Python Expert – Freelance AI Trainer
Ethos • Remote
Education
Not stated
Type
Hourly
Pay
$75/hr
The rate in the listing.
Last checked
180d ago
Checked
About this role
From the Ethos listing
Ethos pays $75/hour for this Mechanical Engineer & Python role, a narrower cross-disciplinary bar than most STEM openings: a mechanical engineering background plus real Python fluency for simulations, data analysis, or automation. The evaluation work applies both skill sets to reviewing AI-generated engineering and technical content for correctness. It's remote and flexible, and one of the more specific technical combinations Ethos sources through referral.
Requirements
- Fluent proficiency in English (Written & Verbal)
- Reliable high-speed internet connection
- Bachelor's degree or equivalent professional experience
- Demonstrated expertise in Software Engineering
How long hiring takes
On the platforms we refer people to, half of hires came within about 25 days of applying. Time from applying to hire:
Prepare for the Ethos call
Ethos's AI interviewer asks about your AI Trainer background. These are our own practice questions for that work, not Ethos's.
How do you evaluate whether a model's response to a prompt satisfies the instruction, versus just sounding plausible?
I go back to the instruction line by line and check each requirement against the response individually, rather than reading the response holistically and asking if it feels right. A confident, well-written response can still quietly skip a constraint the prompt asked for.
What's your process for writing a rating rubric that two different reviewers would apply the same way?
I define each rating level with a concrete example rather than an abstract description, since two reviewers can read the same adjective differently but usually agree on whether a response matches a given example. I test the rubric on a handful of edge cases with another reviewer before rolling it out.
How do you decide when a prompt itself is ambiguous versus when the model's response is simply wrong?
I ask whether a reasonable person could interpret the prompt more than one way and still be following the instruction correctly. If the response fails under every reasonable reading, it's a model error; if it only fails under one specific reading, the prompt needs to be flagged as ambiguous instead.
How do you document the reasoning behind a rating so someone reviewing your work later understands the decision?
I write a short note pointing to the specific part of the response that drove the rating, so a reviewer can see what I was reacting to. A rating with no reasoning attached is hard to audit and even harder to disagree with productively.
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Common questions
How and when does Ethos pay experts?
Within 30 days of your invoice, after a project closes. Some AI training platforms pay weekly, so plan for the longer wait.
Is Ethos regular AI training work like rating chatbot responses?
No. Ethos is an expert network. AI labs, investment funds and large companies pay for your domain knowledge (deal analysis, clinical reasoning, legal logic, financial modeling) in three formats: multi-week consulting engagements, 30 to 60 minute advisory calls, and research surveys. Listings like this one are the AI-lab engagements, where you write or review expert material for a model.
What specific skills does this listing call for?
Coding and Python are named directly in the listing. If you don't have hands-on experience with these, expect the screening to test for them.
How much does this specific role pay?
This listing is posted at $75/hr, an hourly rate. Pay can change after we check the listing, so confirm the rate on the platform's application page.
What happens when I click Apply on this listing?
The link opens Ethos's sign-up. There is no form for this listing: Ethos's AI interviewer asks about your career in a 5 to 15 minute call, builds your profile from it, and then matches you to projects like this one. Keep your CV open and cover the experience the Qualifications above ask for.
Who built Ethos and is it legitimate?
Yes. Ethos was founded in London in 2024 by James Lo (McKinsey, SoftBank Vision Fund) and Daniel Mankowitz (Google DeepMind research scientist and lead author of AlphaDev). It raised a $22.75M Series A led by a16z in May 2026, with General Catalyst and XTX Markets participating, and works with AI labs, private equity firms, hedge funds and consultancies. The link on this page is an affiliate link; it doesn't affect your pay or the projects you're offered.