AlignerrCoding & software eval
Principal Python Engineer - ML Infrastructure
up to $75/hr
About this role, in Alignerr's words
What if your Python expertise could directly shape the infrastructure powering the next generation of AI? We're looking for a Principal Python Engineer to design and build the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on to train and improve their most advanced models.
What you'll do
- Design, build, and optimize high-performance Python systems supporting large-scale AI data pipelines and evaluation workflows
- Develop full-stack tooling and backend services for data annotation, validation, and quality control at scale
- Improve reliability, performance, and safety across existing production Python codebases
Show all 6 itemsHide the other 3 in What you'll do
- Identify and resolve bottlenecks and edge cases in data and system behavior with scalable, well-engineered fixes
- Collaborate with data, research, and engineering teams to support model training and evaluation workflows
- Participate in synchronous design reviews to drive technical strategy and architectural decisions
Candidate background
Who You Are
- Native or fluent English speaker with clear written and verbal communication skills
- 5+ years of professional experience writing production Python — specifically for large-scale infrastructure or platform engineering
- Deep expertise in designing distributed computing systems and managing concurrency with advanced asynchronous patterns
- Strong command of Python internals — GIL limitations, memory profiling, and performance optimization for compute-heavy workloads
- Full-stack development background with a strong systems programming foundation
- Experienced driving technical strategy and contributing to architectural decisions at a senior or principal level
- Able to commit 20–40 hours per week consistently
Nice to Have
Show all 4 itemsHide these 4 items in Nice to Have
- Prior experience with data annotation, data quality, or evaluation systems
- Familiarity with AI/ML workflows, model training, or benchmarking pipelines
- Background in distributed systems or developer tooling
- Experience working directly with or adjacent to AI research teams
Quoted from selected sections of Alignerr's posting. The full posting may state other conditions. Read the full posting
A closer look
More context, when you need it.
Full job descriptionThe original posting, in Alignerr's words
Posted by Alignerr, reproduced here so you can judge the role before clicking. Original posting ↗
Principal Python Engineer — ML Infrastructure (AI Training)
About the Role
What if your Python expertise could directly shape the infrastructure powering the next generation of AI? We're looking for a Principal Python Engineer to design and build the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on to train and improve their most advanced models.
This is a fully remote, flexible contract role for senior engineers who thrive on high-complexity, high-stakes infrastructure challenges. If you've spent years optimizing production Python at scale — and you want your work to matter — this is the opportunity.
- Organization: Alignerr - Type: Hourly Contract - Location: Remote - Commitment: 20–40 hours/week
What You'll Do
* Design, build, and optimize high-performance Python systems supporting large-scale AI data pipelines and evaluation workflows * Develop full-stack tooling and backend services for data annotation, validation, and quality control at scale * Improve reliability, performance, and safety across existing production Python codebases * Identify and resolve bottlenecks and edge cases in data and system behavior with scalable, well-engineered fixes * Collaborate with data, research, and engineering teams to support model training and evaluation workflows * Participate in synchronous design reviews to drive technical strategy and architectural decisions
Who You Are
* Native or fluent English speaker with clear written and verbal communication skills * 5+ years of professional experience writing production Python — specifically for large-scale infrastructure or platform engineering * Deep expertise in designing distributed computing systems and managing concurrency with advanced asynchronous patterns * Strong command of Python internals — GIL limitations, memory profiling, and performance optimization for compute-heavy workloads * Full-stack development background with a strong systems programming foundation * Experienced driving technical strategy and contributing to architectural decisions at a senior or principal level * Able to commit 20–40 hours per week consistently
Nice to Have
* Prior experience with data annotation, data quality, or evaluation systems * Familiarity with AI/ML workflows, model training, or benchmarking pipelines * Background in distributed systems or developer tooling * Experience working directly with or adjacent to AI research teams
Why Join Us
* Work on real production systems alongside the world's leading AI labs — this is infrastructure that actually ships * Fully remote and flexible — work on your own schedule from anywhere * Freelance autonomy with the depth and complexity of principal-level engineering work * Make a direct, tangible impact on how next-generation AI models are built, evaluated, and improved * Potential for ongoing work and contract extension as new projects launch
Working with AlignerrPay, getting started and work, from Alignerr's own pages
What the platform publishes in general. These are not extra terms confirmed for this particular role.
- Getting paid
- Billed weekly, Monday to Sunday, with approved work paid by the following Friday, according to Labelbox's help center. Payment goes through Stripe Connect or PayPal depending on your location, with one provider per country. intercom.help/labelbox/en/articles/13600616-alignerr-paym..., alignerr.com/process
- Before your first paid task
- Sign up, apply, verify your identity, set up billing and onboard. Some jobs add a Zara AI interview or domain assessments. alignerr.com/process
- How much work
- Time to your first project depends on demand and your skills, and there is no minimum number of hours. alignerr.com/faqs
- Contract
- Independent contractor, under terms with ALIGNERR LLC. alignerr.com/faqs, alignerr.com/privacy
Read on the pages linked above on 24 Sep 2026. Platforms change these terms, so check the linked page before you rely on one.
How does the pay compare?Across Coding & software eval roles, not this role alone
From our own daily reads of every open listing on the platforms we follow, not from Alignerr's posting. How we count.
Pay across the field: Coding & software eval
Across 391 roles in this field with a stated hourly rate in US dollars, on 14 platforms, the middle half pays $65 to $120 an hour at the top of the range, and the median is $95. This role's top rate, $75, is in the middle half. Of the 140 distinct rates we count, 44 are lower and 92 are higher.
| Platform | Roles | Top of range, per hour |
|---|---|---|
| Alignerr (this platform) | 136 | $50 to $400 · median $100 |
| micro1 | 44 | $60 to $350 · median $120 |
| Handshake AI | 43 | $47 to $125 · median $80 |
| Meridial (Invisible) | 34 | $22 to $150 · median $60 |
| Mercor | 33 | $60 to $200 · median $105 |
Sources and listing historyWhere this information comes from
This listing's history
- First seen here on 27 Aug 2026, and still on Alignerr's list when we last read it on 13 Oct 2026.
- The listed pay has not changed since then.
- Posted by Alignerr
- First seen by AIPayList
- Last seen live
- Listing ID
- 11ed577b-3aae-43ad-a823-c1fffe7e4f2d
Pay as the source states it: “$50-75/hr”.
Platforms sometimes change a rate after posting. Every listing here is re-read at least once a day and corrected when its source moves, so a difference you see on the platform is usually a change made since the last read. How freshness works.
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