Looking for Machine Learning work that supports AI systems? OpenTrain is the hiring organization for these roles, and candidates apply through OpenTrain. OpenTrain may place or refer successful candidates to the client whose project they will support. The work uses Machine Learning subject-matter expertise in AI-training and data-labeling tasks, with the exact scope set by each live posting.
Join OpenTrain AI to design, solve, and evaluate challenging mathematics problems that probe LLM reasoning limits; this remote, part-time contractor role expects 20+ hours/week, advanced graduate-level math knowledge, Python ability, and English fluency.
Posted Jul 20, 2026
Contract with OpenTrain as an AI Quality Analyst evaluating a conversational AI personalization feature: design multi-turn prompts, rate side-by-side text responses, and write defensible rationales. 3-month contract, remote, 20+ hrs/week with required PST overlap.
Posted Jul 17, 2026
Review and validate AI-produced C++ code for correctness, efficiency, and reliability in a remote, contractor role. Ideal for intermediate C/C++ engineers who can spend 20+ hours/week giving clear, actionable feedback to improve generated software.
Posted Jul 17, 2026
Join OpenTrain as a remote Performance Engineer focused on systems-level optimization, compiler engineering, and runtime performance for AI training data. This contract role pays $70–$110/hr and requires reliable full-time work (40 hours/week) from US-based contributors fluent in English.
Posted Jul 17, 2026
Help train frontier AI systems by designing and evaluating advanced MLOps and ML systems tasks. Apply your production expertise in JAX, PyTorch, distributed systems, and GPU kernel optimization to remote work paying $70–$110 per hour.
Posted Jul 17, 2026
Join OpenTrain AI to review and validate AI-generated Go code for dialog-agent backends in a part-time, remote contractor role (20+ hrs/week). Use your Go expertise and engineering judgment to ensure correct, efficient, and dependable implementations.
Posted Jul 17, 2026
Join OpenTrain to design and solve advanced physics problems and build evaluation benchmarks that fine-tune large language models. This remote, part-time contractor role (20+ hrs/week) suits PhD-level physicists or equivalent with strong symbolic and multi-step reasoning skills.
Posted Jul 17, 2026
Join OpenTrain AI to build evaluation datasets from public open-source code and measure how LLMs handle real-world software tasks; requires 3+ years software engineering with strong Go skills, 20+ hours/week, and eligibility in select countries.
Posted Jul 17, 2026
Join OpenTrain as a remote contractor building and evaluating LLM performance on real C++ codebases; flexible 20/30/40 hr/week schedules and opportunities to lead junior engineers. Work with researchers to design verifiable engineering tasks, triage issues, run code, and rate model outputs.
Posted Jul 17, 2026
Contractor role evaluating Spanish-language personalization for Gemini: design multi-turn prompts, rate side-by-side model outputs, and write clear, defensible rationales. 3-month engagement, remote worldwide, $15/hr, 20+ hrs/week with daily availability and a 4-hour PST overlap required.
Posted Jul 16, 2026
Join OpenTrain as a remote Machine Learning Engineer focused on benchmark-driven evaluation of real-world ML systems. This contractor role requires 3+ years of ML engineering experience, strong Python skills, and availability 20+ hrs/week with PST overlap.
Posted Jul 16, 2026
Join OpenTrain as a contractor designing and validating data pipelines and benchmark evaluation tasks for AI systems. Work part-time (20+ hrs/wk) with Python on production-like datasets; applicants need 3+ years in data engineering, data science, or data-focused software engineering.
Posted Jul 16, 2026
Write realistic multi-turn conversations that teach assistants when and how to call tools, modeling calendars, email, maps, and other app workflows. Part-time contractor role requiring 20+ hrs/week and 3+ years technical or analytical experience; open to applicants in specified countries.
Posted Jul 16, 2026
Help evaluate how AI models solve real-world software bugs by triaging GitHub issues, configuring repositories, and testing Python codebases. This part-time contractor role requires 20+ hours per week and is open in select countries.
Posted Jul 16, 2026
Build and evaluate AI systems through Python development, supervised fine-tuning, RLHF, response ranking, and public-data analysis. This fully remote contractor role offers 20, 30, or 40 hours per week for a one-month engagement.
Posted Jul 16, 2026
Join OpenTrain as a contractor producing authoritative computer‑science answers, creating golden responses, and reviewing technical solutions to improve AI. PhD required; 20+ hours/week; $80–$90/hr; fully remote and open worldwide (English).
Posted Jul 15, 2026
Design clear, unambiguous rating guidelines and rubrics for RLHF projects spanning finance, retail, insurance, legal, and sports. US-based contractors must commit to a consistent weekday schedule (min. 35 hrs/week); pay $45–$65/hr.
Posted Jul 13, 2026
Join OpenTrain as a remote Software Engineer Code Reviewer working 20+ hrs/week to write, review, and rate Go, Python, and TypeScript code to train and evaluate AI systems. Competitive contractor pay ($100–$130/hr) and flexible scheduling.
Posted Jul 10, 2026
Review AI-generated Ruby and Rails code, write clear technical explanations, and create model solutions in a remote contract role paying $55/hr for 20+ hours/week. Ideal for experienced Ruby/Rails engineers with strong writing skills and familiarity with LLM outputs.
Posted Jul 9, 2026
OpenTrain is hiring an experienced Red-Teaming QA Lead to audit adversarial prompts, safety evaluations, and trainer submissions—providing precise rubric-based feedback and improving contributor consistency. Remote, US-only contract role at $100/hr, 20+ hours/week.
Posted Jul 9, 2026
Join OpenTrain as an R Model Evaluation Engineer to review AI-generated analyses, write expert R solutions, and improve model quality. Remote contract work at $55/hr, 20+ hours/week, for experienced R users who can judge statistical correctness and explain decisions clearly.
Posted Jul 9, 2026
Remote US-based contractor role reviewing AI-generated Python ML code and workflows — $120/hr, 20+ hours/week. Evaluate correctness, spot data leakage, give clear technical feedback, and help onboard and calibrate contributor teams.
Posted Jul 9, 2026
Lead quality for Kotlin-focused AI training by reviewing AI-generated Kotlin code, coaching contributors, and keeping guidelines current — contractor role at $65/hr for 20+ hours/week. Ideal for experienced Kotlin engineers comfortable with coroutines, Android/JVM, and rubric-based evaluation.
Posted Jul 9, 2026
Join OpenTrain as a JavaScript Quality Assurance Lead to review AI-generated JavaScript, lead distributed trainers/QAs, and improve rubric-based evaluation. Part-time contractor (US-only), 20+ hrs/week at $70/hr, focused on RLHF and evaluation-rating workflows.
Posted Jul 9, 2026
Evaluate AI-generated Angular code and write model solutions as an expert Angular engineer. Remote contractor role, expert level (4+ years), ~20+ hrs/week at $90/hr — English required.
Posted Jul 9, 2026
Lead technical QA for AI-generated data science content—review code, models, metrics, and reasoning while providing clear written feedback. Remote contractor role (US only), 20+ hrs/week, top advertised pay up to $110/hr through OpenTrain.
Posted Jul 8, 2026
Contract remote role reviewing and improving AI-generated electrical engineering solutions; $40–$100/hr, 20+ hours/week. Must have hands-on EE expertise, strong written communication, and prior exposure to technical model evaluation.
Posted Jul 8, 2026
Join OpenTrain as a remote AI Data Scientist to review AI-generated analysis and code, write step-by-step reference solutions, and rate model outputs. Part-time contractor work (20+ hrs/week) with hourly pay up to $100 and hiring across many countries.
Posted Jul 8, 2026
Lead QA for Dart and Flutter code reviews, guiding contributor quality and documentation; remote US contractor role, 20+ hours/week at up to $65/hour. Evaluate AI-generated Dart code, deliver precise technical feedback, and maintain Dart-specific QA standards.
Posted Jul 8, 2026
Use your computational biology expertise to evaluate and annotate AI-generated outputs across genomics, structural biology, and systems biology. Remote contractor role, 20+ hrs/week, $40–$60/hr — help shape safer, more accurate scientific AI.
Posted Jul 7, 2026
Machine Learning expertise may be applied to preparing or reviewing examples for artificial-intelligence systems. Depending on the individual assignment, that can include writing or rating model responses, evaluating search results, reviewing code, annotating images or video, transcribing or recording audio, or translating text. The individual posting defines which activities apply and what the project asks you to do, so read it before deciding whether to explore a role.
OpenTrain is the hiring organization for roles on OpenTrain. Candidates apply through OpenTrain, and OpenTrain may place or refer successful candidates to the client whose project they will support. Hiring, eligibility, responsibilities, and other requirements are specific to each role, so use the individual live posting as the source for those details.
