Software Engineer – Machine Learning (AI Training)

Who is Hiring; Warszawa; Remote; PLN 124,000 - 220,000; Full time

Job summary

Who is Hiring is seeking experienced ML engineers to evaluate AI-generated machine learning solutions. This fully remote, hourly contract role operates in Poland, with asynchronous work and no fixed hours.

You will review code written in Python with TensorFlow, PyTorch, and scikit-learn, improve quality, catch errors, and help frontier AI models get better at building and reasoning.

Qualifications

• Deep fluency in machine learning, model development, data processing and deployment.
• Experience with ML frameworks such as TensorFlow, PyTorch, or scikit-learn.
• Excellent written communication; able to explain complex ML concepts clearly.

Responsibilities

• Review and evaluate AI-generated ML code for correctness, efficiency, scalability and clarity.
• Write high-quality ML solutions for modeling, data processing, and deployment tasks.
• Craft clear, developer-friendly explanations for model decisions and code logic.

Skills

Machine learning

Async work

Independent

Strong written communication

Detail-oriented

Education

BS/MS/PhD in CS/ML

Tools

TensorFlow

PyTorch

scikit-learn

Job description

About The Role:

What if your machine learning expertise could directly influence how the most advanced AI systems in the world think, reason, and write code? We're looking for experienced ML engineers in Warsaw and across Poland to evaluate AI-generated machine learning solutions --- catching errors, improving quality, and helping frontier AI models get genuinely better at one of the hardest things they do. Poland has one of Europe's fastest-growing tech communities, and Warsaw in particular is home to a deep pool of strong engineering talent. This role is an opportunity to put that expertise to work on global AI projects without leaving your city --- or your couch. This is a fully remote, flexible contract role. Work asynchronously on your own schedule, from wherever you are. No fixed hours, no meetings --- just high-impact, expert work that matters.

Organization:

Alignerr Type: Hourly Contract Location: Remote (Poland) Commitment: Flexible, project-based

What You'll Do

• Review and evaluate AI-generated machine learning code --- including Python, TensorFlow, PyTorch, and scikit-learn --- for correctness, efficiency, scalability, and clarity
• Write high-quality ML solutions to modeling, data processing, and deployment problems across a range of difficulty levels
• Craft clear, developer-friendly explanations for model architecture decisions, code logic, and problem-solving approaches
• Identify edge cases, ambiguities, and weaknesses in problem statements, datasets, or AI-generated responses
• Help set the quality bar for how AI understands and produces machine learning code

Who You Are

• Deeply fluent in machine learning --- you know your way around model development, data preprocessing, training pipelines, and deployment
• Hands‑on experience with ML frameworks such as TensorFlow, PyTorch, or scikit‑learn
• Strong written communicator --- able to explain complex ML concepts clearly and precisely
• Detail‑oriented and rigorous --- you catch what others miss and care about getting things right
• Self‑motivated and comfortable working independently in an async environment

Nice to Have

• 3--5+ years working on machine learning projects, pipelines, or MLOps
• Experience with model evaluation, cloud deployment, or production ML systems
• Bachelor's, Master's, or PhD in Computer Science, Machine Learning, or a related field
• Background in data labeling, RLHF, or other AI training workflows
• Prior experience with code review or technical writing

Why Join Us

• Work on cutting-edge AI projects alongside leading research labs and top AI teams
• Fully remote and async --- work when and where it suits you, with no minimum hour commitments beyond project needs
• Freelance autonomy with the structure of meaningful, task-based work
• Your contributions directly improve AI models used by top research labs and enterprise teams worldwide
• High‑performing contributors take on expanded responsibilities and lead new programs
• Potential for ongoing work and contract extension as new projects launch