Senior Python API Engineer

About OpenTrain

OpenTrain AI is the hiring and contracting organization for this role and the #1 platform for finding and building careers in AI training and data labeling. OpenTrain helps professionals discover opportunities, build a credible AI work profile, and grow their experience in a fast-moving technology field.

• Contractor and part-time engagement
• 20+ hours per week
• Open to candidates in India, Pakistan, Nigeria, Kenya, Egypt, Ghana, Bangladesh, Türkiye, Brazil, and Mexico
• English-language role

About AI Training and Backend Engineering

AI systems depend on reliable software and carefully prepared examples. Engineers supporting AI training work help build the APIs and application pipelines used to train, evaluate, and benchmark modern models, connecting production backend systems with machine learning workflows.

• Contribute to software supporting advanced AI applications
• Work alongside machine learning engineers
• Help improve the reliability, maintainability, and performance of AI application pipelines

The Role

OpenTrain is seeking a Senior Python API Engineer to build and optimize scalable backend services for advanced AI applications. You will design and maintain RESTful APIs across their full lifecycle, write production-grade Python, and help ensure that application pipelines and deployments operate smoothly.

The structured listing identifies this opportunity as entry level, while the role description requires at least eight years of professional Python development experience. Candidates should review that experience requirement carefully before applying.

• Build and optimize scalable backend services
• Support APIs used for AI training, evaluation, and benchmarking
• Work as a contractor on a part-time schedule of 20+ hours per week

What You’ll Do

You will own important parts of the backend development lifecycle, from API design through deployment. The work combines hands-on Python engineering, asynchronous programming, performance troubleshooting, collaboration with machine learning engineers, and disciplined code review.

• Design, build, and maintain scalable RESTful APIs
• Manage APIs across their full lifecycle, from design through deployment
• Implement asynchronous programming patterns
• Troubleshoot backend performance issues
• Write maintainable Python code that meets production engineering standards
• Collaborate on APIs for training, evaluation, and benchmarking
• Review code, provide constructive feedback, and merge pull requests
• Optimize application pipelines and support smooth deployments

Required Qualifications

This role calls for advanced backend engineering experience and ownership across the software development lifecycle. You should be comfortable designing scalable services, reviewing implementation risks, and maintaining dependable engineering processes.

• At least 8 years of professional Python development experience
• Hands-on RESTful API design and maintenance experience
• Experience managing complete API lifecycles
• Strong understanding of asynchronous programming
• Experience with automated testing and CI/CD pipelines
• Proficiency with Git and scalable design patterns
• Experience reviewing code and merging pull requests
• Ability to identify risks early and take ownership across the software development lifecycle
• Familiarity with NumPy and Pandas
• Bachelor’s or master’s degree in computer science, engineering, or a related field

Helpful Background

Experience with machine learning frameworks can be useful when working on AI systems and application pipelines, though it is listed as helpful rather than required.

• PyTorch experience
• TensorFlow experience

Who Should Apply

Apply if you are an experienced Python backend engineer who enjoys building dependable APIs, improving system performance, and collaborating on software that supports machine learning workflows. Strong communication in English and availability for 20+ hours per week are important for this opportunity.

• Senior Python and backend engineers
• API specialists with production lifecycle experience
• Engineers comfortable with asynchronous systems and CI/CD
• Professionals interested in contributing to AI application infrastructure

Build Your AI Engineering Career

OpenTrain gives professionals one place to build a lasting profile around AI training and data-labeling work. By documenting relevant experience and applying to roles that match your skills, you can develop a stronger portfolio in an industry shaping how state-of-the-art AI systems are built.

• Create an OpenTrain account for free
• Build a profile that highlights your technical experience
• Discover AI opportunities aligned with your skills
• Apply in minutes and continue growing your AI work portfolio