About the job
Please submit your CV in English and specify your English proficiency level.
Mindrift, in partnership with toloka-ai, connects experienced professionals with project-based work focused on testing and improving AI systems for leading technology companies. This position is a freelance, project-based role, not a permanent staff job.
Role overview
The Senior Python Developer for Functional Testing Projects will design and implement functional black box tests for large codebases across multiple programming languages. This work involves setting up and maintaining Docker environments, monitoring code coverage, and using LLMs such as Roo Code and Claude Code to streamline development. The role requires familiarity with Linux, Docker, and modern testing tools, as well as experience interpreting code in languages like C, C++, Rust, and Go with LLM support.
What you will do
- Develop functional black box tests for substantial codebases written in different programming languages.
- Configure and manage Docker environments to ensure reproducible builds and testing across platforms.
- Track code coverage and set up automated scoring criteria to meet industry standards.
- Leverage LLMs (such as Roo Code and Claude) to automate tasks, accelerate development, and enhance code quality.
Requirements
- Minimum 5 years as a Software Engineer, focusing primarily on Python.
- Extensive experience with pytest, including fixtures, session-scoped configurations, and timeouts.
- Proven skill in creating black-box functional tests for CLI tools.
- Strong expertise in Docker: writing reproducible Dockerfiles, managing user contexts, and maintaining secure workspaces.
- Advanced Linux and Bash scripting skills; comfortable debugging in containerized setups.
- Familiarity with modern Python tools (uv, pyproject.toml, packaging).
- Ability to read and understand code in C, C++, Rust, and Go, with assistance from LLMs.
- Experience using LLMs (Claude Code, Roo Code, Cursor) to automate development and generate test cases.
- English proficiency at B2 level or higher.
Preferred qualifications
- Experience with agent evaluation platforms and MCP CLI.
Tools and technologies
Python (pytest, uv, Pillow), Docker, Bash, Git Submodules, C/C++/Rust/Go (reading), Dagger, GitHub Codespaces, LLMs (Claude Code, Roo Code, Cursor), coverage.py, gcov, kcov.
Benefits and compensation
- Freelance, project-based assignments through the Mindrift platform powered by Toloka AI.
- Fully remote with flexible scheduling: set your own hours and work 20-30 hours per week.
- Compensation depends on project scope and expertise. For this project, AI trainers can earn up to $30 per hour.
Location
Remote , València, Valencian Community, Spain
