Python Backend Developer
Open Source Maintainer | Morepath & Django Expert | Remote Freelancer
Building robust backend systems and maintaining widely-used open-source projects
I'm a senior Python backend developer specializing in scalable web applications and RESTful APIs. As the maintainer of several prominent open-source projects including Django Mezzanine CMS and Cartridge e-commerce platform, I bring deep expertise in backend architecture, API design, and database systems.
Based in the Carpathian Mountains of Poland, I work remotely with clients worldwide. My primary focus is backend development with Python (Morepath, Flask, Django), though I'm also comfortable with frontend technologies when projects require full-stack involvement. I specialize in clean API architecture, database design, and maintainable code.
I manage my own production infrastructure with 25+ years of Linux/Debian experience, including automated deployment pipelines (git hooks, CI/CD), gunicorn/supervisord process management, nginx configuration, and PostgreSQL administration. This gives me deep understanding of the complete application lifecycle from development to production.
I've worked with clients including Lucidogen Sàrl (educational platform) and Service and Logistics Group (rail cargo system), delivering secure backend systems and complex frontend applications with permission management.
I specialize in not just building new systems, but also modernizing legacy codebases - upgrading Python versions, introducing modern tooling (pyproject.toml, type hints), implementing CI/CD, and establishing professional development workflows. I've created comprehensive type stubs for complex libraries like PonyORM, solving typing challenges that enable full IDE support.
As a maintainer of widely-used open-source projects, I contribute to the Python and web development ecosystem:
Maintainer of Mezzanine, a Django-based content management system. Mezzanine provides a flexible, powerful CMS solution built on Django.
Maintainer of Cartridge, a Django/Mezzanine-based e-commerce platform providing shopping cart and payment integration capabilities.
Maintainer of Morepath, a Python web framework with automatic URL routing and model-driven design. Created multiple extensions including more.jwtauth (JWT authentication), more.pony (PonyORM integration), and more.cerberus (validation).
Maintainer of Overmind and its ecosystem, including the core library and developer debugger. Added features enabling isolated modules with root namespaces, enhanced debugger with state machine visualization, and architected solutions for framework-agnostic components.
Created a state-based router using Overmind state machines, published as @ovtools/router on npm. Managed in a mono-repo with CI/CD pipeline (GitHub Actions), comprehensive documentation, and example applications.
Comfortable with frontend when needed, but backend is my primary focus.
Multiple Projects | 2000s - Present
Various Projects | Throughout Career
Oct 2023 - Apr 2024 | Remote
Jul 2018 - Dec 2018 | Remote
I'm actively developing commercial applications that showcase my full-stack capabilities and production-ready code:
A multi-tenant e-commerce platform where individual artists can create their own shops and sell products. Features include shop management, product listings, payment integration, and order processing. Developed comprehensive type stubs for PonyORM to enable full type checking and IDE support.
Workflow management application for car washing and servicing businesses. Handles appointment scheduling, service tracking, customer management, and business operations optimization.
Technical Approach: Both projects use RESTful APIs with clean backend-frontend separation. I specialize in Morepath (which I maintain and extend with tools like more.jwtauth, more.pony, more.cerberus), though I'm equally experienced with Flask and Django depending on project requirements.
Beyond building new applications, I specialize in modernizing legacy codebases and establishing professional development practices:
This experience helps teams rescue aging codebases, reduce technical debt, and establish sustainable development practices for long-term maintainability.
Building robust, scalable backend systems using Python and Django. RESTful API design, database architecture, and integration services.
Design and implementation of RESTful APIs with clean architecture. Experience with Morepath, Flask, and Django frameworks. Database modeling and PostgreSQL optimization.
Django application development, Mezzanine CMS customization, Cartridge e-commerce implementation, and Django consulting.
Complete application development from database design to React frontend. Specializing in backend-frontend separation with modern state management.
Backend development for applications requiring high security standards, including educational platforms, secure messaging, and data protection compliance.
Complex user permission logic, admin panels, role-based access control, and authentication systems for enterprise applications.
Upgrade aging codebases with modern tooling, CI/CD pipelines, type hints, linting, and best practices. Reduce technical debt while maintaining backwards compatibility.
Add comprehensive type hints to Python projects, create type stubs for complex libraries, implement linting and quality tools. Improve code maintainability and IDE support.
I'm available for remote freelance projects, both short-term and long-term contracts. I work with clients worldwide from my location in Poland (CEST timezone).
Contract Type: I work under "umowa o dzieło" (work-for-hire contracts) including copyright transfer, suitable for both Polish and international clients.