Python FastAPI Backend Developer – Ongoing Part-Time Work

We are looking for a reliable Python backend developer to provide ongoing part-time support for an established production SaaS platform.

You will work within an existing backend codebase alongside other developers, completing features, resolving bugs, improving automated tests, and submitting clean, maintainable pull requests.

Technology Stack
Python
FastAPI
Pydantic v2
SQLAlchemy
PostgreSQL or another relational database
REST APIs
Git and GitHub
Automated Python testing
Third-party API integrations
Webhooks

Responsibilities
Develop and maintain FastAPI endpoints
Implement backend features based on assigned tickets and acceptance criteria
Build reusable filtering, validation, and database-query functionality
Write and optimize SQLAlchemy queries
Troubleshoot and fix backend bugs
Work with Pydantic models and strongly typed Python code
Integrate external APIs and webhook-based services
Write unit and integration tests
Investigate failed workflows and identify root causes
Review existing code before implementing changes
Submit clear, focused, and well-tested GitHub pull requests
Communicate progress, blockers, and technical decisions clearly

Required Experience
Strong professional experience with Python backend development
Hands-on experience with FastAPI
Good knowledge of Pydantic and SQLAlchemy
Experience working with PostgreSQL or other relational databases
Ability to understand and contribute to an existing production codebase
Experience writing automated tests
Familiarity with Git, GitHub, branches, pull requests, and code reviews
Understanding of REST API design, input validation, error handling, and database transactions
Ability to work independently from Linear, Jira, or similar development tickets

Engagement Details
Ongoing part-time position
Approximately 10–20 hours per week initially
Potential for additional hours based on performance and availability
Fully remote collaboration
Some overlap with North American or European working hours is preferred

We are looking for someone who writes maintainable code and takes time to understand the existing architecture rather than applying quick fixes without considering downstream effects.

How to Apply
Please include the following in your proposal:
Your experience with FastAPI, Pydantic, and SQLAlchemy
An example of a production Python backend you have worked on
Your experience troubleshooting complex backend or database issues
Your weekly availability
Your hourly rate
Your GitHub profile or relevant code samples, where available

Please begin your proposal with the phrase “FastAPI backend” so we know you have read the complete posting.