Python Backend Backend Developer (Freelancing)

We are staffing a frontier AI data initiative that requires strong software engineers to build the infrastructure and training data used to develop and evaluate AI agents.

Key Responsibilities:

• The Engineer will depending on assigned track: build Python backend applications that replicate existing SaaS tools (such as Slack Linear Jira Notion Gmail and wikis) including implementing integrations and standing up full-service backend functionality;

• Perform thorough backend testing and integration validation to ensure each connector behaves faithfully like the system it emulates;

• Adapt and extend previously built connectors as needed and test existing connectors internally before they are treated as complete; Build new connectors from scratch where required within agreed delivery timeframes;

• Conduct data mining and task mining to identify representative workflows suitable for long-horizon task development; Author realistic tasks derived from mined data and workflows;

• Verify task and data quality realism and correctness through structured QA; Write clear evaluation rubrics that define correct partially correct and deficient work;

• Use AI coding agents proficiently throughout all development QA and validation work; collaborate across the connectors and tasks tracks

• Participate in onboarding calibration and quality-review cycles; deliver assigned work to the expected quality bar and on agreed milestones.

Must Have Required Skills:

• Minimum 3 years of overall experience

• Strong proficiency in Python (FastAPI Flask or Django)with proven experience in backend software development.

• Proficiency with Git Docker and basic software pipeline setup.

• Experience building scalable backend applications REST APIs and microservices.

• Proficiency in using AI coding assistants (e.g. Codex Claude Code Cursor GitHub Copilot or similar) as part of daily development workflows.

• Strong understanding of software engineering best practices including version control testing and code quality.

• Strong analytical and problem-solving skills with attention to detail.

• Ability to work independently while collaborating effectively within distributed engineering teams.

• Excellent written and verbal communication skills.

Nice to have:

• Experience building connectors or integrations for SaaS platforms.

• Knowledge of evaluation frameworks QA methodologies and rubric creation for AI datasets.

• Experience developing realistic workflows for long-horizon AI tasks.

Required Skills:

PythonDockerFast ApiFlaskDjangoAPI Integration