Company Management System
A FastAPI HR and payroll system where the architecture is the point — six design patterns doing real work.
The problem
HR systems collect edge cases: nested departments, different pay rules, who's allowed to see what. We used design patterns to keep each of those from leaking into everything else.
What I built
- FastAPI service with role-based access control and nested departments (Composite)
- Attendance tracking and pluggable payroll strategies (Strategy)
- PDF reporting and audit logging (Observer), plus Adapter, Factory and Facade
- pytest test suite; built by a team of four
Outcome
- Six design patterns applied to concrete requirements
- Tested with pytest
Stack
- Python
- FastAPI
- pytest
- RBAC