← Back to projects
$30,000/year saved
CentralHub - Polish HR & Payroll Automation
A payroll data bridge that automates contract tracking, validation, and synchronization between an internal CRM and a Polish HR & payroll system.
Role
Solo developer - design, backend, desktop UI, database integration
Timeframe
Personal product project
Impact
$30,000/year saved
PythonPyQt6SQL ServerMySQLAWS RDSREST APIpandas
Problem
The challenge
- HR and finance teams moved employee and contract data between systems by hand, which was slow and error-prone.
- A single monthly reconciliation process could consume around 40 hours of manual work.
- Manual transfers between systems created accounting mistakes that were expensive to find and fix.
Solution
What I built
- Built a desktop tool that connects verified CRM data with the payroll SQL Server workflow.
- Automated contract and employee data sync, with validation before anything is written to production systems.
- Added Polish tax and payroll calculation checks to catch inconsistencies early.
Architecture
How it works
- PyQt6 desktop client for non-technical HR and finance users.
- Python service layer for validation, transformation, and business rules using pandas.
- Integration with SQL Server (payroll) and MySQL, with AWS RDS for hosted data.
- REST API access for data exchange between components.
Results
The impact
- Reduced a ~40 hour monthly process to minutes.
- Estimated $30,000/year saved in manual labor.
- Fewer transfer errors and clearer validation before data reaches production.