An HR system can look like a collection of CRUD screens from the outside. In practice, it is a network of business rules where attendance, leave, payroll, employee status, organizational structure, permissions, and device data influence one another.
The real challenge is the business logic
Creating an employee record is straightforward. Correctly handling joining dates, leave, attendance, fiscal years, holidays, payroll calculations, approvals, and employee status is where the system becomes significantly more complex.
Designing around business rules
Business rules should be explicit enough that another engineer can understand why a result was produced. Important calculations should not depend on assumptions hidden inside UI components or scattered API handlers.
Integrating attendance devices
External attendance devices introduce another system boundary. Employee identity mapping, duplicate events, missing mappings, webhook authentication, and synchronization failures all need to be considered when designing the integration.
Why enterprise-style applications require different thinking
The difficult part of business software is rarely the number of pages. It is maintaining consistent rules across many workflows while ensuring that changes in one part of the system do not silently break another.
