Leave and holiday sync for attendance records

An HR coordinator approves a vacation request in the leave management system on Monday. On Friday, when reviewing the attendance register for payroll, that approved absence still shows as a gap — an unexcused missing punch — because the leave system and the time and attendance system don't talk to each other. The coordinator adds it manually. Next week, same thing. This is what users mean when they say 'resources from a scheduled holiday or absence do not register directly in time and attendance and must be added manually each time.'

This gap exists because leave management and time tracking are often sold as separate modules by different vendors, or as separate modules within the same vendor's product where the integration was never properly built. The two systems have different data models — leave is measured in days and approved in advance; attendance is measured in punches and resolved after the fact. Connecting them requires mapping rules (does a half-day leave count as 4 hours? does a public holiday override the shift or add to it?) that are employer-specific, so vendors ship them as separate modules and leave the integration as a professional services engagement most small and mid-size employers never buy.

The downstream effect users describe goes further: the system doesn't calculate average hours worked for vacation pay purposes and defaults to 8 hours per shift even when the actual average differs. That's not a UI bug — it's a symptom of leave and attendance data living in silos. You can't calculate an average from data you're not reading.

Every payroll cycle, someone is manually cross-referencing the approved leave calendar against the attendance register to close gaps. In companies with more than 50 employees, this is a recurring 2–4 hour task that produces errors and, in jurisdictions with strict vacation pay rules, creates real compliance exposure.

What to build

Build a sync layer that reads approved leave records from common leave management exports or APIs, matches them to the corresponding attendance register gaps, auto-fills the attendance record with the correct leave type and hours based on configurable rules per leave type, and flags any mismatches for human review before payroll closes.

Where to start

Target Canadian employers first, where provincial vacation pay rules require calculating vacation pay as a percentage of actual earnings over a period rather than a flat per-day rate — making the 'defaults to 8 hours' bug a direct dollar error on every vacation payout, which creates a clear, quantifiable cost to justify switching.

The hard part

The matching logic between a leave approval (which covers a date range and a leave type) and an attendance gap (which is a missing punch on a specific day) sounds simple but breaks constantly on edge cases — half-days, shift workers whose 'day' crosses midnight, retroactive leave approvals — and getting those wrong creates payroll errors that destroy trust immediately.