Holiday accrual tracker
A small system for any employer with staff who do not work the same week twice: hours in, entitlement accrued, leave deducted, carry-over applied under the rule that allows it, and a balance that is defensible on the day somebody leaves. Seven posts on the same system, one diagram at a time, with a cost breakdown and an engineering reference at the end.
- 01
A holiday accrual tracker on AWS for a few dollars a month
The whole system on one page — hours, accrual, bookings, carry-over and the leaving balance — and why irregular hours turn a simple entitlement into an unbooked liability.
- 02
What a leave year actually is, and why yours might be 46 of them
Establishing the twelve-month window an entitlement belongs to, the per-worker default that applies when no window was ever agreed, and the split between the four-week and 1.6-week pots.
- 03
Accruing holiday on irregular hours: where 12.07% comes from
The accrual calculation for irregular-hours and part-year workers: hours worked in a period, the average that covers protected absence, the rate, and one immutable ledger line per period.
- 04
Booking time off, and the three reasons a balance survives the year
The lifecycle of a leave booking from request to deduction, and the three carry-over routes — sickness, family leave and employer failure — each with its own amount and its own expiry.
- 05
What is owed on the last day, and how to be sure of it
Settling an accrual balance on termination: closing the final period, valuing the hours at the reference-period rate, the limits on recovering overtaken leave, and the evidence pack.
- 06
What the holiday accrual tracker costs
About $3 a month. One Bedrock read per worker is the only line that grows; the queue, the table, the mail and the storage are rounding errors. Plus the three ways the bill could surprise you.
- 07
Engineering reference: the holiday accrual tracker architecture
Same system, drawn purely for engineers. Service names, region, Lambda inventory, IAM scopes, the schemas and the exact model id.
Frequently asked questions
- Why can’t I just give everyone the same number of days?
- Because a day means nothing to somebody whose shifts are four hours long one week and eleven the next. For irregular-hours and part-year workers the entitlement is accrued in hours, as a percentage of the hours actually worked in each pay period.
- Where does 12.07% come from?
- It is 5.6 weeks of statutory leave divided by the 46.4 working weeks that remain once you take that leave out of the year. It is the same entitlement as everybody else’s, expressed as a rate rather than a number of days.
- Can holiday be carried into the next year?
- Some of it, in defined circumstances — sickness, family leave, or where the employer never gave a real opportunity to take it. Each route carries a different amount for a different length of time, and the difference matters when somebody leaves.
- What happens on the last day?
- Accrued and untaken leave is paid. It is one of the few payroll numbers a former employee will check, and one of the easiest to get wrong by a year of arithmetic.
- What does it cost to run?
- A few dollars a month. See part six.