TempEX

Targeted at recruitment agencies with a large headcount of temporary workers moving regularly between different client work locations, HMRC allowed a dispensation for those workers to claim travel and subsistence payments added to their net pay.

I worked with former HMRC tax and legal experts to develop the business logic to ensure compliance with the HMRC dispensation and created a mobile web app using the new fangled jQuery Mobile to allow temporary workers to maintain a record of their daily transport, mileage and subsistence costs. TempEX calculated the HMRC-approved monetary value of the travel and subsistence for each worker and applied that to the worker’s net pay. Net pay is after tax and NI, which resulted in a not-insignificant tax-free uplift for workers already close to minimum wage.

Behind the scenes, the data gathered was then incorporated into the weekly payroll run, using an integration against Sage 50 Payroll. This was an interesting integration as no API existed against Sage 50 Payroll, so I had to learn that product and the payroll process itself in great detail to reverse engineer how it manipulated the data in its Access database, by direct reference to the database itself. I wrote a diff tool to run against two MDB snapshots to understand how each step in the payroll process itself affected the underlying data. During this project I learned more about the process and mechanics of Payroll and the detail of PAYE and NI calculations than any sane person should ever need to know.

Since I was writing code that directly impacted a worker’s take-home pay, I wrote masses of unit tests against HMRC supplied test cases to ensure the software functioned as expected.

In the days before Docker, this was distributed as a VirtualBox appliance and part of the service was the set up and installation of the appliance on the client’s systems, which was often upsold into a full IT support package. Lucrative extra business for a small software agency from a geek who can do it all!