CertusQS

CertusQS is a SaaS platform for the UK contractor's monthly commercial cycle, built around the contract Bill of Quantities as a single data spine. Contractor QS teams spend four to five days each month reconciling valuations, variations and payment applications across disconnected spreadsheets, risking missed Construction Act deadlines and unauditable figures. The project required a deep understanding of the domain and a meticulous approach to user experience design. We needed to build something that was not only visually stunning but also incredibly fast and reliable at scale.

CertusQS locks the BoQ at contract execution and routes every change through auditable variations, computes all money server-side in int64 pence, and schedules statutory payment notices from the contract terms rather than manual dates. A guided valuation build-up, a variation register and generated Applications for Payment share one evidence-backed audit trail, on a Next.js frontend over a Go/Gin API. Currently a V1 test build.