House Partnership Program

01Story

The client runs a house partnership program: “Connect with a place to call home. Providing safe, secure homes to local people.” People buy into a home through a partnership and hold a share of it alongside other partners.

I started by working with the client’s CTO and lead backend engineer on a technical assessment of the platform. The domain is unforgiving: ownership shares, partner records and returns all have to reconcile, and someone looking at a number expects it to be the same number the back office sees. The interfaces had to make that math visible rather than just display it.

02Constraints

Financial data means correctness is not negotiable, and the frontend cannot be the place where a shape assumption silently drifts from the backend. The API was NestJS and evolving in parallel with the UI, so the two had to move together without either blocking the other.

Contract drift fails the build, not the balance sheet.

03What I chose

I worked the API contract from both ends rather than consuming whatever arrived — designing REST and GraphQL shapes with the backend team, then holding those shapes in strict types so a contract change surfaced as a compile error rather than a wrong figure on a dashboard.

04Outcome