MTS-Connect — Industrial Support Portal

A customer support portal for an international production machine building company, where the access model is the hard part: customers, distributors, regional offices and internal staff all sit at different depths of a five-level organizational hierarchy, and permissions cascade down it.

I designed and built the backend — a tRPC/Express service with Prisma over MySQL — splitting the surface into separate admin and customer API layers so that internal tooling could evolve without destabilising the customer contract. Authentication runs on AWS Cognito JWTs, with role resolution happening once per request and flowing through to every downstream resolver.

Beyond the core API, the system integrates with Redmine for issue tracking and syncs inventory from Zaico, with batch workers handling the periodic reconciliation. The whole thing is covered by Vitest and deployed to AWS Lambda through CDK.