Internship · Engineering
Backend Developer Intern
Build the APIs behind a real construction product in NestJS and PostgreSQL: forecasting maths, a change-order approval flow, and one public endpoint that has to be right.
- Location
- Remote, 4 hours of overlap with 11:00 to 19:00 Pakistan time
- Hours
- 20 or 40 hours a week
- Length
- 8 weeks, fixed cohort start
- Compensation
- Unpaid. If your work ships to a client or into our own products, we pay you for it
- Applications close
- 31 October 2026
- Stack
- TypeScriptNestJSPrismaPostgreSQLZodJest
About the role
You join a cohort of nine interns building Stage 2 of SiteDay, our field production software for sitework contractors. You own the API: budget forecasting maths, the change-order state machine, and the approval endpoint a contractor's client calls without ever logging in. The eight weeks run in three phases: weeks 1 and 2 you learn the codebase and help write the specification, weeks 3 to 6 you build your slice in parallel with the other tracks, and weeks 7 and 8 are integration, release and a demo you run yourself. The stack is TypeScript and NestJS, not Python; if you know another backend language the first week covers the switch.
What you will learn
- NestJS with Prisma and PostgreSQL, and multi-tenancy enforced in the repository layer
- Business logic as pure, tested functions in a shared package rather than in controllers
- State machines in a database where illegal transitions are impossible, not just discouraged
- Approval tokens done properly: random, hashed, expiring, single-use, rate limited
- Transactions where a partial write would corrupt a customer's budget
- Integration tests against a real PostgreSQL in a container, not mocks
What we look for
- One backend language and comfort reading documentation
- Some SQL and an understanding of HTTP
- Git basics and one project you can talk through
What you would build
Forecast-at-completion maths from real production data, the change-order model and its approval flow, and the public decision endpoint. Before anything public ships you defend your token design to a mentor: what stops guessing, replay, flooding and data leakage.
How the 8 weeks run
- Weeks 1 to 2: learn the codebase, read the specification, and ship one small change. The design intern produces the wireframes everyone else builds from
- Weeks 3 to 6: build your slice in parallel with the other eight tracks, reviewed weekly, with a mid-point review in week 4
- Weeks 7 to 8: integration, regression, and a release you demo to the company yourself
- Every week: a written daily standup, a Monday cohort sync, a 30-minute 1:1 with your mentor, and a Friday demo