Quality assurance for district heating - AGFW research project
QSmart
April 2026 - present
Overview
A site diary is a legal record, and on a district heating job it is still kept on paper: who turned up, the weather, the work done, what went wrong, photos to prove it - written in a van and typed up later, if it survives the week. This is that diary on a phone, filed against the right job the moment it is written, so nothing is lost between the builder, the client and the inspector. Built at Smartdings GmbH for AGFW, the German district heating association, on a government-funded research project. I work on both sides of it - the React Native app and the NestJS API behind it.
Stack
Mobile
- React Native
- Expo Router
- TypeScript
- NativeWind
App data
- TanStack Query
- Zustand
- React Hook Form
- Zod
- i18next
API
- NestJS 11
- Fastify
- Drizzle ORM
- PostgreSQL 17
- Zod
Platform
- AWS S3
- Docker
- Better Auth
- Azure Pipelines
- EAS
What I built
- 01Built the site diary and the document library end to end - the React Native app screens and the NestJS server behind them.
- 02Set up the backend service and led its development under a mentor, reviewing the team’s code along the way.
- 03Set up the photo and file storage on AWS S3. The phone uploads straight to the bucket using a signed link, so the server never has to hold a large file.
- 04Works with no signal. TanStack Query saves entries on the phone and sends them up once it finds a network.
- 05A finished diary turns itself into a PDF report, photos included, right on the phone.