Treevoxa offers NestJS development services for teams building back ends that will grow: many modules, many developers, and an API that web and mobile apps depend on. We write TypeScript on NestJS with Prisma and PostgreSQL, and two of our own products run on it: MatrixHR and Callboard.
A NestJS development company with NestJS in production
MatrixHR's API is a NestJS application in a monorepo with a shared types package and a database package. In it:
- Modules for employees, attendance, leave, payroll, expenses, loans, recruitment and more, each with the same structure.
- Guards with Passport and JWT for authentication, and role checks on every route.
- Validation pipes with class-validator and class-transformer on every request.
- Throttling and security headers on every endpoint.
- OpenAPI documentation generated from the code with the Swagger module.
- Prisma on PostgreSQL for typed queries and migrations.
- Files and documents: PDF payslips, Excel imports, document parsing and storage on Amazon S3.
Callboard, our AI phone agent product, runs on NestJS with Prisma and PostgreSQL-backed sessions.
NestJS API development we offer
- New back ends and REST APIs for SaaS products, business systems and mobile apps.
- Monorepos where the API, the web app and the mobile app share types.
- Migrations from Express to NestJS, module by module, without a big-bang rewrite.
- Audits and rescues for NestJS projects that have grown hard to change.
Tech stack for NestJS projects
| Part | What we use |
|---|---|
| Framework | NestJS, Express platform |
| Language | TypeScript |
| Data | Prisma, PostgreSQL |
| Auth | Passport, JWT, role guards |
| Validation and docs | class-validator, class-transformer, Swagger (OpenAPI) |
| Services | Amazon S3, email, PDF and Excel generation |
Technologies related to NestJS
NestJS is our framework of choice for larger Node.js back ends; see Node.js development services for Express and the wider picture, and Next.js development services for the front ends we pair it with. For API design in general, see API development services.
How a NestJS project runs
- Domain map: the modules, the data each one owns, and how they talk to each other.
- Written scope and quote.
- Build in short cycles with tests and type checks on every change.
- Deploy in containers, with migrations, logging and monitoring.
- Support under a written agreement.
Engagement models for NestJS work
- Fixed scope for a defined back end or API.
- Dedicated NestJS developer working only on your product, billed monthly. See hire dedicated developers.
- Hourly for audits, fixes and small changes.
What NestJS development costs
The cost of a NestJS back end depends on the number of modules, integrations, data migration and testing. Our custom software development cost guide explains how quotes are built, and software developer hourly rates compares what teams charge. We quote in US dollars, in writing.
Who NestJS development is for
- SaaS products with many modules and a growing team.
- Companies replacing an aging back end with a typed, structured one.
- Teams with Angular-style structure in mind who want the same discipline on the server.
- Monorepos where the API, the web app and the mobile app should share types.
NestJS pitfalls we avoid
- Fat controllers. Business logic lives in services, not in route handlers, so it can be tested and reused.
- Circular module dependencies, a common source of startup errors and confusing code. Module boundaries follow the domain.
- Validation in some places only. A global validation pipe rejects bad input on every route.
- Permissions in the front end. Guards check roles on the server for every request.
- Docs that drift. OpenAPI documentation is generated from the code, so it cannot fall behind.
What to send us for a NestJS quote
What the back end must do, the clients that will use it, expected traffic, and any existing code or API documentation.
How do you test NestJS code?
Unit tests for services, integration tests for modules against a real database, and end-to-end tests for the main API flows, all run automatically on every change.
Upgrading NestJS
NestJS releases new major versions regularly. We keep projects on supported versions, upgrade dependencies in small, tested steps, and read the migration notes before each major release, so an upgrade is a routine task rather than a project.
Questions to ask before you hire a NestJS team
- Can we see a NestJS back end you run in production?
- How do you structure modules as the system grows?
- Where are permissions enforced?
- How is the API documented, and does the documentation stay current?
- What do your tests cover?
Ask every bidder the same questions, in writing, and compare the answers before you compare the prices.
Working across time zones on NestJS projects
We work remotely with a daily overlap window in your working hours, agreed before the project starts.