Backend Development
APIs and services (REST, gRPC, GraphQL) built for correctness, performance and maintainability.
Backend engineering · Netherlands · Remote-friendly
Backend systems that scale, ship, and stay up.
Sinmux builds reliable APIs, data platforms and cloud infrastructure for teams that need senior backend engineering. Available on contract, per project, or freelance.
Available for new work
// Services
What I do
Senior backend engineering, end to end.
Cloud & DevOps
Infrastructure-as-code, CI/CD pipelines, containers and observability on AWS and GCP. Ship safely and often.
System Architecture
Designing scalable, fault-tolerant systems. Monolith-to-microservices, event-driven design, and technical strategy.
Full-stack & Integrations
End-to-end features, third-party API integrations and data pipelines that connect your systems together.
// Work
Selected work
A sample of systems I’ve designed and built.
Live · 1000s of listings
Autocijfers.nl
Role: Founder, backend & data
An independent data product for the Dutch car market. It aggregates thousands of listings from Dutch marketplaces into clear per-model figures: asking price, monthly running costs, depreciation and reliability.
View project → // Stack
Stack
Tools I reach for to get backend systems into production.
Languages
- Go
- Python
- TypeScript
- Java
- Kotlin
Backend
- Node.js
- FastAPI
- Spring Boot
- gRPC
- GraphQL
- REST
Data
- PostgreSQL
- Redis
- Kafka
- Elasticsearch
- MongoDB
Cloud / DevOps
- AWS
- GCP
- Docker
- Kubernetes
- Terraform
- CI/CD
// About
About Sinmux
Sinmux is the backend engineering practice of a senior software engineer based in the Netherlands. The focus is simple: design and build server-side systems that are correct, observable and fast, and that keep working under real-world load.
After years building and operating production backends, I now take on contract, project and freelance work for teams that need an experienced pair of hands on the hard parts: API design, data modelling, performance, and cloud infrastructure.
Pragmatic, communicative and outcome-driven. I plug into your team or run a piece of work independently, whatever fits.
10+ yrs
Backend experience
NL
Based, remote-friendly
EN / NL
Working languages
// Contact
Let’s build something
Have a backend project, a contract role, or an architecture problem to solve? Tell me about it.