About

Matthias Desard.

Building software professionally since 2015 — 11 years of it — and running Sater bv as the company behind that work.

I work best on systems that have to keep running: multi-tenant platforms, integrations that cannot lose a message, infrastructure someone else will inherit. Most of that has been Java and Spring on AWS, which is a deliberately unfashionable answer to what pays the bills and stays up.

The other half of my time goes to things I want to exist: open-source work like Let’s Peppol, which is being built because e-invoicing is about to be mandatory for every Belgian company and the access points in between charge for what should be free — and a self-hosted AI stack I run on my own hardware rather than rent by the token. Both feed straight back into the client work.

I work from Wolfsdonk, in Flemish Brabant, with clients in Belgium and Germany. Remote by default, on site when it genuinely helps.

What I work with

The list is honest rather than exhaustive: these are the tools I have shipped and operated production systems with.

Languages

  • Java 25
  • TypeScript
  • Python
  • SQL
  • Dart

Backend

  • Spring Boot 4.1
  • Spring Cloud
  • Spring Modulith
  • Hibernate
  • jOOQ
  • FastAPI

Data

  • PostgreSQL
  • PostGIS
  • Redis
  • ChromaDB

Cloud and delivery

  • AWS
  • ECS Fargate
  • Lambda
  • S3 / CloudFront
  • CloudFormation
  • Terraform
  • Docker
  • GitHub Actions

Front end

  • Astro
  • Flutter
  • Vue
  • HTML / CSS

AI

  • vLLM
  • llama.cpp
  • Ollama
  • MCP
  • RAG / vector search
  • Agent tooling

Clients

Named with permission. Long-running engagements, invoiced monthly.

  • Hippovibe

    Application architect and developer · 2016 — now

    Equestrian management SaaS — eight Spring Boot services, a web app and a mobile client, in production since 2016.

  • Glaswas Verelst

    Design, build and hosting · 2026

    A Webflow site rebuilt as a static Astro build on S3 and CloudFront — faster, indexable, and no monthly platform fee.

  • B4IT

    Software developer · 2024 — now

    A long-running development engagement, invoiced monthly since 2024.

Want the short version by e-mail?

Send me the shape of the problem and I will tell you whether I am the right person for it.

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