What I do
I work across the full stack: back end systems, front end interfaces, APIs, databases, and the infrastructure that ties them together. Core languages include C++, Python, PHP, and JavaScript. After 15 years in the field I am comfortable picking up whatever your project is built on.
New products
Design and build software from scratch, from the first architecture sketch to a system running in production.
Existing codebases
Extend, modernise, and clean up systems already in use, including performance work and hard-to-find bugs.
Team reinforcement
Step in as a senior engineer when your team needs extra capacity, expertise, or a safe pair of hands.
Deep expertise, modern speed
Fifteen years of hands-on programming, multiplied by modern AI tooling. I know exactly what good code looks like, so I can use these tools to their full potential and deliver working solutions in days rather than weeks.
How I work
Long-term engagements
Open-ended roles where I join your team as an ongoing contractor, part time or full time. Good for teams that need lasting senior capacity without a permanent hire.
Fixed-scope projects
Clearly defined projects with an agreed scope, timeline, and budget, delivered end to end. You know the cost and the outcome before work starts.
About me
My name is Daniel Jansson, and DJson Consulting is my freelance software consulting business. I hold a PhD in engineering physics, but programming and software development have always been my passion, and building software is what I have done professionally for the past 15 years. The research background comes in handy when a problem needs careful thought: numerical work, data-heavy systems, or anything where correctness matters.