Vilhelm Martinsson

Full-Stack Engineer · Sweden

I build web applications from idea to production, working across frontend, backend, real-time systems, and practical AI features.

Services

Product development

Web applications built from idea to production, across frontend, backend, APIs, and infrastructure.

  • Frontend interfaces and authenticated applications
  • Backend systems, APIs, and database design
  • Payments, integrations, and third-party services
  • Deployment, hosting, and production environments

Real-time systems

Interactive applications with live updates, background processing, and asynchronous workflows.

  • WebSockets and live browser updates
  • Background jobs and scheduled tasks
  • Long-running processes and progress flows
  • Event-driven application behavior

AI integrations

Practical AI features integrated into real products and existing workflows.

  • LLM integrations and API-based workflows
  • AI-assisted automation and content handling
  • Streaming responses and interactive AI features
  • Production-aware implementation and cost handling

How I work

Most of my work takes one of two forms: a bounded project or an ongoing contract. Either works for me. What matters is that we align early on what "done" means and how we stay in sync when the scope or priorities change.

Project work

The goal is bounded (an MVP, an internal tool, a slice of product). I scope it, build it, ship it, and hand you something you can actually run.

Ongoing contract

You want engineering that doesn't end at launch: roadmaps change, bugs show up, new work stacks up. That fits when you're not looking to hire yet but still need someone technical in the loop.

In both cases I own the technical decisions and the implementation. I'll use AI in the workflow when it saves real time; product features get AI only when there's a concrete reason for users.

Technologies

Backend

Python, Django, Django REST, PostgreSQL

Frontend

JavaScript, Vue.js, Nuxt.js

Real-time & Infrastructure

Django Channels, WebSockets, Celery, Linux, Nginx

Integrations & APIs

Stripe, Mailgun, OpenAI, Claude

Selected Work

Blog

A place to scribble down my thoughts and ideas, while diving deeper into subjects that spark my curiosity. It will be a mix of personal and professional notes on a wide range of topics.

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Testimonials

"Vilhelm has been helping us develop a custom content management system using Django, Django REST, Celery, and third-party APIs. It allows us to manage multiple sites, schedule articles, and generate images with ease. The ongoing, iterative approach has been smooth, and we're very pleased with the result."

Anders Gärme — Webbstream

"Vilhelm developed our MVP for a live, local quiz competition, covering both front and back end, and enabling players to compete for cash prizes with Swish payments. The development process has been efficient, and the final product meets our needs perfectly."

Andreas Asplund — Grannkampen

"Vilhelm has helped us with everything from requirements, design, development and implementation of our web application. The collaboration has been very good from start to finish and the project was delivered according to plan!"

Linus Lindeborg — Hälsoförmedlingen