Full-stack developer · available for select work
I'm Sebastjan. I design and engineer secure, high-performance systems — from government messaging and enterprise identity platforms to EV networks and AI automation. Software engineering teams trust in production.
Environments I've built for
Selected work
A cross-section of what I've shipped — from public-sector infrastructure through to the products I'm building now.
Government messaging gateway
A resilient government messaging gateway routing secure citizen notifications at scale — engineered for strict auditability, hardened security and zero-downtime reliability. Running in production for 6 years with minimal maintenance.
Identity & access, Norwegian market
Identity lifecycle and single sign-on for Norwegian customers — building Novell IDM drivers, user provisioning and access policies with Access Manager.
Fleet & driver management
An enterprise management app for EV charging fleets, driver sessions and automated billing — delivered full-stack with robust Keycloak identity infrastructure.
Charging simulation engine
A simulation engine for EV charging networks, built ground-up to model stations, load and protocols.
AI automation for companies
A platform that helps companies design and run AI-driven workflows. My current product focus.
End-to-end launch — web, hosting, email, domain
Took a startup's board game from idea to online in one engagement: brand-forward marketing site, domain and DNS, managed hosting, and professional email — fully set up and running. A fast, mobile-first, SEO-ready Astro build.
Drag-and-drop ad production at scale
A visual, drag-and-drop builder for producing interactive digital ad creatives — design once, then generate and adapt thousands of on-brand variations across formats and channels. Built for a leading ad-tech platform used by global brands.
Paint-matching mobile game
Match paint, build combos and unleash boosts to reach the flag before time runs out. An original mobile game from s4Labs, coming soon to Android and iOS. Explore the game and watch real gameplay.
“We came to Sebastjan with a name and not much else. He sorted out the whole thing — site, domain, hosting, email — and had us online without any fuss. It's quick, it works properly on a phone, and honestly I haven't had to think about it since.”
“Six years on, the gateway he built is still pushing out citizen notifications every day without a hiccup. It just runs. Sebastjan was on our team back then, and even after he went out on his own we kept his number. When something actually matters, he's who we call.”
How I help
End-to-end web application engineering, from an empty repository to a scaled production environment. I take full ownership of architecture, delivery and system quality.
Identity, access and messaging infrastructure where zero-downtime reliability and absolute auditability are non-negotiable.
Inherited a fragile, slow or tangled codebase? I audit, stabilize, optimize and refactor it into a maintainable asset.
About
I've spent my career on systems where getting it wrong is expensive — government messaging, identity and access, EV infrastructure. I bring that same discipline to every build, in Vue, Angular, React, .NET and Rust.
s4Labs is where I work in the open: shipping products like Hive, helping launch Fastbreak, and partnering with a small number of teams each year.
Tell me what you're building. I reply to every serious enquiry within a day — and if I'm not the right fit, I'll tell you honestly.