Web, API and backend development
Production websites, web apps, and APIs that have to keep working long after launch. I write the front end with care for Lighthouse and accessibility, and the back end with care for cost, observability, and the next person who has to read the code.
Based in Groningen, working across the Netherlands and remotely for clients worldwide.
Production websites, web apps, and APIs in React, Preact, Svelte, and vanilla web. Backends in Go and Python with REST or event-driven APIs.
Either green-field or careful, well-tested changes to an existing codebase. I care about Lighthouse scores and total cost of ownership, not just shipping.
Good for
- Marketing sites and product sites where Core Web Vitals matter.
- Internal and public APIs (REST, SSE, websockets) that need to be reliable, not just functional.
- Replacing a slow or fragile codebase without a full rewrite.
How I approach it
- Fit the architecture to the problem. A marketing site, a dashboard, and an API have different needs. A content site gets Astro and barely any JavaScript, a dashboard gets React or Svelte, an API gets Go.
- Speed. Fast pages and fast APIs come from decisions made early, so I profile and measure instead of guessing. This site itself is built the same way I build for clients.
- APIs designed for their consumers. Whether REST or event-driven, an API is a product for the developers who use it. Clear contracts, versioning, and error behavior come first.
- Operations included. CI/CD, deployment on Cloudflare or your own infrastructure, and monitoring are part of delivery. You get a system you can run yourself, documentation included.
Work I can show
- Logic Nodes. A browser-based circuit editor rendered on a hand-written HTML5 canvas, in TypeScript with a little Svelte. See the project.
- go-catdoc. An open-source Go library for extracting text from legacy Word documents. View on GitHub.
- kriyak.com. This site: server-rendered Astro on Cloudflare with structured data, bilingual routing, and no client-side tracking. The source is public. Browse the source.
Tech I work with
TypeScript, React, Preact, Svelte, Astro, Tailwind, Go, Python, FastAPI, Postgres, Redis, Cloudflare Workers.
Frequently asked questions
Do you handle hosting and deployment too?
Yes. I can ship to most major hosting platforms and set up CI/CD so future deploys are pushbutton. Cloudflare is a frequent default, but it's not a requirement.
Can you work on our existing API or do we need to start fresh?
Either. Adding endpoints, refactoring, or replacing a slow service all fit, as long as we agree on the scope of the change up front.
Do you build accessible (WCAG) websites?
Yes. WCAG 2.2 AA is the default target. I test with keyboard and screen-reader basics on every project, and document where the build still falls short so it's not a surprise.
Can you take over an existing codebase?
Yes, that is common. I start with a short audit to map the state of the code, the deployment, and the risks, and then propose improvements in slices instead of a rewrite.
Do you offer maintenance after launch?
Yes. Most clients move to ad-hoc hourly work or ongoing support after delivery. There is no lock-in: you own the code and can stop or switch at any time.
Want to talk it through?
Tell me what you're trying to do. I'll let you know honestly whether I'm a good fit.
Get in touchOther services
- Custom application development End-to-end design and implementation of bespoke applications across web, native iOS, and backend systems, including MVP builds for early-stage products.
- AI and LLM integration LLM-powered features for existing apps and new products: agent workflows, RAG pipelines, and integrations with OpenAI, Anthropic, and similar providers.
- Legacy code modernization Refactoring and modernizing older codebases. Framework upgrades, careful test-driven changes, and migrations from end-of-life platforms.
- Native iOS apps Native iPhone and iPad apps in Swift and SwiftUI, including widgets, Live Activities, and App Store delivery.
- Browser extensions and integrations Chrome extensions, Thunderbird add-ons, and integrations between browsers and external services.
- Point-of-sale and retail software Custom POS systems, inventory and stock management tooling, and integrations with receipt printers and other store hardware.
- Performance-critical engineering Algorithms, audio and video processing, codec work, P2P networking, and other engineering-depth projects where performance and correctness matter.