Custom application development
When the off-the-shelf option doesn't fit and a no-code tool would buckle under the requirements, I design and build the application from scratch. Web, iOS, backend, or all three.
Based in Groningen, working across the Netherlands and remotely for clients worldwide.
End-to-end design and implementation of bespoke applications across web, native iOS, and backend systems, including MVP builds for early-stage products.
I help with the full arc, from a vague brief to a working product. Suitable when you have a real problem to solve but the shape of the software is still open.
Good for
- Early-stage products that need a real MVP built from scratch.
- Internal tools that have outgrown spreadsheets or no-code platforms.
- Products with unusual constraints: offline, on-device or regulated. If there is hardware attached, embedded software is the closer fit.
How I approach it
- Start with the problem. Before any code, I want to understand what the software must achieve, who will use it, and what done looks like. You get a short written plan with scope, milestones, and a price per milestone.
- Working software early. The first usable version usually ships within a few weeks. Real feedback on a real build steers the rest of the project far better than a specification document can.
- Tech I can defend in five years. I pick technology I can still justify later: Postgres over whatever database is trending this month, tests where they earn their keep, and code another developer can pick up without a guided tour.
- After launch. Deployment, monitoring, and a clean handover are part of the job. Afterwards you can come back for improvements ad hoc, or not at all: you own the code either way.
Work I can show
- Readleap. A reading tracker for iPhone that I designed, built, and shipped to the App Store, including widgets and Live Activities. Read the case study.
- Logic Nodes. A free browser-based logic circuit simulator with a hand-written canvas editor, built in TypeScript. See the project.
Tech I work with
Go, Python, TypeScript, React, Preact, Astro, Swift, SwiftUI, Postgres, Cloudflare.
Frequently asked questions
What's the smallest project you'll take on?
Roughly one to two weeks of work as a single milestone. Anything smaller usually fits better as ad-hoc hourly work, which I also offer.
Will I own the source code?
Yes. The default contract assigns full IP and source code to you on payment. I keep the right to mention the project in a portfolio unless you prefer otherwise.
Can you build both the web and the iOS app for the same product?
Yes. Building web, backend, and iOS for the same product is a common shape of work. One person across the stack means fewer hand-offs and a more coherent end result.
How much does custom software development cost?
It depends on scope, so I quote per milestone after a free intake call. A small internal tool and a full customer-facing product are different orders of magnitude, and I would rather tell you honestly where your idea lands than quote a generic number. The intake and estimate cost nothing.
How long does it take to build an MVP?
Most MVPs land between several weeks and a few months of work. You see a first working slice much earlier, usually within the first few weeks, so you can correct course while it is still cheap to do.
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
- Web, API and backend development Production websites, web apps, and APIs in React, Preact, Svelte, and vanilla web. Backends in Go and Python with REST or event-driven APIs.
- AI prototype to production Turning a prototype built in Lovable, Bolt, Replit, v0 or Cursor into software you can safely put real users and real customer data on.
- 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.
- Embedded software and device integration Software that talks to physical devices, and firmware for the devices themselves. Driving equipment over serial, USB, Bluetooth LE, and MQTT, plus firmware for ESP32 and Arduino boards.
- Performance-critical engineering Algorithms, audio and video processing, codec work, P2P networking, and other engineering-depth projects where performance and correctness matter.