Koen · Sint Maarten

Small, honest software. Built on an island, made for anywhere.

I'm Koen. I make apps that work everywhere, cost nothing to keep, and keep your data yours. This is where they live.

Every Koen app is built from one colour in eleven shades. These are this site's.

See the apps Get in touch

Apps

Four so far. Each one started as something I needed, then got polished until someone else could use it.

  • PlumSafe

    Android · in development

    A savings dashboard that pays you first. Import bank statements, add cash spending, and see where the month actually went.

  • Tropical Mango

    Android · closed testing on Google Play

    A shopping list that sorts itself. Type an item and it lands in the right aisle, on your phone, offline.

  • Nudge

    Web app · in development

    Reminders that reach every device you're signed into, even with the app closed.

  • Tilt & Roll

    Browser games · live

    A series of tilt-controlled games that run in the browser. Nothing to install.

For businesses

I also build software for small businesses, usually the kind of tool that has been a spreadsheet for too long.

What I build

  • Inventory and stock-location systems for stores and warehouses
  • Order and job tracking that the whole team can see
  • Small internal web tools that replace a shared spreadsheet

Currently building: a self-hosted stock-location system for a store and its warehouse.

How it works

Self-hosted where possible. It runs on a machine you own, on your own network, so it keeps working when the internet doesn't.

No subscription to me. You own the code and the data, and you get a proper handover: install steps, a backup procedure, and a short user guide.

Talk about a project

How I build

I'm in Sint Maarten, in the Caribbean. Most software is built for the United States and works less well the further you get from it. Mine starts from the opposite assumption.

  • Works everywhere Currencies, date formats and services that are not locked to one region.
  • No subscriptions Free or one-time cost. Nothing that stops working when a card expires.
  • Your data stays yours On your device, or in accounts you already own, wherever that is possible.
  • One design language One colour in eleven shades, hairlines instead of shadows, the same rhythm in every app. Use one and you know the next.

Get in touch

For the apps, for testing, or for business work.

Email Koen