builds useful tools, fast
maarten brondijk · builder

I build useful tools. Fast.

Tools built with AI. Some are useful, some are just for fun.

Latest post I built a memecoin trading bot (and it's losing money) 2026-07-13 →
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Featured
Taste Lab demo with blind samples and a 0 to 10 rating scale Jimmy Joy Taste Lab

Jimmy Joy Taste Lab live

I got annoyed with the sliders in our tasting software. So I built Taste Lab for Jimmy Joy. Now we save €5,000 a year in software fees, run our own tastings, and keep improving the tool with the people who use it.

From tasting to report: Tap a score, add a comment and submit. Shelf-life tests have moved out of spreadsheets too, with a searchable history and the original tester comments. Built with AI using Next.js, Supabase and Vercel.
demo, no sign-in €5,000/year in software fees saved tastings + shelf-life tests
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Recent builds
WK 2026 Prediction Pool overview: header, full navigation, and a live match WK 2026 Prediction Pool

WK 2026 Prediction Pool live

An office World Cup pool I built instead of paying Scorito €200 per group: idea to live in about an hour, now used by 30 colleagues. Live scores, match minutes and goalscorers auto-import from a public API, and the leaderboard reshuffles in real time during matches. Weekly bonus rounds, closest-guess metagames, fully customizable scoring. Free, no ads.

How: React + Vite on Netlify Functions & Blobs, fully serverless, no database. Live match data pulled from a public football API.
30 players 104 matches live scores via API idea → live in 1h €200 saved
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Thousand Nights homepage with story, essay and poem categories Thousand Nights

Thousand Nights live

A reading machine for a 1,000 day list: one story, one essay and one poem per day, 3,000 texts in total. It picks your next unread text, tells you how long it takes, opens it in the app, and keeps your reading log in sync between devices.

How: Plain JavaScript on GitHub Pages, no framework and no backend while reading. A Python importer pulls public domain texts from Gutenberg; Supabase syncs the reading log.
3,000 selections 1,313 readable works offline
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Tools that run daily
Stock Dashboard JJ Stock Dashboard · JJ

Stock Dashboard · JJ daily

An operational stock command-centre for a nutrition brand that tracks every SKU across EU & US, flags below-safety and critical stock, and projects out-of-stock dates from the live subscription queue.

How: Python pipeline off Google Sheets masters → a fast static dashboard. Automatic safety-stock and reorder logic, EU/US toggle.
51 SKUs EU + US €453K stock value
internal tool · screenshots only
Master Insights dashboard Master Insights

Master Insights daily

A revenue command-centre: month-to-date vs target pacing, channel split (Shopify vs Recharge, INT vs US), subscription share, and a daily revenue-vs-target curve against last year.

How: Aggregates daily sales across channels into one EUR view (incl. USD conversion) with live pacing against monthly targets.
MTD pacing multi-channel EUR + USD
internal tool · screenshots only

Order Visualizer 2025

A 3D globe that draws every order shipped from Amsterdam to the world: glowing arcs from the warehouse to each destination city. See it in action in my LinkedIn post.

How: Mapbox GL globe with great-circle arcs generated from anonymised order geodata. Only city and postal code, no personal data.
Order Visualizer globe showing shipping routes from Amsterdam Watch on LinkedIn ↗

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More projects
Claude usage SwiftBar plugin dropdown Claude usage

Claude usage in your menu bar

A SwiftBar plugin that shows your Claude Code plan usage and rate limits in the macOS menu bar, so you see a limit coming before you hit it.

SwiftBarmacOSopen source
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Flightvisualizer global flight map Flightvisualizer

Flightvisualizer.com

Real-time flight tracking visualization with global coverage.

pythonmaps
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Taskflow project overview page Taskflow

Taskflow-done.com

Minimalist task management with automation built in.

webautomation
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Side quests project page featuring Squat Coach Side Quests

Fun Side Quests

A collection of smaller, experimental projects and coding adventures.

experiments
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From the blog
2026-07-04 · infra

Setting up a devbox with Hetzner

A short, practical guide to spinning up a cheap, always-on cloud development box on Hetzner in about ten minutes.

See all posts →