Software Engineer · Portfolio

pronounced/ˈkat͡s.pɛr/

Software Developer @ Stofloos, based in Eindhoven, The Netherlands.

I build apps and tools, tinker with hardware, and occasionally write about the rabbit holes I fall into.

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Kacper
Now
Coded this week
  • Unknown42%
  • Typescript25%
  • TSX14%
  • Markdown5%
  • Python4%
  • Other9%
Latest on GitHubemilkowalski/skills · 4 recent
Room24.9°C
Featured projectsView all →
payload-reactive-collectionsMake Payload CMS collections reactive over WebSockets in Next.js — the library behind this site.2026
KakasPersonal cash-flow forecasting: the "money situation" spreadsheet rebuilt as a web app.2026
React Native for the reMarkable Paper ProWrite React apps in JSX and run them natively on a reMarkable Paper Pro e-ink tablet.2026
Latest post
Downgrade MacOS without second mac (M1)

When the macOS 12 beta left my M1 Mac soft-locked in recovery with no way to pick an older installer, I rebuilt a Big Sur installer by swapping the SharedSupport payload — no second Mac needed. Step-by-step, with the exact commands.

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