Engineering blog

Notes from building an OS from scratch.

Milestones, deep dives and honest write-ups: what works, what broke, and what we learned. Written by the engineers, straight from the source tree.

31 August 2026

Chromium goes multi-process on EuroOS.

The July wall is down: real GL through SwiftShader, a renderer in its own process, frames crossing address spaces over shared memory, and a browser on the desktop that paints and stays up. Plus the NMI forensics we built when the machine froze solid, and what honestly remains.

31 August 2026

No more minimum viable: the EuroOS apps grow up.

Our founder said it plainly: everything you build is MVP quality. He was right. A real painting app, an image viewer with a from-scratch JPEG decoder, rich text, per-file versioning and protection in the filesystem, and a system-wide search. Finished features, verified by running them.

27 August 2026

Chromium browses the web on EuroOS.

A real, unmodified Chromium fetched and rendered euro-os.eu from the live internet: our own DNS, our own TCP stack, our own drivers, and Blink painting the result. Plus clicking, typing and navigation through a kernel-side DevTools bridge, and what honestly remains.

8 September 2026

EuroOS now updates itself.

A signed channel on euro-os.eu, the new kernel over EuroTLS, an A/B slot partition, a loader that verifies before it boots, automatic rollback. Proven end to end today from a QEMU install against the live server, with the three bugs that only appeared once the whole chain ran for real.

8 September 2026

What it costs to build an OS without venture capital.

Three months, 520 commits, 120,000 lines of Rust, 987 tests, 0 patrons. The real numbers behind EuroOS, why physical test hardware matters more than rented servers for GPU and networking support, and why our first funding goal is a deliberately small 500 euro a month.

22 July 2026

The critics were right.

A sharp bug report on hup.hu took our idle desktop from 98% CPU to 6%, surfaced a real APIC hazard that only bites under KVM, and asked a fair question about Rust. What was real, what the actual mechanism turned out to be, what we fixed, and how to verify it yourself.

20 July 2026

Running real Chromium on a kernel we wrote ourselves.

The actual Chromium binary, demand-paged from disk, running its entire startup on a from-scratch kernel. The bugs it found, why single-process headless is a dead end, and how we taught the kernel to fork a half-gigabyte process. A deep dive on a bring-up in progress.

14 July 2026

EuroOS on real hardware: the "Metal" phase.

From running in a VM to booting and installing on a modern laptop: from-scratch NVMe, AHCI, USB and Intel-NIC drivers, root-on-NVMe, TPM over the firmware interface, and driverless printing and scanning. A small class-standard driver base, not a legacy one, verified against a hardware matrix.

13 July 2026

DOOM runs on EuroOS. Here is why that matters.

The real 1993 engine, unmodified, as a userspace program on our from-scratch kernel. What the port forced us to build, the four bugs it found, and how its test harness root-caused a boot race that had been hiding in the interrupt layer.