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· Lars Nielsen

A Setup Step That Rewrote /etc/passwd and Took polkit, Wi-Fi and Logins With It

My from-scratch Linux build boots into a KDE Plasma desktop now, and for a while it booted into one with a strange set of problems. Wi-Fi scans in NetworkManager didn't work. Power management didn't work. Login sessions weren't being registered properly. Three subsystems with nothing obvious in common, all broken at once.

Read article A Setup Step That Rewrote /etc/passwd and Took polkit, Wi-Fi and Logins With It
· Lars Nielsen

Two Graph Databases, Evaluated Independently, Both Abandoned Before Real Use

Two different graph databases got evaluated for the same search engine, three weeks apart, by way of two completely independent efforts. Neither one made it into production. The second attempt's own closing writeup ends up explaining, cleanly, why the first one never had a chance either — even though nobody set out to prove that when either evaluation started.

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· Lars Nielsen

Why the Graph Database's Own Query Language Had to Be Skipped for the Bulk Load

Loading data into a graph database usually means writing it in the graph database's own query language. For one real workload — 388 million edges — that turned out to be the one approach guaranteed not to finish. The fix wasn't a tuning flag or a bigger machine. It was skipping the query language entirely.

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· Lars Nielsen

A Build Step That Needs the Internet, Inside a Chroot That Doesn't Have It

A build running inside a chroot on this project has no network access, by design — every source tarball is fetched ahead of time and extracted locally, and nothing in the build process is supposed to reach outside the machine while a package compiles. One package's default configuration quietly assumes otherwise.

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· Lars Nielsen

One Data File Added Because a Build Script's Fallback Path Doesn't Exist

One package in this from-scratch build's KDE stack contains no compiled code at all. It's a database of hardware IDs — PCI, USB, and PNP vendor and device names — and it exists only because a different package's build script checks for a specific file at configure time, before anything about hardware detection actually matters at runtime.

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· Lars Nielsen

A Vulkan Helper That Can't Exist Because Qt6 Was Never Built With It

Most of the compatibility work in this build's KDE packages involves code that compiles fine but never actually runs — dead paths behind a runtime check that always evaluates false. This one is different: two small helper programs that don't compile at all, because the graphics toolkit underneath them was never built with the one feature they need.

Read article A Vulkan Helper That Can't Exist Because Qt6 Was Never Built With It
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