The ports tree, ZFS, jails, pf, and the internals of a Unix built for correctness.
A deeper look at FreeBSD's Capsicum framework — cap_rights, the process descriptor model, and how to structure a service around capability mode instead of bolting it on afterward.
The most common reasons a bhyve guest hangs or fails at boot when using UEFI firmware instead of the legacy BIOS loader, and how to tell which one you're actually hitting.
FreeBSD won't boot and the loader can't find the boot partition. Here's how to inspect and repair the GPT partition table from a live/rescue environment.
How to tell whether a flapping network interface is a cabling/physical-layer problem, a switch-side issue, or a driver/firmware problem, using FreeBSD's own interface statistics.
FreeBSD panicked and rebooted. Here's how to get the crash dump kgdb actually needs, and how to read it well enough to find the responsible driver or subsystem.
Why ntpd sometimes refuses to correct large clock offsets, how to read its own diagnostic output correctly, and when stepping the clock manually is the right call instead of waiting.
New connections start silently failing on a busy firewall, and pfctl reports the state table is full. Here's how to confirm it and size the table correctly for real traffic levels.
How to find which rc.d script is actually holding up boot, distinguish a genuinely slow service from an unnecessary dependency chain, and fix each case differently.
ZFS looks like it's eating every gigabyte of memory on the system. This is the Adaptive Replacement Cache working as designed — here's how to confirm that and tune it if it's genuinely a problem.
What a Solaris-assert-style ZFS panic actually means, why it almost always points to genuine pool corruption rather than a kernel bug, and how to safely get the system back up.