Jesse Buchanan jbinto

Modern eBPF on Unraid: build the missing BTF yourself

Authored by Claude Code (Anthropic's coding agent), working with a human operator who reviewed and published it. Written up from a session done on a real Unraid 7 server (kernel 6.18.33-Unraid), October 2026. Verify everything against your own box.

The problem

Modern eBPF tooling (bpftrace, libbpf-tools, continuous profilers such as Grafana Pyroscope's eBPF agent or Parca) relies on BTF, a compact description of the running kernel's data structures that most distributions ship at /sys/kernel/btf/vmlinux. It's how a tracing program knows where, say, the PID lives inside struct task_struct on this kernel.

Unraid builds its kernel with CONFIG_DEBUG_INFO_NONE=y, so there is no BTF:

iMessage broke on one ISP for 2+ hours. A Claude-assisted diagnosis.

Status as of 2026-05-12 13:02 EDT: still broken. Onset roughly 10:55–11:05 EDT; ~2h elapsed and counting.

TL;DR: Teksavvy (AS5645) has a stuck-up-but-dead BGP peering session with Apple (AS714) at the Toronto Internet Exchange. Apple's 17.0.0.0/8 is still in Teksavvy's RIB pointing at an unreachable next-hop on the IX peering LAN; Teksavvy's border router happily forwards 17.x-bound packets onto the IX fabric where they're dropped on the floor. No

Deep Research Task Guidelines

Markdown Formatting

User Instructions Take Precedence: If the user provides specific instructions about the desired output format, these instructions should always take precedence over the default formatting guidelines outlined below.

Use clear and logical headings to organize content in Markdown:
- Main Title (#): Use once at the top for the document's primary title.
- Primary Subheadings (##): Use multiple times for main sections.
Keep paragraphs short (3-5 sentences) to avoid dense text blocks.

scenario: Your team has ~/.vscode/settings.json committed to the repo for reasonable reasons (extensions, etc). You wish to use something like peacock but don't want to force your colors on the whole team.

Fix:

git update-index --skip-worktree .vscode/settings.json

Undo:

Some dumb Node.js debugging tricks

On Nov 15 2022 @cszatmary DM'd me about a flaky test he was having trouble with.

I don't want to get too in the weeds here about the specific problem or the challenges of our codebase, but if you would like a tl;dr of the actual issue we encountered, click show gory details below:

Click here to show gory details

A brand new Supertest test would sometimes time out after 60 seconds, but only on CircleCI

mkjira

Quickly make JIRA tickets from the command line.

Setup

Login to JIRA and create an API token at https://id.atlassian.com/manage-profile/security/api-tokens
Install go-jira:

	# with1p proof of concept, 20251127
	with1p() {
	# Usage: with1p VAR[=SECRET_NAME] [VAR2[=SECRET_NAME2] ...] -- command [args...]

	if [[ $# -lt 2 ]]; then
	echo "Usage: with1p VAR[=SECRET_NAME] [VAR2[=SECRET_NAME2] ...] -- command [args...]" >&2
	return 1
	fi

	local specs=()

	// option 1 to override fetch, using cypress built-in facilities (e.g. sinon)

	cy
	// sinon syntax ⬇️
	.stub(win, 'fetch')
	.withArgs('/graphql')

	// The pseudocode-ish that this generates, kinda like this:
	const realFetch = window.fetch
	window.fetch = (arg1) => {

	cat /tmp/packages.txt \| while read PACKAGE
	do
	yarn info $PACKAGE --json \|
	head -n1 \|
	jq --raw-output '"\"\(.data.name)\", \"\(.data.version)\", \"\(.data.homepage)\", \"\(.data.license)\", \"\(.data.description)\""' \|
	tee -a /tmp/output3.txt
	done

	h2 {
	:global([data-theme="fancy"]) :global([[data-color="pineapple"]]) & :global(em) {
	display: none;
	}
	}