cel-kdev

Claude Code and Codex skills for Linux kernel development workflows.

Skills

stg

Teaches coding agents to use StGit for patch management instead of raw git commands. When StGit is active on a branch, the agent creates, edits, reorders, and squashes patches through stg rather than git commit and git rebase, avoiding stack corruption. Covers conflict resolution, series navigation, and the prohibition on parallel stg operations across subagents.

perf

Guides coding agents through analyzing perf record captures: recording options, symbol resolution with kallsyms, call-graph analysis, flamegraph generation, and a structured reporting workflow (overview, drill-down, comparison).

drgn

Teaches coding agents to inspect a running kernel through /proc/kcore using drgn. Covers core API patterns (Object creation, pointer handling, type introspection), per-CPU variable access, stack traces, container_of usage, and slab cache inspection. Includes subsystem-specific recipes for SUNRPC, NFS, and AIO, along with workarounds for common pitfalls.

trace-cmd

Guides coding agents through analyzing kernel trace captures (.dat files) from trace-cmd. Covers event ingestion, latency distributions, throughput measurement, phase detection, and filter expressions. Includes a subsystem reference for NFS/RDMA server and client events (sunrpc, svcrdma, xprtrdma, nfsd), RPCGSS, workqueue, scheduler, TCP, and TLS handshake tracepoints.

b4

Teaches coding agents the b4 patch workflow for applying patches from lore (b4 am), comparing series revisions (b4 diff), and managing outbound patch series with b4 prep and b4 send. Covers coexistence with StGit, cover letter strategies, recipient management, and non-interactive operation constraints.

sashiko

Teaches coding agents how to retrieve and interpret reviews from the sashiko kernel-patch review bot. Points at the unauthenticated /api/patchset endpoint and away from two common dead ends: lore searches (the bot does not post to public lists by default) and fetches against the SPA web UI (returns only the app shell). Covers the email delivery policy, review-status transitions, and the false-positive rate that governs how review output should be treated.

Layout

.claude-plugin/
  marketplace.json   # marketplace manifest
  plugin.json        # top-level plugin metadata
.agents/plugins/
  marketplace.json   # native Codex repo marketplace
plugin/cel-kdev/
  .claude-plugin/
    plugin.json      # plugin manifest
  .codex-plugin/
    plugin.json      # Codex plugin manifest
  hooks/
    block-raw-git.sh # StGit raw-git guard
    hooks.json       # Codex lifecycle hook wiring
  skills/
    b4/SKILL.md
    drgn/SKILL.md
    stg/SKILL.md
    perf/SKILL.md
    sashiko/SKILL.md
    trace-cmd/SKILL.md

Requirements

The block-raw-git.sh PreToolUse hook (installed by the Claude Code manifest and by Codex plugin hooks) parses the harness's tool-input JSON with jq, so jq must be present on the host:

apt install jq      # Debian, Ubuntu
dnf install jq      # Fedora, RHEL

The hook aborts with a diagnostic when jq is missing rather than failing open.

Install for Claude Code

claude plugin marketplace add chucklever/cel-kdev
claude plugin install cel-kdev

Install for Codex

Codex can consume the native marketplace at .agents/plugins/marketplace.json, the legacy-compatible marketplace at .claude-plugin/marketplace.json, or the individual SKILL.md directories.

For normal installs from GitHub, add the marketplace:

codex plugin marketplace add chucklever/cel-kdev

Then complete the install from /plugins inside Codex. When developing this repository locally, Codex also discovers the repo marketplace at .agents/plugins/marketplace.json.

If the marketplace path is unavailable, the skill installer script fetches the SKILL.md directories directly as a fallback:

python3 ~/.codex/skills/.system/skill-installer/scripts/install-skill-from-github.py \
  --repo chucklever/cel-kdev \
  --path plugin/cel-kdev/skills/b4 \
  --path plugin/cel-kdev/skills/drgn \
  --path plugin/cel-kdev/skills/perf \
  --path plugin/cel-kdev/skills/sashiko \
  --path plugin/cel-kdev/skills/stg \
  --path plugin/cel-kdev/skills/trace-cmd

Restart Codex after installation.

Codex hook setup

The Claude Code plugin manifest installs a PreToolUse hook that blocks raw git commands on branches with an active stg stack. Codex loads the same hook from plugin/cel-kdev/hooks/hooks.json when the plugin is enabled.

Codex hooks are enabled by default. To disable them, set:

[features]
hooks = false

After installing or updating the plugin, open /hooks in Codex and trust the cel-kdev hook definition. If you install only the individual skills instead of the plugin, wire the hook manually in ~/.codex/hooks.json (user-level) or <repo>/.codex/hooks.json (per-repo):

{
  "hooks": {
    "PreToolUse": [
      {
        "matcher": "^Bash$",
        "hooks": [
          {
            "type": "command",
            "command": "/home/YOU/src/cel-kdev/plugin/cel-kdev/hooks/block-raw-git.sh",
            "timeout": 5,
            "statusMessage": "Checking StGit policy"
          }
        ]
      }
    ]
  }
}

The script exits 2 with the reason on stderr when it blocks, matching Codex's documented deny protocol. Codex notes that shell interception is incomplete for newer streaming-shell execution paths, so treat this hook as defense in depth rather than a hard guarantee.

Releasing

Claude Code and Codex cache installed plugin contents, so every push that changes plugin contents needs a fresh version. Bump it with:

scripts/bump-version.sh 2.4.2

All three manifests are rewritten in place. Commit the bump as its own patch, separate from the content change it accompanies:

git add plugin/cel-kdev/.claude-plugin/plugin.json .claude-plugin/plugin.json plugin/cel-kdev/.codex-plugin/plugin.json
git commit -m "cel-kdev: Bump plugin version to 2.4.2"

Or with StGit:

stg new bump-2.4.2 -m "cel-kdev: Bump plugin version to 2.4.2"
stg refresh

A pre-push hook under scripts/git-hooks/ enforces the bump on every push that touches .agents/plugins/, .claude-plugin/, or plugin/, and also fails when the manifests disagree. Activate it once after cloning:

git config core.hooksPath scripts/git-hooks

License

MIT