feat: bind your own shell commands to keys on each screen

[JacobAtchley]

What

The config gains a commands list. Each entry binds a single key, on a kind of screen (pullRequest, workItem or build), to a shell command of your own:

"commands": [
  { "on": "pullRequest", "key": "ctrl+r", "name": "review with claude", "run": "~/bin/pr-review.sh" }
]

On that screen, pressing the key runs the command detached, with what the screen shows passed in BOARDWALK_* environment variables (ID, TITLE, URL, REPO, SOURCE_BRANCH, …). The status line reports ran, failed: <last stderr line>, or started if it is still going after two seconds. Commands show in the ? panel and the command palette.

The motivating example (in the README): on a pull request, ctrl+r opens a herdr tab in the current workspace and starts a Claude Code review of that PR.

How

• config: Command, the three kinds, ValidateCommands.
• ui/custom.go: the runner. It uses sh -c (cmd /S /C on Windows) in its own process group. stdin is /dev/null and stdout is dropped. stderr goes to an unlinked temp file rather than a pipe, so a command outlives boardwalk without dying of SIGPIPE, and a backgrounded child cannot hold up the result.
• ui/subject.go: eight views gain Subject(): the PR list, detail, diff and file views; the work item list and item; the build list and logs.
• ui/rootcommands.go: Root matches the key after the prompt, filter and armed-vote guards. A screen's own key always wins. The result goes to the view the command ran on, wherever it now sits in the stack. Startup refuses keys that cannot work: unparseable, reserved, list or viewport movement, ones every screen uses, and the palette key.
• Logs, PR detail and work item detail now show a StatusMsg error in red without marking the discussion as failed to load.

Values reach commands only as environment variables, never spliced into the command string, so a PR title full of shell syntax stays a title.

Design: docs/superpowers/specs/2026-10-06-custom-commands-design.md. Plan: docs/superpowers/plans/2026-10-06-custom-commands.md.

Testing

• go test ./..., go vet ./... and GOOS=windows go build ./... all pass.
• The runner is tested against a real sh. Tests cover the environment, failure output, a 10,000-line stderr flood, detaching from a long command, a background child holding stderr, and shell syntax in a value staying inert.
• Root tests cover dispatch, kind matching, built-in keys winning, an armed vote blocking the command, a result for a view no longer on top, and the help panel and palette.
• Startup check confirmed by hand: a config binding q exits at once with an error naming the file.
• Not yet done: pressing the key in a live TUI, and running anything on Windows (it is only compile-checked).

🤖 Generated with Claude Code

https://claude.ai/code/session_01Jn8iZy7cV652kj9axpyrUq