grw—lab Studio

General + Free · v0.1.0

Shared Server Deploy

Change one site on a shared cPanel, CWP, Plesk or Apache server without breaking its neighbours: discover, back up, test, reload, verify.

  1. 01

    Add the catalog

    Open Claude Code and paste this line. Do this once. If you already added grw—lab for another skill, skip it.

    $ /plugin marketplace add grw-lab/skills

  2. 02

    Install Shared Server Deploy

    Paste this second line. It installs Shared Server Deploy and leaves the other skills out.

    $ /plugin install shared-server-deploy@grw-lab

Every skill instead: use /plugin install grw-skills@grw-lab as line 2. On claude.ai, zip the shared-server-deploy folder and upload it in Settings, then Capabilities, then Skills. In Cursor, point the agent at shared-server-deploy/SKILL.md.

View on GitHubRead as Markdown

What it does

Shared Server Deploy teaches your agent to change one site on a server that hosts many, without breaking the others. It discovers the setup read-only, backs up what it will touch, keeps every edit inside the site you named, tests the config before a graceful reload, and then checks that every neighbouring site still answers the way it did before.

It comes from a real deploy on a CWP server running a dozen client sites, Node apps, mail, and a control panel. Every trap in it is one we hit or nearly hit.

When to use it

  • You ask an agent to deploy, add PHP, edit a vhost or .htaccess, or fix permissions on a server that also runs other sites.
  • The server uses cPanel, CWP, Plesk, DirectAdmin, or plain Apache or Nginx.
  • You want a record of what changed and a one-line rollback.

It is not for containers or platforms like Vercel, where each app is already isolated.

Install

This installs shared-server-deploy only. The other skills stay out.

  1. Open Claude Code.
  2. Paste line 1 and press Enter. This adds the catalog. Do it once, then skip it next time.
  3. Paste line 2 and press Enter. This installs this skill.
/plugin marketplace add grw-lab/skills
/plugin install shared-server-deploy@grw-lab

Claude confirms the install in the chat. The next message can use the skill.

Every skill instead: keep line 1, and use this as line 2:

/plugin install grw-skills@grw-lab

On claude.ai, zip the shared-server-deploy folder and upload it in Settings → Capabilities → Skills.

In Cursor or another agent, point it at shared-server-deploy/SKILL.md.

Usage

  • "Deploy this folder to tools.example.com. The server has other sites, only touch that one."
  • "PHP returns 500 on my subdomain. Find out why without changing anything yet."
  • "Add a security header to example.com's vhost and make sure nothing else breaks."
  • "Before you reload Apache, show me which sites live on this box."

Example

You ask: "Enable PHP for tools.example.com. Be careful, this server has other client sites."

The agent runs discovery and finds the docroot is nested inside the main site's WordPress folder, PHP runs through suPHP, and the subdomain's vhost has no user mapping. It then:

  1. Records the status of all sites on the box (all 200).
  2. Backs up the two vhost files to /root/deploy-backups/tools.example.com/20261008T101320Z/.
  3. Adds only the user mapping block, copied from the main site's vhost.
  4. Runs apachectl -t (Syntax OK) and a graceful reload.
  5. Re-checks every site: all still 200. PHP on the subdomain now runs as the site user.
  6. Reports the change, the backup path, and the rollback command.

What's inside

File Purpose
SKILL.md The five rules, the step-by-step workflow, rollback, and a table of traps that cause outages.
scripts/discover.sh Read-only report: OS, panel, web server, ports, PHP handler, vhost files, docroot owner, .htaccess chain, other domains.
scripts/neighbours.sh Saves every site's HTTP status before a change and compares after. Exits 1 if anything changed.
references/panels.md Where CWP, cPanel, Plesk, DirectAdmin, and plain Apache or Nginx keep vhosts, logs, and safe custom config.
references/htaccess-inheritance.md How a parent .htaccess leaks into a nested docroot, and how to stop it.

FAQ

Does it need root? Discovery mostly works without root. Editing vhosts and reloading Apache needs root or sudo. The skill runs site builds as the site user, not root.

Will the control panel overwrite the change? Sometimes. The skill checks which panel you run and prefers its include folder or custom-config hook. references/panels.md lists them.

Does it restart the web server? No. It only uses a graceful reload, after the config test passes. A restart drops live connections on every site.

What if a neighbour breaks anyway? neighbours.sh after exits with an error and the agent stops, shows the table, and offers the rollback command from the backup it made first.