Mac Audit

Purpose

Audit the macOS development environment for drift, security issues, and cleanup opportunities. Compares current state against the declared Brewfile and AUDIT.md project requirements. Produces a markdown report with pass/warn/fail indicators.

Run quarterly (or after major environment changes) to catch drift before it accumulates.

Arguments

• No arguments — run all 8 checks
• --section <name> — run only one section (brew-drift, orphans, security, versions, services, disk, shell, deferred)
• --deferred-only — only check deferred item readiness (quick check)

Configuration paths

BREWFILE=~/Developer/projects/macbook-clean/Brewfile
AUDIT_MD=~/Developer/projects/macbook-clean/AUDIT.md

Output format

Print a markdown report with a timestamp header and sections for each category. Use these indicators:

• PASS — healthy, no action needed
• WARN — not broken but worth investigating
• FAIL — needs attention

Example:

## Mac Environment Audit — 2026-02-12

### 1. Brew Drift
- PASS: 0 formulae installed but not in Brewfile
- WARN: 2 formulae in Brewfile but not installed (postgresql@16, gitleaks)

Checks to perform

Run each check inline using Bash commands. Do NOT create or depend on external scripts — keep the skill self-contained.

1. Brew Drift

Goal: Detect packages that have been installed ad-hoc (not declared in Brewfile) or declared but missing.

Steps:

1. Read the Brewfile at ~/Developer/projects/macbook-clean/Brewfile
2. Extract all formula names (lines starting with brew ") and cask names (lines starting with cask ")
3. Run brew leaves to get currently installed top-level formulae
4. Run brew list --cask to get installed casks
5. Compare:
   • Installed but not in Brewfile — potential orphans or undeclared additions
   • In Brewfile but not installed — missing tools (maybe not yet installed, or removed accidentally)
6. Run brew bundle check --file=~/Developer/projects/macbook-clean/Brewfile for the official check
7. Report results with PASS/WARN/FAIL

2. Orphan Detection

Goal: Find formulae that nothing depends on and no project needs.

Steps:

1. For each formula found in check 1 as "installed but not in Brewfile":
   • Run brew uses --installed <formula> to see if any installed formula depends on it
   • Cross-reference against known project requirements (Section 8 of AUDIT.md)
2. Flag formulae with 0 dependents AND no project need as orphan candidates
3. Report each orphan candidate with its status

3. Security Hygiene

Goal: Detect exposed secrets in environment and shell config.

Steps:

1. Run env | grep -iE 'token|secret|key|password' and review results
   • Filter out known-safe entries (PATH, HOMEBREW keys, SSH_AUTH_SOCK, etc.)
   • Flag anything that looks like an actual secret value
2. Search ~/.zshrc for hardcoded credentials:
   • grep -inE '(token|secret|password|api_key)\s*=' ~/.zshrc
3. Search ~/.zprofile for hardcoded credentials:
   • grep -inE '(token|secret|password|api_key)\s*=' ~/.zprofile
4. Check for .env files outside project directories:
   • find ~ -maxdepth 2 -name '.env' -not -path '*/Developer/projects/*' -not -path '*/.claude/*' 2>/dev/null
5. Report PASS if clean, FAIL if secrets found

4. Version Health

Goal: Verify runtime versions match project requirements.

Steps:

1. Check Node.js:
   • node --version — should be v22.x (project requirement)
   • which -a node — NVM path should come first, should show 1-2 entries (not more)
2. Check Python:
   • python3 --version — should be 3.13.x
   • which -a python3 — should show 1-2 entries (not 4)
3. Check for deprecated Homebrew formulae:
   • brew info --json=v2 --installed | jq '[.formulae[] | select(.deprecated == true) | .name]'
4. Check for outdated critical tools:
   • brew outdated --json=v2 | jq '[.formulae[].name] | length' — report count
5. Report PASS/WARN/FAIL per runtime

5. Service Health

Goal: Detect services that shouldn't be running, or zombie LaunchAgents.

Steps:

1. Run brew services list to get all Homebrew-managed services
2. For each running service: check if it has a project need (mongodb-community for hello-mern, postgresql@16 for hello-nean)
3. Flag running services with no project need as WARN
4. Check for LaunchAgent plists that exist but whose service is not running:
   • ls ~/Library/LaunchAgents/ 2>/dev/null | grep homebrew
   • Cross-reference against brew services list — if a plist exists but service is stopped/error, flag as zombie
5. Report results

6. Disk Usage

Goal: Flag large caches and scattered node_modules.

Steps:

1. Check sizes of key directories (use du -sh, suppress errors):
   • /opt/homebrew
   • ~/.npm
   • ~/Library/Caches/Homebrew
   • ~/Library/Caches/pip
   • ~/.nvm
   • ~/.pnpm-store (if exists)
2. Flag any cache over 1 GB as WARN
3. Check for node_modules directories outside ~/Developer/projects/:
   • find ~ -maxdepth 4 -name node_modules -type d -not -path '*/Developer/projects/*' -not -path '*/.nvm/*' 2>/dev/null
4. Report findings with sizes

7. Shell Config Health

Goal: Detect PATH and config issues that cause confusion.

Steps:

1. Check for duplicate PATH entries:
   • echo $PATH | tr ':' '\n' | sort | uniq -d
2. Check for non-existent directories in PATH:
   • echo $PATH | tr ':' '\n' | while read -r d; do [ ! -d "$d" ] && echo "$d"; done
   • Exclude known Apple system bootstrap paths (/var/run/com.apple.security.cryptexd/)
3. Check for duplicate aliases in ~/.zshrc:
   • grep '^alias ' ~/.zshrc | awk -F= '{print $1}' | sort | uniq -d
4. Check if ~/.profile exists and is empty (pointless file)
5. Check if ~/.bash_profile exists (leftover from bash)
6. Report PASS/WARN per finding

8. Deferred Item Readiness

Goal: Check whether items deferred during remediation are now safe to remove.

For each deferred item, run the specified check and report status:

Report for each item:

• SAFE TO REMOVE — condition met, dependents list is empty (or service conditions met)
• NOT YET — condition not met; list what still depends on it
• CHANGED — dependent count differs from expected baseline (worth investigating)

Expected baselines (from initial audit):

• node: 4 dependents (eslint, mongodb-community, mongosh, prettier)
• python@3.14: 1 dependent (semgrep)
• icu4c@76: 6 dependents (eslint, maven, openjdk, openjdk@11, postgresql@14, prettier)
• icu4c@77: 8 dependents (composer, libpq, mysql@8.0, openjdk@17, openjdk@21, opensearch, php, php@8.1)
• postgresql@14: running via LaunchAgent

After the audit

1. Present the full report to the user
2. If any FAIL items exist, recommend immediate action
3. If any deferred items show SAFE TO REMOVE, ask if the user wants to proceed with removal
4. If orphan candidates are found, ask if they should be added to the Brewfile (intentional) or uninstalled (not needed)
5. Suggest updating the Brewfile if drift is detected