Chezmoi Dotfiles

Chezmoi Dotfiles Management

Overview

Provide expert guidance for managing dotfiles securely with chezmoi, focusing on security-first practices, multi-machine synchronization, and proper secrets management. Help users maintain well-organized, secure dotfiles repositories that follow industry best practices.

Core Capabilities:

• Initialize and configure chezmoi repositories with security defaults
• Safely add dotfiles while preventing secret exposure
• Implement age encryption for sensitive files
• Create templates for machine-specific configurations
• Audit dotfiles for security issues
• Troubleshoot chezmoi workflows

Security-First Workflow

Before ANY operation involving files, follow this security evaluation:

User wants to add/modify a file
    ↓
1. Does the file contain secrets?
   (API keys, passwords, tokens, private keys, credentials)
    ├─ YES → Go to step 2
    └─ NO → Check if it mixes secrets with public config → Go to step 3

2. File contains secrets:
   ├─ Is it a private key? → Use age encryption: `chezmoi add --encrypt`
   ├─ Can secrets be externalized? → Use templates + chezmoi.yaml
   └─ Should it be tracked at all? → Add to .chezmoiignore

3. File mixes public config and secrets:
   → Use templates to separate concerns
   → Store secrets in ~/.config/chezmoi/chezmoi.yaml (not committed)
   → Template example: {{ .git.email }} instead of hardcoded email

4. File is safe (no secrets):
   → Check .chezmoiignore patterns first
   → Use `chezmoi add` normally
   → Run `scripts/check_secrets.py` before committing

Security Checklist - Run Before Every Commit:

# 1. Scan for secrets
python3 ~/.local/share/chezmoi/scripts/check_secrets.py

# 2. Review what's being committed
cd ~/.local/share/chezmoi && git diff --cached

# 3. Verify .chezmoiignore is working
chezmoi managed | grep -E "(\.env|credentials|secret)"

Core Workflows

1. Initialize New Chezmoi Repository

When: First-time setup, creating new dotfiles repository

Steps:

# 1. Run initialization script (creates secure defaults)
bash scripts/init_chezmoi_repo.sh

# 2. Set up age encryption (recommended)
age-keygen -o ~/.config/chezmoi/key.txt

# Note the public key, then configure:
cat >> ~/.config/chezmoi/chezmoi.yaml << EOF
encryption: "age"
age:
  identity: "${HOME}/.config/chezmoi/key.txt"
  recipient: "age1..."  # Public key from key.txt
EOF

# 3. Add git remote
cd ~/.local/share/chezmoi
git remote add origin https://github.com/username/dotfiles.git

# 4. Add first dotfiles
chezmoi add ~/.bashrc ~/.zshrc

Script Available: scripts/init_chezmoi_repo.sh creates:

• .chezmoiignore with security defaults
• README.md with instructions
• .chezmoidata.yaml.template for custom variables
• Initial git commit

2. Adding Dotfiles

When: User wants to track a new configuration file

Security Decision Tree:

File type?
├─ Shell config (.bashrc, .zshrc) → Check for secrets → Add normally or template
├─ Git config (.gitconfig) → Template for email: `chezmoi add --template`
├─ SSH config → Template for host-specific configs
├─ SSH private key → `chezmoi add --encrypt ~/.ssh/id_ed25519`
├─ .env file → NEVER ADD - Add to .chezmoiignore
├─ Cloud credentials (.aws/credentials) → Encrypt or don't track
└─ Editor config (.vimrc, nvim/) → Usually safe to add normally

Commands:

# Regular file
chezmoi add ~/.bashrc

# Template file (for variables)
chezmoi add --template ~/.gitconfig

# Encrypted file (for secrets)
chezmoi add --encrypt ~/.ssh/id_ed25519

# Directory (recursive)
chezmoi add ~/.config/nvim

Always warn about:

• Never commit .env files with real secrets
• Private keys should be encrypted
• Files with mixed content should use templates

3. Managing Secrets

When: User needs to handle sensitive files

Three Approaches:

Option A: Age Encryption (Preferred for Keys)

# Add with encryption
chezmoi add --encrypt ~/.ssh/id_ed25519

# Edit encrypted file
chezmoi edit ~/.ssh/id_ed25519

# Result: Creates encrypted_id_ed25519.age in source

Use for:

• SSH private keys
• GPG private keys
• Certificate files

Option B: Templates + External Config (Preferred for Credentials)

# 1. Add as template
chezmoi add --template ~/.gitconfig

# 2. Edit to use variables
chezmoi edit ~/.gitconfig

# Content becomes:
# [user]
#   email = "{{ .git.email }}"
#   signingkey = "{{ .git.signingkey }}"

# 3. Store actual values in ~/.config/chezmoi/chezmoi.yaml (not committed)
data:
  git:
    email: "user@example.com"
    signingkey: "ABCD1234"

Use for:

• Git configuration with emails/keys
• API endpoints that vary by machine
• Configuration files with embedded tokens

Option C: Don't Track At All

# Add to .chezmoiignore
**/.aws/credentials
**/.env

Use for:

• Cloud provider credentials (retrieve from vault instead)
• Local development .env files
• Browser cookies/sessions

Security Reference: See references/security-checklist.md for comprehensive guidance.

4. Creating Templates

When: Configuration needs to vary by machine

Common Template Scenarios:

Git Config with Multiple Emails

# dot_gitconfig.tmpl
[user]
  name = "{{ .git.name }}"
{{- if eq .machine.type "work" }}
  email = "{{ .email.work }}"
{{- else }}
  email = "{{ .email.personal }}"
{{- end }}

SSH Config with Host-Specific Keys

# dot_ssh/config.tmpl
{{- if eq .machine.type "work" }}
Host github-work
  HostName github.com
  IdentityFile ~/.ssh/id_ed25519_work
{{- end }}

Shell RC with OS-Specific Settings

# dot_zshrc.tmpl
{{- if eq .chezmoi.os "darwin" }}
eval "$(/opt/homebrew/bin/brew shellenv)"
{{- else if eq .chezmoi.os "linux" }}
alias ls='ls --color=auto'
{{- end }}

Template Reference: See references/template-examples.md for comprehensive examples.

Data Configuration: Use assets/.chezmoidata.yaml.template as starting point.

5. Multi-Machine Setup

When: Syncing dotfiles to new machine

Setup Process:

# On new machine:
# 1. Install chezmoi
sh -c "$(curl -fsLS get.chezmoi.io)"

# 2. Initialize from repository
chezmoi init https://github.com/username/dotfiles.git

# 3. Configure machine-specific data
cp ~/.local/share/chezmoi/assets/.chezmoidata.yaml.template \
   ~/.config/chezmoi/chezmoi.yaml

# Edit for this machine:
# - Set machine.type (personal, work, server)
# - Configure email addresses
# - Set development tool preferences

# 4. Preview changes
chezmoi diff

# 5. Apply dotfiles
chezmoi apply -v

For Encrypted Files:

• Copy age key from secure location: ~/.config/chezmoi/key.txt
• Or regenerate and re-encrypt files for new machine

6. Security Audit

When: Regular maintenance, before sharing repository, after adding many files

Audit Checklist:

# 1. Run secret scanner
python3 scripts/check_secrets.py

# 2. Check git history for leaked secrets
cd ~/.local/share/chezmoi
git log -p | grep -E "api[_-]?key|password|secret" | head -20

# 3. Verify .chezmoiignore effectiveness
chezmoi managed | wc -l  # Should be reasonable
chezmoi managed | grep -E "(\.env|credentials|secret|password)"

# 4. List encrypted files
chezmoi status | grep "\.age$"

# 5. Review template security
grep -r "password\|secret\|key" ~/.local/share/chezmoi/*.tmpl

Security Reference: references/security-checklist.md contains comprehensive audit procedures.

7. Troubleshooting

Common Issues:

"File Not Updating After Edit"

# Check if managed
chezmoi managed | grep filename

# Check if ignored
cat $(chezmoi source-path)/.chezmoiignore | grep filename

# View diff
chezmoi diff ~/.filename

# Force re-add if needed
chezmoi add --force ~/.filename

"Template Not Rendering Correctly"

# Preview template output
chezmoi cat ~/.filename

# View available data
chezmoi data

# Test specific expression
chezmoi execute-template "{{ .variable }}"

"Encrypted File Won't Decrypt"

# Verify age key exists
ls ~/.config/chezmoi/key.txt

# Check chezmoi.yaml has encryption configured
cat ~/.config/chezmoi/chezmoi.yaml | grep -A3 "encryption"

# Test decryption
chezmoi cat ~/.ssh/id_ed25519

Essential Commands

Quick Reference (See references/chezmoi-commands.md for comprehensive guide):

# Initialize
chezmoi init [repo-url]

# Add files
chezmoi add ~/.bashrc
chezmoi add --template ~/.gitconfig
chezmoi add --encrypt ~/.ssh/id_ed25519

# Edit files
chezmoi edit ~/.bashrc
chezmoi edit --apply ~/.bashrc

# Apply changes
chezmoi diff          # Preview
chezmoi apply -v      # Apply with verbose output

# Sync with remote
chezmoi update -v     # Pull and apply

# Git operations
chezmoi git status
chezmoi git commit -m "message"
chezmoi git push

# Inspection
chezmoi status        # Show what would change
chezmoi managed       # List managed files
chezmoi cat ~/.file   # Show target content
chezmoi data          # Show template data

Proactive Security Guidance

Always provide these warnings when relevant:

1. Before adding .env files:

   ⚠️ Security Warning: .env files often contain secrets. Add to .chezmoiignore instead, or use templates with variables stored in non-committed chezmoi.yaml.

2. Before adding SSH keys:

   ⚠️ Security Warning: Use age encryption for private keys: chezmoi add --encrypt ~/.ssh/id_ed25519

3. Before adding mixed-content files:

   ⚠️ Security Note: This file contains both public config and secrets. Consider using a template with variables to separate concerns.

4. Before committing:

   ⚠️ Security Check: Run scripts/check_secrets.py to scan for accidentally included secrets before committing.

5. When suggesting .chezmoiignore patterns:

   Suggest running scripts/generate_chezmoiignore.py with relevant categories instead of manually typing patterns.

Using Bundled Resources

Scripts

scripts/check_secrets.py - Scan for potential secrets

# Scan default chezmoi source directory
python3 scripts/check_secrets.py

# Scan specific directory
python3 scripts/check_secrets.py /path/to/directory

Run before every commit to catch accidentally included secrets.

scripts/init_chezmoi_repo.sh - Initialize with security defaults

bash scripts/init_chezmoi_repo.sh

Creates .chezmoiignore, README, and git repository with secure defaults.

scripts/generate_chezmoiignore.py - Generate comprehensive ignore patterns

# Interactive mode with defaults
python3 scripts/generate_chezmoiignore.py

# Specific categories
python3 scripts/generate_chezmoiignore.py --categories python node macos

# All patterns
python3 scripts/generate_chezmoiignore.py --all

# List available categories
python3 scripts/generate_chezmoiignore.py --list

# Output to file
python3 scripts/generate_chezmoiignore.py --output ~/.local/share/chezmoi/.chezmoiignore

References

Load these into context when needed for detailed information:

• references/security-checklist.md - Comprehensive security practices, encryption setup, pre-commit checks, secret management strategies
• references/ignore-patterns.md - Extensive catalog of .chezmoiignore patterns organized by category (security, languages, OS, editors, etc.)
• references/template-examples.md - Practical template examples for common scenarios (Git config, SSH config, shell RC, AWS config, etc.)
• references/chezmoi-commands.md - Complete command reference with explanations of when and how to use each command

Assets

Provide these templates to users:

• assets/.chezmoiignore.template - Comprehensive starter ignore file with security-focused defaults
• assets/.chezmoidata.yaml.template - Template data configuration with examples for common variables
• assets/README.md.template - Professional README for documenting dotfiles repositories

Best Practices Summary

Always:

• ✅ Run security checks before committing
• ✅ Use age encryption for private keys
• ✅ Use templates for files with mixed public/secret content
• ✅ Maintain comprehensive .chezmoiignore
• ✅ Document why files are encrypted/templated
• ✅ Back up age encryption keys separately

Never:

• ❌ Commit .env files with real secrets
• ❌ Track browser storage or cookies
• ❌ Skip reviewing git diffs
• ❌ Share age encryption keys via repository
• ❌ Track cache or temporary directories
• ❌ Commit chezmoi.yaml if it contains secrets

Recommend:

• Use scripts/generate_chezmoiignore.py for comprehensive patterns
• Set up pre-commit hooks with scripts/check_secrets.py
• Regular security audits (quarterly)
• Meaningful commit messages
• Testing on multiple machines before finalizing templates