Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add rules/levifig/rails-instructions/deploymentgit clone --depth 1 https://github.com/levifig/rails-instructionsWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00000 | $0.00982 |
| Opus 5 | $0.00000 | $0.00491 |
| Sonnet 5 | $0.00000 | $0.00196 |
| Haiku 4.5 | $0.00000 | $0.00098 |
Grade A, and why
deployment scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 178 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Rails Deployment with Kamal
Core Philosophy
- Deploy containerized Rails applications without complexity
- Use Kamal for zero-downtime deployments
- Keep deployment configuration simple and version controlled
- Leverage Docker without becoming a Docker expert
- Deploy anywhere with SSH access
Kamal Principles
- One command deployments with automatic rollback
- Built-in health checks and rolling updates
- Integrated secret management
- No Kubernetes complexity needed
- Direct SSH-based deployment to servers
Configuration Strategy
- Keep all deployment config in
config/deploy.yml - Use environment-specific settings wisely
- Store secrets securely with Kamal's encryption
- Version control deployment configuration
- Document server requirements clearly
Server Prerequisites
- Ensure servers have Docker installed
- Configure SSH access for deployment user
- Set up firewall rules appropriately
- Prepare SSL certificates if needed
- Verify sufficient disk space and memory
Environment Management
- Use Kamal's built-in environment variable handling
- Separate secrets from non-sensitive configuration
- Use
.envfiles for local development only - Leverage Rails credentials for application secrets
- Keep production passwords out of version control
Container Strategy
- Build minimal production Docker images
- Use multi-stage builds to reduce size
- Install only production dependencies
- Configure proper health check endpoints
- Set appropriate resource limits
Database Configuration
- Use managed databases when possible
- Configure connection pooling appropriately
- Set up automated backups
- Use read replicas for scaling
- Handle database migrations carefully
Asset Management
- Precompile assets during Docker build
- Use CDN for asset delivery
- Configure proper cache headers
- Compress assets appropriately
- Handle asset versioning correctly
Health Checks
- Implement
/upendpoint for health monitoring - Check database connectivity
- Verify background job processing
- Monitor external service dependencies
- Return appropriate status codes
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2d ago First seen · 178 lines · 0 tokens per session scan A b07072df400c
deployment is a cursor rule published in the GitHub repository levifig/rails-instructions (54 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 982 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other cursor rules, from other repositories
pytest-integration-tests
Below is an example test. Notice the following.
python-app
Cursor rule "python-app" from iloveitaly/llm-ide-rules, covering python app, factories and database & orm.
react
Cursor rule "react" from iloveitaly/llm-ide-rules, covering react, mock data, react hook form and styling.
creating-cursor-rules
Meta-rule for creating effective Cursor IDE rules with best practices, patterns, and examples.
react-router
Cursor rule "react-router" from iloveitaly/llm-ide-rules, covering react router, loading mock data, how to use clientloader and loading backend data.
pytest-tests
Below is an example test, you'll notice the following.