fastapi-redis-codes

fastapi-redis-codes is a cursor rule for Cursor from sebastien-le-paris/project-rules. It costs 0 tokens per session (655 once invoked), scanned A, original, Apache-2.0.

A set of instructions for building FastAPI services that use Redis, a fast in-memory data store, within microservices and serverless systems. It covers caching, background workers, gateways, retries, and service communication.

In plain words
What is it for?
It helps create FastAPI microservices with Redis-backed state or caching, API gateway integration, asynchronous jobs, retries, and serverless deployment patterns.
Why use it?
It guides designs that remain reliable when services communicate, traffic increases, requests fail, or work needs to run in the background.

Cursor rule for Cursor

Install

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.

agentmods
npx agentmods add rules/sebastien-le-paris/project-rules/fastapi-redis-codes
Clone the repo
git clone --depth 1 https://github.com/sebastien-le-paris/project-rules

Made for: Cursor.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for fastapi-redis-codes

README.md
[![agentmods](https://agentmods.dev/badge/rules/sebastien-le-paris/project-rules/fastapi-redis-codes.svg)](https://agentmods.dev/rules/sebastien-le-paris/project-rules/fastapi-redis-codes)
Your own site
<a href="https://agentmods.dev/rules/sebastien-le-paris/project-rules/fastapi-redis-codes"><img src="https://agentmods.dev/badge/rules/sebastien-le-paris/project-rules/fastapi-redis-codes.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 655 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What 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.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00655
Opus 5 $0.00000 $0.00328
Sonnet 5 $0.00000 $0.00131
Haiku 4.5 $0.00000 $0.00065

Measured 4d ago against content hash b9730ba0bc18, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

fastapi-redis-codes 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 4d 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.

.cursor/rules/fastapi-redis-codes.mdc · 55 lines

What it actually says


description: globs:

You are an expert in Python, FastAPI, microservices architecture, and serverless environments.

Advanced Principles

  • Design services to be stateless; leverage external storage and caches (e.g., Redis) for state persistence.
  • Implement API gateways and reverse proxies (e.g., NGINX, Traefik) for handling traffic to microservices.
  • Use circuit breakers and retries for resilient service communication.
  • Favor serverless deployment for reduced infrastructure overhead in scalable environments.
  • Use asynchronous workers (e.g., Celery, RQ) for handling background tasks efficiently.

Microservices and API Gateway Integration

  • Integrate FastAPI services with API Gateway solutions like Kong or AWS API Gateway.
  • Use API Gateway for rate limiting, request transformation, and security filtering.
  • Design APIs with clear separation of concerns to align with microservices principles.
  • Implement inter-service communication using message brokers (e.g., RabbitMQ, Kafka) for event-driven architectures.

Serverless and Cloud-Native Patterns

  • Optimize FastAPI apps for serverless environments (e.g., AWS Lambda, Azure Functions) by minimizing cold start times.
  • Package FastAPI applications using lightweight containers or as a standalone binary for deployment in serverless setups.
  • Use managed services (e.g., AWS DynamoDB, Azure Cosmos DB) for scaling databases without operational overhead.
  • Implement automatic scaling with serverless functions to handle variable loads effectively.

Advanced Middleware and Security

  • Implement custom middleware for detailed logging, tracing, and monitoring of API requests.
  • Use OpenTelemetry or similar libraries for distributed tracing in microservices architectures.
  • Apply security best practices: OAuth2 for secure API access, rate limiting, and DDoS protection.
  • Use security headers (e.g., CORS, CSP) and implement content validation using tools like OWASP Zap.

Optimizing for Performance and Scalability

  • Leverage FastAPI’s async capabilities for handling large volumes of simultaneous connections efficiently.
  • Optimize backend services for high throughput and low latency; use databases optimized for read-heavy workloads (e.g., Elasticsearch).
  • Use caching layers (e.g., Redis, Memcached) to reduce load on primary databases and improve API response times.
  • Apply load balancing and service mesh technologies (e.g., Istio, Linkerd) for better service-to-service communication and fault tolerance.

Monitoring and Logging

  • Use Prometheus and Grafana for monitoring FastAPI applications and setting up alerts.
  • Implement structured logging for better log analysis and observability.
  • Integrate with centralized logging systems (e.g., ELK Stack, AWS CloudWatch) for aggregated logging and monitoring.

Key Conventions

  1. Follow microservices principles for building scalable and maintainable services.
  2. Optimize FastAPI applications for serverless and cloud-native deployments.
  3. Apply advanced security, monitoring, and optimization techniques to ensure robust, performant APIs.

Refer to FastAPI, microservices, and serverless documentation for best practices and advanced usage patterns.

Changes

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.

  1. 4d ago First seen · 55 lines · 0 tokens per session scan A b9730ba0bc18

Subscribe to this mod's changes

fastapi-redis-codes is a cursor rule published in the GitHub repository sebastien-le-paris/project-rules (0 stars, last pushed 1y ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 655 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 2026-08-31.