How do I install the NestJS Real-Time skill?

Run npx skillmds add majiayu000/nestjs-real-time in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

What does the NestJS Real-Time skill do?

WebSocket and SSE selection strategies and scaling. It is listed under Coding & Dev Tools on SkillMD.

Is NestJS Real-Time safe to use?

This skill has not completed SkillMD's automated safety review yet. Capability flags: makes network calls. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with NestJS Real-Time?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is NestJS Real-Time free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published NestJS Real-Time?

majiayu000 (@majiayu000) published this skill. Their other Agent Skills are listed on their SkillMD profile.

NestJS Real-Time by majiayu000 — Agent Skill

Name: NestJS Real-Time
Rating: 4.2 (5 reviews)
Author: majiayu000

File contents

Real-Time & WebSockets

Priority: P1 (OPERATIONAL)

WebSocket and real-time communication patterns with NestJS.

WebSockets (Bi-directional): Use for Chat, Multiplayer Games, Collaborative Editing.
- High Complexity: Requires custom scaling (Redis Adapter) and sticky sessions (sometimes).
Server-Sent Events (SSE) (Uni-directional): Use for Notifications, Live Feeds, Tickers, CI Log streaming.
- Low Complexity: Standard HTTP. Works with standard Load Balancers. Easy to secure.
- NestJS: Use @Sse('route') returning Observable<MessageEvent>.
Long Polling: Use only as a fallback or for extremely low-frequency updates (e.g., job status check every 10m).
- Impact: High header overhead. Blocks threads if not handled carefully.

WebSockets Implementation

Socket.io: Default choice. Features "Rooms", "Namespaces", and automatic reconnection. Heavy protocol.
Fastify/WS: Use ws adapter if performance is critical (e.g., high-frequency trading updates) and you don't need "Rooms" logic.

Scaling (Critical)

WebSockets: In K8s, a client connects to Pod A. If Pod B emits an event, the client won't receive it.
- Solution: Redis Adapter (@socket.io/redis-adapter). Every pod publishes to Redis; Redis distributes to all other pods.
SSE: Stateless. No special adapter needed, but be aware of Connection Limits (6 concurrent connections per domain in HTTP/1.1; virtually unlimited in HTTP/2).
- Rule: Must use HTTP/2 for SSE at scale.

Security

Handshake Auth: Standard HTTP Guards don't trigger on Ws connection efficiently.
- Pattern: Validate JWT during the handleConnection() lifecycle method. Disconnect immediately if invalid.
Rate Limiting: Sockets are expensive. Apply strict throttling on "Message" events to prevent flooding.

Architecture

Gateway != Service: The WebSocketGateway should only handle client comms (Join Room, Ack message).
- Rule: Delegate business logic to a Service or Command Bus.
Events: Use AsyncApi or SocketApi decorators (from community packages) to document WS events similarly to OpenAPI.

---name: nestjs-real-timedescription: WebSocket and SSE selection strategies and scaling.--- # Real-Time & WebSockets ## **Priority: P1 (OPERATIONAL)** WebSocket and real-time communication patterns with NestJS. - **WebSockets (Bi-directional)**: Use for Chat, Multiplayer Games, Collaborative Editing. - _High Complexity_: Requires custom scaling (Redis Adapter) and sticky sessions (sometimes). - **Server-Sent Events (SSE) (Uni-directional)**: Use for Notifications, Live Feeds, Tickers, CI Log streaming. - _Low Complexity_: Standard HTTP. Works with standard Load Balancers. Easy to secure. - _NestJS_: Use `@Sse('route')` returning `Observable<MessageEvent>`. - **Long Polling**: Use **only** as a fallback or for extremely low-frequency updates (e.g., job status check every 10m). - _Impact_: High header overhead. Blocks threads if not handled carefully. ## WebSockets Implementation - **Socket.io**: Default choice. Features "Rooms", "Namespaces", and automatic reconnection. Heavy protocol. - **Fastify/WS**: Use `ws` adapter if performance is critical (e.g., high-frequency trading updates) and you don't need "Rooms" logic. ## Scaling (Critical) - **WebSockets**: In K8s, a client connects to Pod A. If Pod B emits an event, the client won't receive it. - **Solution**: **Redis Adapter** (`@socket.io/redis-adapter`). Every pod publishes to Redis; Redis distributes to all other pods. - **SSE**: Stateless. No special adapter needed, but be aware of **Connection Limits** (6 concurrent connections per domain in HTTP/1.1; virtually unlimited in HTTP/2). - **Rule**: Must use **HTTP/2** for SSE at scale. ## Security - **Handshake Auth**: Standard HTTP Guards don't trigger on Ws connection efficiently. - **Pattern**: Validate JWT during the `handleConnection()` lifecycle method. Disconnect immediately if invalid. - **Rate Limiting**: Sockets are expensive. Apply strict throttling on "Message" events to prevent flooding. ## Architecture - **Gateway != Service**: The `WebSocketGateway` should **only** handle client comms (Join Room, Ack message). - **Rule**: Delegate business logic to a Service or Command Bus. - **Events**: Use `AsyncApi` or `SocketApi` decorators (from community packages) to document WS events similarly to OpenAPI.

Frequently asked questions