Inngest Realtime

Stream updates from durable Inngest functions to live UIs. Use channels and topics to broadcast progress, render workflow execution as it happens, or build bi-directional human-in-the-loop flows.

These skills are focused on TypeScript. For Python or Go, refer to the Inngest documentation for language-specific guidance. Core concepts apply across all languages.

⚠ CRITICAL: v3 vs v4 package selection

Realtime in Inngest v4 lives at the SDK subpath inngest/realtime. The standalone @inngest/realtime npm package is a v3-era package and is NOT compatible with inngest@4.x. If your project is on v4 (the npm default), do not install @inngest/realtime. Use the imports below.

Symptoms of using the wrong package on v4: TypeError: Cls is not a constructor on every PUT /api/inngest, 401 on subscription tokens, type incompatibility on new Inngest({ middleware: [...] }). Verify your package.json shows "inngest": "^4.x" before reading further.

Prerequisites

• Inngest v4 SDK installed (npm install inngest) — see the inngest-setup skill
• INNGEST_DEV=1 set in .env.local for local development (without it, the SDK demands cloud signing keys and 401s on token requests)
• Local Inngest dev server running (npx inngest-cli@latest dev)
• Optional: zod for schema validation on topics