primus/eventemitter3

Health v2 · maintenance only

Adoption not part of the score

3538 stars · 236 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

EventEmitter3 is a high-performance JavaScript event emitter that is API-compatible with Node.js's built-in EventEmitter while also running in browsers. It is micro-optimized for speed, supports custom 'this' context for listeners without fn.bind, and is written in EcmaScript 3 so it works in very old browsers and Node versions.

Use cases

• fast event emitter for node.js
• event emitter library that works in the browser
• drop-in replacement for node EventEmitter with better performance
• lightweight pub/sub event bus for javascript
• event emitter with custom this context instead of fn.bind
• event system compatible with old browsers and node versions

When to choose

• You need maximum event emission throughput in Node.js or the browser
• You want a drop-in Node.js EventEmitter replacement that adds contextual binding and removes bind() overhead
• You must support very old browsers or Node versions since the code is EcmaScript 3

When to avoid

• You rely on Node.js domains or the newListener/removeListener lifecycle events
• You need setMaxListeners, getMaxListeners, prependListener, or prependOnceListener methods
• You expect an error to be thrown when emitting an 'error' event with no listeners

Facets

library · maturity stable

message-queue web-development frontend backend developer-tools browser bun cross-platform event-emitter pubsub event-bus publish-subscribe observer-pattern high-performance drop-in-replacement es3-compatible javascript nodejs electron deno

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