It provides a faster alternative to the standard Node.js EventEmitter through micro-optimization of code paths, while maintaining API compatibility with the built-in implementation.
The tool solves the problem of event handling overhead by stripping away less commonly used features and optimizing the remaining core functionality. It removes domain support, the newListener and removeListener events, and methods like setMaxListeners and prependListener. In exchange, it adds support for custom context binding on events, eliminating the need to use fn.bind for setting the this value during emission. The removeListener method also behaves differently, removing all matching listeners rather than just the first.
EventEmitter3 suits projects where performance matters and the removed features are not required. It works as a drop-in replacement for the standard EventEmitter in both Node.js and browser environments, written in ECMAScript 3 for broad compatibility with older platforms. The README does not compare it to other third-party event emitters, only to Node.js's built-in implementation.
The project maintains an active test suite that can be run with npm test, and includes benchmarks available after cloning the repository and installing dependencies in the benchmarks folder. The codebase is written in a way that supports very old JavaScript standards and browser versions, indicating a commitment to broad compatibility across environments.
