Zephyr Events – A 2KB TypeScript event emitter that's race-condition safe

I built a tiny event emitter that fixes a bug most people don't know they have: if a handler calls off() on itself during emit, the next handler gets skipped. EventEmitter3, Node's built-in EventEmitter, and mitt all have this problem. Zephyr Events uses snapshot-based iteration so handlers can subscribe, unsubscribe, or clear listeners mid-emit without side effects. If you don't need that safety, there's a zephyrEventsFast mode that's up to 82% faster. 1.9KB, zero dependencies, tree-shakeable Full TypeScript generics with strict handler signatures Wildcard listeners, shared handler maps, unsubscribe functions ESM, CommonJS, and UMD builds import zephyrEvents from ' zephyr-events ' ; type Events = { ' user:login ' : { id : number ; name : string } ' error ' : Error } const emitter = zephyrEvents < Events > (); const unsub = emitter . on ( ' user:login ' , ( user ) => { console . log ( `Welcome, ${ user . name } ` ); }); emitter . emit ( ' user:login ' , { id : 1 , name : ' Alice ' });