Yaffle/EventSource

Health v2 · maintenance only

Adoption not part of the score

2183 stars · 335 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

A JavaScript polyfill for the EventSource (Server-Sent Events) API, providing support for older browsers like IE 8-10 and adding features such as custom headers and cross-domain requests. It is distributed as the 'event-source-polyfill' npm package and works with bundlers like webpack and browserify.

Use cases

• consume server-sent events in browsers without native EventSource support
• add custom headers to EventSource requests for authentication
• use SSE with cross-domain (CORS) requests in legacy browsers
• support IE 10 and older browsers for real-time event streams
• integrate SSE into Angular or Ionic applications via polyfills
• send Last-Event-ID for stream reconnection in browsers lacking header support

When to choose

• you need Server-Sent Events in legacy browsers like IE 8-10
• you need custom headers or Last-Event-ID query parameter support with EventSource
• you want cross-domain SSE with simple server-side requirements

When to avoid

• your target browsers all support native EventSource
• you need bidirectional communication (use WebSockets instead)
• you need to support Android Browser or Opera Mini
• the maintainer explicitly discourages using this library for new projects

Facets

library · maturity maintenance

http-client websocket web-development frontend apis browser cross-platform server-sent-events eventsource polyfill sse real-time javascript

Member repositories

For agents

markdown · JSON · MCP: product_card(name="Yaffle/EventSource")