Build realtime apps in minutes — without WebSockets complexity.
A lightweight, developer-friendly alternative to Pusher and Ably. Powered by Server-Sent Events (SSE). Fast setup, predictable pricing, and zero client library required.
// Connect from any browser
const stream = new EventSource(
"https://api.sse-server.com/stream?key=YOUR_KEY"
);
stream.onmessage = (msg) => {
console.log("event:", msg.data);
};# Send an event from your backend
curl -X POST https://api.sse-server.com/send \
-H "Authorization: Bearer YOUR_KEY" \
-d '{"event":"update","data":"hello"}'Why developers choose SSE-Server
Simple API, low overhead, and no infrastructure to maintain.
Native browser support
Connect with a single EventSource call. No custom
clients, no reconnect logic, no complex stateful WebSocket
code.
3–5 ms overhead
SSE keeps a single, long-lived HTTP connection. Low latency, low overhead, and fewer moving parts than WebSocket setups.
No per-connection surprises
Simple, transparent pricing. Ideal for indie projects, SaaS, agencies, and internal tools that need realtime without enterprise pricing.
Stream over plain HTTP
SSE uses standard HTTP. See traffic in your browser dev tools or
with curl. Debug faster and ship with less friction.
We handle the scaling
You publish events via a simple HTTP API. We handle fan-out, concurrency, and scaling across clients.
Generous free tier
Start free with a generous allocation. Build your prototype, test at scale, and pay only when you're ready. Students get special offers— email us.
A predictable alternative to Pusher & Ably
Stop paying for per-connection surprises. SSE-Server keeps things simple.
| Feature | SSE-Server | Pusher / Ably |
|---|---|---|
| Browser support | Native EventSource | Custom client library |
| Complexity | Very low | Medium / high |
| Latency | 3–5 ms overhead | 3–5 ms overhead |
| Pricing | Predictable, flat | Per-connection, can spike |
| Debugging | Simple (HTTP-based) | Harder (binary/event protocols) |
| Setup time | ~2 minutes | 20–40 minutes |
Try it now — it takes 2 minutes
Create an API key, paste the example, and send your first realtime event. No credit card required to start.
✓ Generous free plan • ✓ Students welcome • ✓ Special offers available
Students? Email [email protected] for our special student offer.
What you can build in minutes
If your app needs realtime updates, SSE-Server is a great fit.
- Realtime dashboards and admin panels
- Notification feeds and activity streams
- IoT telemetry and device monitoring
- Monitoring, alerts, and log streaming
- Multiplayer games
- Chats and support widgets
- Financial tickers and live quotes
- Internal tools that need realtime state
Secure, simple, and built for developers
SSE is simple by design. We add the security and reliability you expect in production.
HTTPS by default
All traffic runs over HTTPS. Tokens and keys protect your streams. You can also add your own application-layer encryption if required.
Optional end-to-end encryption
For extra privacy, encrypt payloads client-side using libraries like TweetNaCl.js. SSE-Server simply transports your encrypted data without inspecting it.
Made for builders
Clear docs, minimal concepts, and examples you can copy into your existing stack. Spend time on features, not plumbing.
Why SSE is enough for 90% of realtime apps
Most realtime apps don’t need full bidirectional WebSockets. They need 1→many streaming, low latency, and reliability.
- One-way streaming from server to many clients
- Native browser support via
EventSource - Automatic reconnect built-in
- Easy scaling and load balancing
- No connection juggling or stateful socket servers
- Perfect for dashboards, feeds, alerts, and telemetry
- Less complexity → fewer bugs
- Works alongside normal HTTP APIs