Celeris vs Pusher
An honest comparison of Celeris and Pusher: throughput, billing model, and when each is the right choice.
Pusher has a clean developer experience and was one of the first to popularize managed WebSockets. Where it struggles is throughput and billing predictability at scale.
TL;DR
Choose Celeris if:
- You need sustained high message throughput
- Connection-based billing from Pusher is hitting you on traffic spikes
- You want binary messaging (MessagePack, Protobuf)
- You want data in your own infrastructure (BYOD, coming soon)
- Predictable, usage-based pricing matters more than a simpler API
Choose Pusher if:
- You need a simple, fast integration and throughput isn't critical
- Your team already knows Pusher and migration cost is high
- You need Pusher Beams (push notifications) specifically
- Your connection counts are modest and predictable
The billing model difference
Pusher charges on peak concurrent connections per plan, then messages on top. Connection-based billing is unpredictable: a traffic spike costs you even if it's brief. Celeris charges for connection minutes, so you only pay for time connections are actually open.
Celeris billing:
- Pay per connection minute, not peak concurrent connections
- Spikes don't permanently bump your tier
- 10-year billing option for stable workloads
Pusher billing:
- Priced on concurrent connections (plan limit), not usage
- Spike to 500 connections on the 100-connection plan = upgrade required
- Not built for sustained high message rates
Feature comparison
| Feature | Celeris | Pusher |
|---|---|---|
| Throughput (benchmarked) | High-throughput, Kafka-backed | Not published |
| Binary messaging | ✓ | — |
| Kafka-backed ordering | ✓ | — |
| Billing model | Usage-based (minutes) | Connection-tier based |
| BYOD data export | Coming soon | — |
| 10-year recurring pricing | ✓ | — |
| Free tier | ✓ | ✓ |
| Multi-region | US and EU regions with global routing | Limited |
| Raw WebSocket compatible | ✓ | Limited |
| Push notifications | — | ✓ |
| Dashboard message testing | ✓ | ✓ |
The honest take
What Pusher does well: Pusher has excellent developer experience and a large ecosystem. Getting a basic WebSocket connection working is fast. Their Channels product is mature and well-documented.
Where Celeris is different: Pusher wasn't built for sustained high-throughput workloads. Binary-first messaging and Kafka-backed ordering don't exist in Pusher.
Who should use Pusher: If you have modest throughput requirements and want the fastest possible integration with minimal ops, Pusher works fine. If you're approaching Pusher's limits or billing is becoming unpredictable, Celeris is worth evaluating.