Honestly, Fusillade started as a question I couldn't shake: why hasn't this been done already? Every load testing tool I reached for made the same trade-off, they'd blur your network latency with their own scripting overhead, so the p99 you were staring at was partly the tool's p99, not your service's. And if I wanted HTTP/2, WebSocket, gRPC, MQTT, AMQP, SSE, or a real browser, that was a different tool. So I started building it myself, on my spare time. The idea was simple: - A Rust engine on real OS threads with blocking I/O, so latency stays predictable and metrics measure network time only, never script execution. - Write your tests in JavaScript or TypeScript, with full IDE autocomplete and zero runtime cost. - One binary for every protocol, plus record/replay, HAR import, and scaling out to a cluster when you need it.

Fusillade

Rust based load testing tool using js for scripting

Rust based load testing tool using js for scripting