Modal launches serverless Servers for low-latency HTTP, WebSocket and gRPC traffic

Modal launched Servers, a regionalized autoscaling pool of HTTP server replicas for HTTP, WebSocket and gRPC traffic aimed at latency-sensitive workloads such as LLM inference for interactive agents. Modal says it cut p50 latency from 39ms to 6ms by keeping control-plane lookups and queueing off the request path, so clients get a 503 when no replica is available and must handle load shedding in the application. The routing layer runs on AWS EKS with Envoy at the edge and Modal's in-house Rust proxy fprs, built on Cloudflare's pingora, handling domain association and load balancing, with config read from Spanner and cached in memory.