Show HN: Proa – a Rust web framework with fast SSR and multi-target rendering

Proa is a batteries-included Rust web framework that centers a typed component model capable of rendering to multiple targets (HTML, Markdown, etc.) from a single component implementation. Components implement target-specific render traits and receive a shared, request-scoped WebContext that exposes typed loaders, route state, response metadata, and streaming controls. The framework provides streaming SSR with ordered or out-of-order Suspense boundaries, server-first interactivity via RSJS islands (typed signals and handlers compiled to tiny per-island JS), and a component catalog (Proa UI) with live examples and source in the application repo so the Rust compiler validates changes before deploy.

Proa emphasizes raw server-render performance and low operational cost. Benchmarks show median server-render latency around 5.56 ms and claim much higher render throughput than React, with example HTTP capacity of 16,100 product-grid responses/sec at ~9.4 MiB peak memory and sustained Suspense streaming near 5,000 rps before queueing. Security and accessibility checks run at build time, and adoption is incremental: run Axum-native or call Proa over FFI from Node, Go, Python, or Ruby and route a single route to Proa while leaving the rest of the stack intact. The framework ships server-rendered HTML by default and only compiles small client runtimes for interactive islands.