We Benchmarked Our SSR Framework Against Next.js — Here's What We Found

We built Pareto, a lightweight streaming-first React SSR framework on Vite. Claims are cheap — so we built an automated benchmark suite that runs in CI on every PR, comparing Pareto against Next.js, React Router (Remix), and TanStack Start on identical hardware. What We Tested Four scenarios covering the most common SSR workloads: Static SSR — Page with inline data, no async loader. Pure SSR throughput. Data Loading — Loader with simulated 10ms DB query. SSR + data fetching overhead. Streaming SSR — defer() + Suspense with 200ms delayed data. Streaming pipeline efficiency. API / JSON — Pure JSON endpoint. Routing + serialization overhead. All benchmarks on GitHub Actions (Ubuntu, Node 22, 4 CPUs), using autocannon with 100 connections for 30 seconds. Throughput: Requests Per Second Scenario Pareto Next.js React Router TanStack Start Static SSR 2,224/s 3,328/s 997/s 2,009/s Data Loading 2,733/s 293/s 955/s 1,386/s Streaming SSR 247/s 236/s 247/s 247/s API / JSON 3,675/s 2,212/s 1,950/s