Rari

<a href="https://rari.build" target="_blank"> <picture> <source media="(prefers-color-scheme: dark)" srcset=".github/assets/rari-dark.svg"> <source media="(prefers-color-scheme: light)" srcset=".github/assets/rari-light.svg"> <img alt="rari" src=".github/assets/rari-light.svg" width="200"> </picture> </a>

Runtime Accelerated Rendering Infrastructure

rari is a React Server Components framework running on a Rust runtime. It has three layers: a Rust runtime (HTTP server, RSC renderer, and router with embedded V8), a React framework (app router, server actions, streaming/Suspense), and a build toolchain (Rolldown-powered Vite bundling, tsgo type checking). You write standard React — the runtime underneath is Rust instead of Node.

With proper app router support, true server-side rendering, and correct RSC semantics, rari delivers 44.9x higher throughput and 8.7x faster response times than Next.js.

Features

• App Router - File-based routing with layouts, loading states, and error boundaries
• True Server-Side Rendering - Pre-rendered HTML with instant hydration
• React Server Components - Server components by default, client components when you need them
• Rust-powered runtime - HTTP server, RSC renderer, and routing written in Rust with embedded V8
• Zero-config setup - Works out of the box with pre-built binaries
• Hot module reloading - Instant feedback during development
• node_modules support - Standard npm package resolution, unlike most Rust-based JS runtimes
• TypeScript-first - Full type safety across server/client boundary
• Cross-platform - Supports macOS, Linux, and Windows
• Streaming SSR - Progressive rendering with Suspense boundaries
• Loading States - Automatic loading skeletons during navigation

Quick Start

Create a new rari application in seconds:

npm create rari-app@latest my-app
cd my-app
npm run dev

That's it! Your app will be running at http://localhost:5173.

Visit rari.build/docs for complete documentation, guides, and examples.

Documentation

Read the full documentation to learn more about:

• Getting started with rari
• App Router and file-based routing
• Server Components and Client Components
• Server Actions and data mutations
• Streaming SSR and Suspense
• Deployment and production optimization

Why rari?

Performance That Matters

• 8.7x faster response times - 0.14ms vs 1.22ms average response
• 44.9x higher throughput - 67,208 req/sec vs 1,496 req/sec under load
• 45.2x faster latency under load - 0.74ms vs 33.44ms average latency
• 56% smaller bundles - 281 KB vs 634 KB client JavaScript
• 2.8x faster builds - 1.35s vs 3.75s production builds

Developer Experience

• App Router - File-based routing with automatic code splitting
• Zero configuration - Create projects instantly with create-rari-app
• Hot module reloading - See changes instantly during development
• Full TypeScript support - Complete type safety across server/client boundary
• Correct RSC semantics - Server components by default, 'use client' for interactivity
• Cross-platform - Works on macOS, Linux, and Windows

Performance

rari delivers exceptional performance that significantly outperforms traditional React frameworks:

Head-to-Head Comparison vs Next.js

Benchmarks last updated: March 25, 2026

Response Time (Single Request): | Metric | rari | Next.js | Improvement | |--------|------|---------|-------------| | Average | 0.14ms | 1.22ms | 8.7x faster | | P95 | 0.18ms | 2.41ms | 13.4x faster | | Bundle Size | 281 KB | 634 KB | 56% smaller |

Throughput Under Load (50 concurrent connections, 30s): | Metric | rari | Next.js | Improvement | |--------|------|---------|-------------| | Requests/sec | 67,208 | 1,496 | 44.9x higher | | Avg Latency | 0.74ms | 33.44ms | 45.2x faster | | P95 Latency | 1.28ms | 41.89ms | 32.7x faster | | Errors | 0 | 0 | Stable |

Build Performance: | Metric | rari | Next.js | Improvement | |--------|------|---------|-------------| | Build Time | 1.35s | 3.75s | 2.8x faster | | Bundle Size | 281 KB | 634 KB | 56% smaller |

All benchmarks are reproducible. See benchmarks/ for methodology and scripts.

Contributing

We welcome contributions! Here's how you can help:

• Report Bugs - Found an issue? Open a bug report
• Suggest Features - Have ideas? Share your suggestions
• Improve Docs - Help make our documentation better
• Submit PRs - Check out our Contributing Guide

Community

• Discord - Join our community
• GitHub - Star the repo
• Documentation - rari.build/docs

Sponsors

rari is made possible by the support of these companies:

<div> <a href="https://get.neon.com/KDQudHN" target="_blank"> <img width="250px" alt="Neon - Serverless Postgres" src=".github/assets/neon.svg"> </a> </div>

Neon - Serverless Postgres. Autoscaling, branching, and scale to zero.

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Interested in sponsoring rari? Get in touch or support us on GitHub Sponsors.

License

MIT License - see LICENSE for details.