Rari – Rust-powered React framework • Hacker News Board

Re: Rari – Rust-powered React framework

#21

Post by skiniks » Thu, Feb 12, 2026, 8:41 PM UTC

laurencerowe wrote: post #14

skiniks wrote: post #11

Earlier quoted context omitted.

Not like ReasonML, you still write normal React/TypeScript. The Rust part is the server runtime. Instead of Node.js running your React Server Components, rari uses a Rust server with an embedded V8 engine. Same React code, different server underneath. You write React → Rust server executes it → better performance than Node-based alternatives.

How is this different than running that same React code in deno whose HTTP server is also written in Rust?

The main difference is that Deno doesn't have React Server Components support. You'd need to build the entire RSC runtime yourself (streaming, Suspense boundaries, server actions, etc.), whereas rari has this built in and optimized. rari also uses Axum for the HTTP layer with opinionated defaults for RSC workloads: streaming responses, proper cache headers, and optimized middleware are all configured out of the box.

While we use Deno's excellent crates (deno_core for V8 bindings, we're big fans of the project!), you're not locked into the Deno ecosystem. rari uses standard node_modules resolution, so your existing Node/npm workflows just work. Think of it like this: Deno gives you a runtime to build on, while rari gives you the full stack with integrated bundler, router, HMR, and dev server all configured to work together for RSC apps.

Re: Rari – Rust-powered React framework

#22

Post by mpeg » Thu, Feb 12, 2026, 8:42 PM UTC

ErenayDev wrote: post #19

mpeg wrote: post #15

Earlier quoted context omitted.

wait so it actually has a rust runtime? that's not documented in the site so I had assumed the rust part was simply rolldown it would be interesting to see a performance comparison to node and bun

I can only found this benchmarks https://github.com/rari-build/benchmarks

interesting, but would certainly be good to see an apples to apples benchmark of rari vs node/deno/bun for the same app, I would imagine the goals of the runtime are not to be a general runtime like those others, but it would still be good to see if it performs better

Re: Rari – Rust-powered React framework

#23

Post by rtcode_io » Thu, Feb 12, 2026, 8:52 PM UTC

[flagged]

Re: Rari – Rust-powered React framework

#24

Post by lionkor » Thu, Feb 12, 2026, 9:04 PM UTC

skiniks wrote: post #16

mpeg wrote: post #12

ok so I actually like this, but the description and documentation in general are terrible "rust-powered" meaning it uses rolldown to bundle the javascript, that's fine, but it's a weird thing to highlight, it's confusing for people that aren't super familiar with vite and might think this is a rust framework from the docs "one of rari's superpowers is seamless NPM package integration" this makes me think the docs are…

You're right about the messaging being confusing, I've been writing everything solo, so I'm definitely open to PRs that help with the copy. To clarify: "Rust-powered" refers to the server runtime itself, not just the bundler. The actual HTTP server, RSC renderer, and routing are all written in Rust (using an embedded V8 engine to execute your React components). It's not just Rolldown doing the bundling. On the npm in…

V8 is C++, so why isn't it "C++ powered"?

Re: Rari – Rust-powered React framework

#25

Post by sebringj » Thu, Feb 12, 2026, 9:05 PM UTC

this looks neat and reminds me of "Ferrari" for fast and combines "react" so it's a great name. Was there a specific use case for this that inspired you? I would imagine some massive existing heavy thing that you plugged in to fix to save it? I just put my open source thing out so it's nice to see some traction on yours, rooting for you.

Re: Rari – Rust-powered React framework

#26

Post by choiway » Thu, Feb 12, 2026, 9:05 PM UTC

Naming so lit

Re: Rari – Rust-powered React framework

#27

Post by zadikian » Thu, Feb 12, 2026, 9:08 PM UTC

dbacar wrote: post #13

"Rust-Powered Performance Native speed with Rust compilation for blazing-fast builds and runtime" It seems only Rust itself compiles slow while helping others brag about it :).

"I guide others to a treasure I cannot possess"

Re: Rari – Rust-powered React framework

#28

Post by koakuma-chan » Thu, Feb 12, 2026, 9:09 PM UTC

lionkor wrote: post #24

skiniks wrote: post #16

Earlier quoted context omitted.

You're right about the messaging being confusing, I've been writing everything solo, so I'm definitely open to PRs that help with the copy. To clarify: "Rust-powered" refers to the server runtime itself, not just the bundler. The actual HTTP server, RSC renderer, and routing are all written in Rust (using an embedded V8 engine to execute your React components). It's not just Rolldown doing the bundling. On the npm in…

V8 is C++, so why isn't it "C++ powered"?

They are using Deno

Re: Rari – Rust-powered React framework

#29

Post by skiniks » Thu, Feb 12, 2026, 9:18 PM UTC

splix wrote: post #18

skiniks wrote: post #4

Author here! Should be all good now, turns out the rate limiter was a bit overzealous

Nice project, thank you for working on it. I was trying to figure out the architecture, and I understand that it runs a Deno VM to execute JS on the backend? I was working on something similar, but for JVM backends [1]. And it seems there are a lot to learn from your project. For example, I'm using GraalVM that executes JS on the server. But I have to compile JS to WebAssembly because otherwise it produces a lot inte…

Thanks for checking it out! rari uses V8 (via deno_core bindings) embedded directly in the Rust runtime, not a full Deno VM. We execute JavaScript directly on V8 without compiling to WebAssembly.

The key is that deno_core provides clean Rust bindings to V8's C++ API, which lets us run JS/TypeScript with minimal overhead. We handle module resolution, imports, and the React rendering pipeline all in Rust, then execute the actual component code in V8. No WASM compilation step needed.

Your JVM project looks cool! The GraalVM → WASM approach makes sense for JVM integration. We avoid those integration issues by keeping everything in the Rust/V8 ecosystem. The tradeoff is we're tied to V8, but we get native performance and direct access to V8's features.

Re: Rari – Rust-powered React framework

#30

Post by skiniks » Thu, Feb 12, 2026, 9:22 PM UTC

lionkor wrote: post #24

skiniks wrote: post #16

Earlier quoted context omitted.

You're right about the messaging being confusing, I've been writing everything solo, so I'm definitely open to PRs that help with the copy. To clarify: "Rust-powered" refers to the server runtime itself, not just the bundler. The actual HTTP server, RSC renderer, and routing are all written in Rust (using an embedded V8 engine to execute your React components). It's not just Rolldown doing the bundling. On the npm in…

V8 is C++, so why isn't it "C++ powered"?

Technically you could say that, but the entire server runtime is written in Rust. V8 is just the embedded JavaScript engine. By that logic, every Node.js or Deno app would be "C++ powered" since they all use V8.