2 votes

Wilson Lin on FastRender: a browser built by thousands of parallel agents

4 comments

  1. [3]
    danke
    Link
    As mentioned in the HN comments, what "from-scratch" (per the CEO) means here is that it actually uses the following dependencies: Servo's HTML parser Servo's CSS parser QuickJS for JS selectors...

    As mentioned in the HN comments, what "from-scratch" (per the CEO) means here is that it actually uses the following dependencies:

    • Servo's HTML parser
    • Servo's CSS parser
    • QuickJS for JS
    • selectors for CSS selector matching
    • resvg for SVG rendering
    • egui, wgpu (v0.17, from June 2023), and tiny-skia for rendering
    • tungstenite for WebSocket support

    So it's "just" Servo plagiarized, deconstructed and then made significantly worse.

    8 votes
    1. redwall_hp
      Link Parent
      AI code in a nutshell. It's copyright laundering.

      AI code in a nutshell. It's copyright laundering.

      3 votes
    2. skybrian
      Link Parent
      It’s using some powerful building blocks, but does have to draw the rest of the owl.

      It’s using some powerful building blocks, but does have to draw the rest of the owl.

  2. skybrian
    Link
    From the article: [...] [...] [...] [...] [...] [...]

    From the article:

    Last week Cursor published Scaling long-running autonomous coding, an article describing their research efforts into coordinating large numbers of autonomous coding agents. One of the projects mentioned in the article was FastRender, a web browser they built from scratch using their agent swarms. I wanted to learn more so I asked Wilson Lin, the engineer behind FastRender, if we could record a conversation about the project. That 47 minute video is now available on YouTube. I’ve included some of the highlights below.

    [...]

    Wilson started what become FastRender as a personal side-project to explore the capabilities of the latest generation of frontier models—Claude Opus 4.5, GPT-5.1, and GPT-5.2. 00:56

    [...]

    A browser rendering engine was the ideal choice for this, because it’s both extremely ambitious and complex but also well specified. And you can visually see how well it’s working! 01:57

    [...]

    Once it became clear that this was an opportunity to try multiple agents working together it graduated to an official Cursor research project, and available resources were amplified.

    [...]

    The great thing about a browser is that it has such a large scope that it can keep serving experiments in this space for many years to come. JavaScript, then WebAssembly, then WebGPU... it could take many years to run out of new challenges for the agents to tackle.

    [...]

    We talked about the Cargo.toml dependencies that the project had accumulated, almost all of which had been selected by the agents themselves.

    Some of these, like Skia for 2D graphics rendering or HarfBuzz for text shaping, were obvious choices. Others such as Taffy felt like they might go against the from-scratch goals of the project, since that library implements CSS flexbox and grid layout algorithms directly. This was not an intended outcome. 27:53

    [...]

    The thing I find most interesting about FastRender is how it demonstrates the extreme edge of what a single engineer can achieve in early 2026 with the assistance of a swarm of agents.

    FastRender may not be a production-ready browser, but it represents over a million lines of Rust code, written in a few weeks, that can already render real web pages to a usable degree.