Show HN: Lightpanda, an open-source headless browser in Zig

How does this work because the browser needs to render a page and the vision model needs to know where a button is, so it still needs to see an image. How does headless make it easier?

Headless mode skips the visual rendering meant for humans, but the DOM structure and layout still exist, allowing the model to parse elements programmatically (e.g. button locations). Instead of 'seeing' an image, the model interacts with the page's underlying structure, which is faster and more efficient. Our browser removes the rendering engine as well, so it won't handle 100% of automation use cases, but it's also what allows us to be faster and lighter than Chrome in headless mode.

But what if the human programmer needs to visually verify that their code works by eyeballing which element got selected, etc?

You're right, the debugging part is a good use case for graphical rendering in a headless environment.

I see it as a build time/runtime question. At build (dev) time I want to have a graphical response (debugging, computer vision, etc.). And then, when the script is ready, I can use Lightpanda at runtime as a lightweight alternative.

If you want a human to eyeball it, you don't use a "headless" browser.

The human programmer can save the DOM as HTML in a file and open it in a headfull browser.

But the use case for Lightpanda is for machine agents, not humans.

The issue is that DOM structure does not correspond one-to-one with perceived structure. I could render things in the DOM that aren't visible to people (e.g. a transparent 5px x 5px button), or render things to people that aren't visible in the DOM (e.g. Facebook's DOM obfuscation shenanigans to evade ad-blocking, or rendering custom text to a WebGL canvas). Sure, most websites don't go that far, but most websites also aren't valuable targets for automated crawling/scraping. These kinds of disparities will be exploited to detect and block automated agents if browser automation becomes sufficiently popular, and then we're back to needing to render the whole browser and operate on the rendered image to keep ahead of the arms race.

I was doing a personal side project for a while where I was trying to make my own little Wayback Machine-alike. Mine was very rudimentary, built on top of Firefox and WebDriver plus Squid proxy.

For debugging purposes you could have your headless browser function as a HTTP Proxy Server, maybe? And in your headless browser you could capture a static snapshot of the DOM after your JavaScript runtime has executed the scripts for the page. Similar to how the archive.today guy serves static snapshots of websites. And then developers using your headless browser could point their Firefox or Chrome browser to the HTTP Proxy server hosted by your headless browser program, in order to get a static snapshot view of what the DOM is like after your headless browser has executed JavaScript from the page. And then Firefox or Chrome will render static HTML view of what the page looked like to your headless browser, that the developer can inspect to make decisions about further interactions with the page. As a tool for debugging.

Servers operate on top of tcp/ip not to serve information, rather to serve information plus something else, usually ads. This is usually implemented with websites and captchas n stuff.

That's a problem of misaligned economic incentives. If there is a blockchain which enables micro-transactions of 0.000001 cent per request, and in the order of a million tps or a billion tps, then servers have no reason not to accept money in exchange for information, instead of using ads to extract some eyeball attention.

There is no reason that i cannot invoke a command line program: `$fetch_social_media_posts -n 1000` and get the last thousand posts right there in the console, as long as i provide some valid transactions to the server.

Websites and ads are the wrong solution to the problem of gaining something while serving information, and headless browsers and scraping are the wrong solution to the first wrong solution and the problems it creates.

No need for blockchain, microtransaction functionality should be integrated into our existing payment methods.

Existing payment methods, paypal, google pay etc, have been absolutely crucial for internet payments, but the micro in the word never ends.

If there are internet payments with a minimum payment of 1 cent, then we need payments of 0.1 cents. If that's achieved, then we need 0.01 cents minimum transaction. The micro in the transaction always needs to be smaller (and faster).

Free competition (or perfect competition) over a well defined landscape, internet protocols that is, has proven to always deliver better quality goods and lower price. Money derived from governments is far, far from free competition, let alone well defined internet protocols, and there is a point in which existing payment methods get stuck and cannot deliver smaller transactions.

I don't personally know where and when that point is, but if i have to guess, existing payment methods have reached that minimum point for at least a decade. In other words, their transactions minimums have to be high enough for them to make a profit. Yes, they can implement microtransactions, but they will not be profitable.