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Comment by arm32 | Hacker News Reader

Ah, yes, the classic "Playwright isn't fast enough so we're reinventing Puppeteer" trope. I'd be lying if I haven't seen this done a few times already.

Now that I got my snarky remark out of the way:

Puppeteer uses CDP under the hood. Just use Puppeteer.

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I've seen a team implement Go workers that would download the HTML from a target, then download some of the referenced JavaScript files, then run these JavaScript files in an embedded JavaScript engine so that they could consume less resources to get the specific things that they needed without using a full browser. It's like a browser homunculus! Of course, each new site would require custom code. This was for quant stuff. Quite cool!

This exact homunculus is actually supported in Node.JS by the `jsdom` library: https://www.npmjs.com/package/jsdom

I don't know how well it would work for that use-case, but I've used it before, for example, to write a web-crawler that could handle client-side rendering.

our use primary use-case with the AI stuff is not really scraping, we're mostly going after RPA

Is the case for playwright over puppeteer just in it's crossbrowser support?

We're currently using Cypress for some automated testing on a recent project and its extremely brittle. Considering moving to playwright or puppeteer but not sure if that will fix the brittleness.

In my experience Playwright provided a much more stable or reliable experience with multiple browser support and asynchronous operations (which is the entire point) over Puppeteer. ymmv

Playwright also offers nice sugar like HTML test reports and trace viewing.

From my experience with Playwright RR-Web recordings are MUCH better than Playwright’s replay traces, so we usually just use those.

What's RR web?

https://github.com/rrweb-io/rrweb

That can be integrated with Playwright, or did you mean to say it is already used under the hood for their reports?

Gregor was saying it works without needing playwright, and provides more detailed trace recordings than playwright does.

we plan to use rr-web and maybe browsertrix for our website archival / replay system for deterministic evals.

I would definitely recommend puppeteer if you can, it's maintained by the Chrome team and always does things the "approved way". The only reason we did playwright is because we're a python library and pyppeteer was abandoned.

Most of the Puppeteer team left and joined Playwright under Microsoft.

While that is the origin story of Playwright in 2020, that's no longer really true. Puppeteer is alive and well and arguably moving faster than Playwright these days because it's updated in lockstep with https://github.com/ChromeDevTools/devtools-frontend

Also recently found it unnecessarily difficult to do profiling of page workers using Playwright's CDPSession wrapper (and they don't seem to have any plans to improve it: https://github.com/microsoft/playwright/issues/22992#issueco...), whereas it was pretty painless in Puppeteer.

So, definitely more useful if you care about more than just your main thread.

I have converted several large E2E test suites from Cypress to Playwright, and I can vouch that it is the better option. Cypress seems to work well at first, but it is extremely legacy heavy, its API is convoluted and unintuitive, and stacks a bunch of libraries/frameworks together. In comparison, Playwright's API is much more intuitive, yes you must 'await' a lot, but it is a lot easier to handle side effects (e.g. making API calls), it can all just be promises.

It is also just really easy to write a performant test suite with Playwright, it is easy to parallelize, which is terrible in Cypress, almost intentionally so to sell their cloud products, which you do not need. The way Playwright works just feels more intuitive and stable to me.

They're all brittle in my experience but Playwright has a lovely test recorder and test runner which is also integrated into VSCode, and it tidies up a lot of the exceptions that would occur in puppeteer if the page state wasn't meticulously-ready for some operation.

Playwright's "trace" viewer is also fantastic providing periodic snapshots and performance debugging.

sir we are a python library, puppeteer-python was abandoned, how exactly do you propose we use puppeteer?

Playwright has Python bindings .

yes I know, I wrote the post

Have you considered just using Playwright? ;)

yeah, i continue to be amazed at how google dropped the ball on this one.

Wait, does playwright not use cdp? What does it do?!

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