Hackers' Pub

Syntax	Description	Examples
`"` keyword `"`	Finds the string within quotes, including spaces. Case-insensitive. (Escape quotes inside with `\"`)	`"Hackers' Pub"`
`from:` handle	Finds content written by the specified user.	`from:hongminhee` `from:hongminhee@hollo.social`
`lang:` ISO 639-1	Finds content written in the specified language.	`lang:en`
`#` tag	Finds content with the specified tag. Case-insensitive.	`#HackersPub`
condition condition	Finds content that satisfies both conditions on either side of the space (logical AND).	`"Hackers' Pub" lang:en`
condition `OR` condition	Finds content that satisfies at least one of the conditions on either side of the OR operator (logical OR).	`#HackersPub OR "Hackers' Pub" lang:en`
`(` condition `)`	Combines the operators within the parentheses first.	`(#HackersPub OR "Hackers' Pub" OR "Hackers Pub") lang:en`

Patrick Dubroy @dubroy@hachyderm.io

9/30/2025, 7:08:39 AM

Public

Whoah. TIL that yt-dlp (the command line video download tool) includes a crude JS "interpreter" (~1k lines of Python).

https://github.com/yt-dlp/yt-dlp/issues/14404#issuecomment-3330980464

via @cfallinChris Fallin

Why can't yt-dlp's native JavaScript interpreter be improved to handle the new YouTube player JS?
Currently, yt-dlp relies on a complicated set of regex patterns to identify the necessary functions in the YouTube player JS, and relies on even more regex to try and interpret that JavaScript code natively within Python.

This code was already hugely costly to maintain. Any time YouTube changed something about their player JS, it would cause multiple maintainers to drop everything and spend all of their free time for the next 2-3 days trying to fix things.

With the latest changes, the necessary functions are spread out all over the player and are much more difficult to identify. Continuing to use the regex-based approach would be far too brittle and far too costly (i.e. maintainers would be spending all of their free time for the next 2-3 weeks after a breakage trying to fix things).

So the regex-based approach has been abandoned in favor of an AST-based approach (https://github.com/yt-dlp/ejs), which should allow us to respond much more quickly to changes in the player JS, even as its obfuscation increases.

Python code from yt-dlp's YouTube extractor showing a function that extracts and processes JavaScript function names, with regex pattern matching and debugging output

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