I think your final comment gets at it. If they said "OK, I am skeptical, so we're going to pause on updating to see how this Rust thing plays out" -- that sounds like a reasonable engineering decision. Saying "because they vibe coded we are dropping support for Bun" sounds political.
I don't think "political" is necessarily a bad thing. Engaging in politics is how you shape the world. The mere act of writing and maintaining yt-dlp is quite political considering the context of IP law and enforcement that we live in.
It happens that in this case that I'd disagree with their politics if that's why they are dropping Bun support - I think there's a great deal of value in moving to memory safe languages, little harm in accepting anthropic compute and funding to do so, and that use LLMs themselves is roughly value neutral (though many uses are very much not value neutral). That said reasonable people definitely disagree with me.
EDIT:
Everyone is rightfully calling me out that this doesn't make a lot of sense. What I meant is that the move is driven by ideology. I think there is a lot of overlap between politics and ideology, and an increasing amount of overlap between ideology and emotion. But it's fair enough to call me out here.
I'm not familiar with this definition in any modern or archaic sense. Is there somewhere I can read about it? Just because a decision is not directly engineering related (which I'm not even convinced this is) doesn't mean that it's not thoughtful.
- free and open source, which is an ideology, and that
- expands access to otherwise locked down media, which is again an ideological stance
Regardless, the decision was 99% logical. In fact, even the emotional parts are laudable. For example, I love software. That's an emotion. If you disagree with that foundation, we will fundamentally never be able to converse with each other about what's best for software.
> I've felt this way for a long time, but for the past month I've kept a journal where I put an "X" next to every date where a GitHub outage has negatively impacted my ability to work2. Almost every day has an X. On the day I am writing this post, I've been unable to do any PR review for ~2 hours because there is a GitHub Actions outage3. This is no longer a place for serious work if it just blocks you out for hours per day, every day.
That isn't ideological in the slightest. Count the X's, and move off once you see too many.
Were Bun's tests generated by an LLM? If they were, were they read by a human afterwards to be validated?
[1] https://kant2002.github.io/en/llm/2026/05/16/bun-pr-analysis...
Neither of these can be replaced by an automated test suite of any kind, and all of these are examples of good engineering practices that guarantee software quality.
Additionally, even if you don't (need to) adhere to the best engineering practices and instead rely solely on an automated test suite, the tests in this suite must be validated - read and understood - by a human in order to guarantee that they nail down the correct requirements.
I think it's fair to call me out for skipping a step, but I wasn't using it to mean "idea I don't agree with".
I believe, maliciously or innocently, you were.
What is politics without ideology?
Fear (emotion) is used (advantageously) to force us to check that something isn't going to break us
In this instance fear is being used to ensure that yt-dlp is not exposed to (genuine) concerns about the quality of bun that is openly being built making use of tools we as a whole know is problematic.
I agree with you that the statements are a bit over the top (that's an emotional response to their statements btw) and that (eventually) you would /hope/ that bun gets to a point where it's got some genuine reliability from a users perspective.
Edit: I see your edit to explain that the issue is ideology - but unfortunately (perhaps) that's not an improved stance - ideology has to guide us when we just don't know - it's a heuristic.
OpenAI itself is a bundle of ideologies and pretend ideologies. Thw whole puah for AI and AIG is way more about emotions and ideology then about business ir engineering.
this amounts to "i don't trust this dependency anymore, so i'm cutting it out for my own good"
that's fine
Stopping maintaining and testing support for upcoming versions is cheaper than doing that work.
Sure it’s political but it is also just a sane approach, to stay away from such disruptive change and treat it as wait-and-see instead of tagging along for the ride. There is not really any technical upside to tagging along and promising support.
If it’s based on predictions of how some alpha software might turn out in the future then I don’t see how you can claim it’s cheaper.
If a bunch of new bug reports came in then you said no, then everyone would understand.
This is pretty obviously ideological otherwise. Which is fine, but we shouldn’t pretend otherwise because we might agree with it
That would still be rational if it had been rewritten by hand, and not by an LLM.
Here was the Bun team's message on merge:
> It passes Bun's pre-existing test suite on all platforms (and fixes several memory leaks and flaky tests), the binary size shrinks by 3 MB - 8 MB, the benchmarks are between neutral and faster - and most importantly, we now have compiler-assisted tools for catching & preventing memory bugs, which have costed the team an enormous amount of development & debugging time over the years.
>
> The codebase is otherwise largely the same. The same architecture, the same data structures. Bun still uses few 3rd party libraries. No async rust.
It's unfortunate that this is what some call "engineering" while labeling actual science and engineering as "politics."
yt-dlp is under no obligation to keep using a dependency from vendors that instantly flip flop and re-frame their own words and actions. That's what actual due diligence and responsible engineering looks like.
Something that's experimental can receive further changes and then no longer be considered experimental.
I already have, as have others, but
> It sounds like you think they've made a stable release already?
What's the point if you keep refusing to acknowledge the issue and tossing out theories about how I and others might be wrong, just to see what sticks?
> None of the new code is sent to users yet.
So? The decision to adopt was already made and the code was merged without planning, without considering downstream impacts, and without proper inspection. People who won't read their own code before merging won't read it after. But many of you don't even see this as an issue. So again, what's the point in trying to point all of this out?
Also you yourself said the experiment is over. You can't have it both ways.
> It's a direct translation without relying on major AI decisions.
Because the genie said so? That sounds lacking in scientific rigor, but
> I'm happy to call them cowboys if they make a release with lousy testing.
Oh right, that the test passes is proof that the new code is debuggable, maintainable, architecturally sound, semantically equivalent to the old code, and non-disruptive for downstream users. Apparently testing has leapt centuries ahead in the past two weeks or so.
The translation did not change the architecture: it was a 1:1 translation with even the same internal data structures. Rust written in a zig-like way, with the original Zig still available as reference. AI can make an absolute mess when making architectural decisions, but translation like this plays to the strength of current AI, especially when moving to a stricter language.
The code being in the dev branch means that they now are open to community feedback and testing, and no date is set on it being declared stable. We'll see how the team handles it.
It is by definition cheaper to not support extra runtimes like Kaluma, Elsa, WinterJS. Adding support is not just the initial work of adapting CI and writing policies, maintenance and support is ongoing work.
AI includes a lot of technologies, LLMs being just one of them. Several of these technologies use probabilistic algorithms, so having randomness does not disqualify something from being classified as AI.
They also have the worst possible failure mode imaginable: Producing erroneous output that looks perfectly fine and expertly-crafted.
Imagine a food synthesizer machine. You press a button. 80% of the time you get a chicken sandwich, 20% of the time it beeps an error. That's OK. With the LLM version of that, 80% of the time you get a sandwich, 20% of the time you get what looks like a perfect sandwich except that it contains bits of plastic and metal, and you have to start eating it to find the pieces.
"You're absolutely right! Food shouldn't contain bits of plastic. Let me synthesize that again."
If they had decided to drop Bun for "AI assisted coding," that might strike me as a political decision.
I disagree that this is a political stance. People based on their experiences have formed opinions on whether they trust that model of development or not. Bun having taking extreme measure of going 100% in within a week is itself extreme positioning from their side which will likely result in extreme reactions because depending on who you are and your experience you'd bet on the fact that it may or may not work out.
This is actually fascinating. How does my opinion matter? Should I join all the socials (this is my only form of social media) and stand on my soapbox and shout into the void? Do I need to express I care so others know I care and have picked a side and have opionions on evrything?
I do not care. My opinion does not matter. I can scream into all the voids. I can virtue signal until the heat death of the universe/until I die, it matters not. I don't have the desire to spend the limited emotional bandwidth on giving a flaming fuck about the world around me. I'm not that arrogant or self-centered to think anyone else cares.
“Learned helplessness” himself graced us with his presence.
That feels like an entirely reasonable stance to take.
And I see the argument/correction downthread that it's an "emotional" or "ideological" stance. Why does it have to be that? It seems completely rational and logical not to trust software written by a technology that is known to hallucinate and "cheat" to make tests pass.
Of course, I can't say that the yt-dlp maintainer is or isn't being political/emotional/ideological when making this decision; none of us can know their true motivations without asking them, and I choose the charitable explanation unless shown evidence otherwise.
I get the idea to "battle-test" the rewrite first but (a) how does one even determine a reasonable timeframe for battle-testing that much LOC and (b) each vibe-coded update pushed to the Bun upstream basically resets the battle-testing timer. I guess you could lag behind $LATEST by a given window but that just brings us back to (a).
The other side of this is that as far as I'm aware, Bun support in yt-dlp was always experimental. They mainly use Deno.
On the flip side it's not on the yt-dlp authors to test Bun's new development process and see if it results in more segfaults, OOMs, security vulnerabilities, etc. In fact it would arguably be negligent to experiment on your users if you thought there was a reasonable probability of increased security vulnerabilities.
I think there's a good argument that the responsible thing to say would be "we aren't going to immediately support running our software on a new bun release cut from main right now".
It seems a bit unfortunate to me that they've apparently already intending to never support future releases instead of planning on re-evaluating in the future. On the other hand the yt-dlp developers definitely don't owe anyone anything.