Turns out "its just an experiment, you all are overreacting" was just a lie to damp criticism.

https://news.ycombinator.com/item?id=48019226

Merging a complete rewrite in another language in 9 days seems insane to me. Maybe I'm just too cautious but with something like this I'd split off as a separate binary and get some heavy use customers involved as testers first to see if it causes any unforeseen problems before slowly expanding it out.

I'd want to be pretty damn confident it won't cause any regressions before sunsetting the original codebase in favor of this one.

	▲	goyozi 2 hours ago \| parent \| next [-]
		I don’t think you’re too cautious. Big upgrades and rewrites is somewhat of a „work hobby” of mine and this seems waaay too fast. I don’t know how the Bun canary process works and I guess their test suite is better than typical projects but still… I can’t imagine this working out well without testing it on a variety of big projects for a significant amount of time. There’s probably loads(?) of observable behaviors that people rely on, consciously or not. Even _if_ the new thing is 100% spec compliant, it might still be breaking or otherwise problematic for heavy users. That said, I’d love to be proven wrong. I use Bun from time to time on small stuff and I enjoy it, so I wish them well (:
	▲	progbits 2 hours ago \| parent \| prev [-]
		> too cautious No, you are perfectly normal. The people who in one week decided to replace the whole codebase for a widely used tool with code no human has seen are the crazy ones.

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franciscop 2 hours ago | parent | prev | next [-]

It seems it was an experiment at that moment, and that it went well? I do hope they release it under 2.x though, cannot imagine how a 1M LoC can break in so many ways, especially if what xiphias says is true:

https://news.ycombinator.com/item?id=48132902

	▲	camel-cdr a minute ago \| parent \| next [-]
		If I got magically handed the perfect rust rewrite for a project of this magnitude, it would take way longer than 9 days to merge, because I would need to make sure it's actually good.
	▲	latexr 2 hours ago \| parent \| prev [-]
		> It seems it was an experiment at that moment, and that it went well? There’s no way they can know that for sure. A change of this magnitude cannot go from experiment to success in such a short time frame. Even if all the code were 100% correct, you can’t call it a success until it’s battle tested in real world scenarios for a while, and that is impossible without time. Same way you can’t cook properly by throwing food into a vulcano. It’s not just about the temperature. Either the “experiment” claim was a lie or they are being irresponsible.

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randypewick 2 hours ago | parent | prev | next [-]

The experiment might have turned out well, or the author might have spent enough time to bring it to a place they was comfortable.

Frustration moves mountains, I don't think this rewrite was done lightly.

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keyle 2 hours ago | parent | prev | next [-]

I'm no believer... 9 days later... Lessssssgoooooooo wooooooooo <sunglasses and rave>

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mapcars 2 hours ago | parent | prev | next [-]

Well it was 9 days ago, at the time they were not confident, but maybe the results were insanely good.

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tclancy an hour ago | parent | prev | next [-]

> was just a lie to damp criticism.

Citation needed. Couldn't it just as easily have been one person being as suspicious of the task as everyone else seemed to be?

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impulser_ 3 hours ago | parent | prev [-]

"We haven’t committed to rewriting. There’s a very high chance all this code gets thrown out completely."

	▲	jen20 2 hours ago \| parent [-]
		People conflate “high chance of X” with “X will happen” all the time. See elections, for example.