I have not used it in production yet, but it's been great for one-off scripts and side projects. Setting up a TypeScript Node environment with ts-node, ts-jest, ESM support, top level await, etc. is more annoying than it should be. More recent Node releases have alleviated some of this pain, but not as trivial as running bun init.
Ohh bun shell looks interesting. I was looking at zx[1] for some frontend pipeline scripting tasks that were just beyond maintainable bash, but maybe I'll give bun shell a go.
It’s good unless you want a repl (they pretend to have one but it’s miserable: >6s latency all the time when it updates), or you plan to use any native modules. The error messages are also significantly worse than node’s. I used it for a bit, but node with ‘—loader tsx’ does everything I want nowadays with none of the downside. If I was building a simple server, perhaps with websockets, and I was sure it need native modules, I’d consider using Bun. I have several such services live now actually.
I too would use it if the REPL worked properly. JS developers are often used to working interactively - the browser/console workflow - and have come to rely on testing ideas or problems / solutions in the REPL interactively.
It's efficient, as you can test and narrow things down in isolation and figure out what is working or not-working very quickly. It's also a good way to try a new module, and this is reflected in docs that eg, use node's REPL as a demo.
One bizarre problem with bun's REPL at the moment, which can be quite the unexpected "gotcha", is the REPL itself seems to be cached, and it goes stale. It actually expects to be able to update itself online every day or so, or it breaks!
Yeah, well cool - unless you ever work offline. Eg, had you expected to work on a long flight and now half your dev workflow was broken, for no good reason. (And unfortunately bun's "--prefer-offline" flag had no effect.)
I don't want to criticise bun too much - it is incredibly fast, and has made other significant workflow enhancements.
But a REPL is a dealbreaker for some of us. I guess it's similar to hot code-reloading in compiled languages, you don't go back to the minutes-long compile-wait cycle for the kinds of problems that kind of workflow makes instantaneous.
Currently, the REPL is an alias of `bunx bun-repl`, and bun-repl is a community-maintained npm package. We haven't had the time to do our own REPL. Honestly, we really need to hire more engineers. We're a small team and there's so much to do
Yes, Bun uses uWebSocket internally. I think OP was saying the perf gain comes from the combination of Bun + uWebSocket. For http, most of that is coming from uWS, which is pretty much best performing HTTP framework out there ime.
Been using it recently and it’s great, the quality of life stuff is really nice (like, not having to worry about compiling TS) and it’s really fast. Some things are still missing though, but for me it’s already better than Node
It has been extremely fun to use for personal projects. There are still some things that just do not work, though, like brotli compression which means any library using axios with their default brotli compression setting will crash at runtime. There is also no equivalent to the `npm outdated` command and a few other niceties. It is always little unexpected things, so it would be difficult to recommend for production uses just yet, but things are improving rapidly and I could see it becoming stable enough very soon. The APIs it exposes are so awesome—like giving node an excellent standard library—and the fact that I don’t need a compile step to execute TypeScript code makes it easier to get up and running with Bun than without it. Highly recommend trying for non-production work!
oh yeah, it's amazing! The speed is great but just the DX is so much nicer than npm, yarn, or node itself. It took us a few tries to getting it working for our prod environments, but nothing we couldn't figure out within the same day.
I thought having a binary for a lock file was weird (don't know the technical reasons behind it besides maybe speed) but after using it for months now, it never has caused an issue for us.
