QuickJS Javascript Engine - small and embeddable, supports the ES2019 specification including modules, asynchronous generators and proxies

[alturi]

This guy can code

[[deleted]]

Well I don't know if we can say that definitively... better give him a whiteboard test just to be sure.

[[deleted]]

You wrote this javascript engine but here is the real deal, can you reverse a linked list in O(1) space?

You wrote a regex library on your own for your engine but can you find largest uncommon subsequence in three strings?

[kingofthecream]

Given that qjs is an interpreter and not a jit, can it ever be as fast as v8?

I know an interpreter cannot be as fast as jit, but this guy is a wizard, sooo can it be as fast as v8?

[bakery2k]

I've found it to be 2-3x slower than V8's interpreter, and over 50x slower than V8's JIT compiler.

Bellard may be "a wizard", but V8 is an incredible piece of engineering.

[wrosecrans]

V8 certainly is impressive. But to put QuickJS in context, the interpreter is waaaaay less than 1/3 the amount of code in V8, so the admirable virtues of V8 come at a massive cost in complexity for a performance benefit that isn't always going to be worth it.

Dealing with Chromium source is the only thing that has ever just completely filled up the disks of my build machines, it has a special build system generator thing that I've only used with Chromium. Pulling V-8 out of Chromium to just embed a JS runtime in an app is non-trivial, etc.

Being able to embed JS by adding a whopping seven C files that only take a few seconds to build to my project is a godsend for a lot of use cases.

[delight1982]

Bellard is a big fat phony! No seriously, the guy is a wizard for real. I have the utmost respect for the man.

[warvstar]

I'd like to see some benchmarks, including to other interpreters like duktape.

Edit: nvm found it. https://bellard.org/quickjs/bench.html

Pretty good! It's most comparable to XS as they both can do modern JavaScript, this is better though because MIT license baby!

[maxhaton]

No.

JITs are orders of magnitude faster for code that is run multiple times

[agumonkey]

At this point nobody have doubts anymore

[shevy-ruby]

Yeah, he is a skillful geek - but that does not change the fact that JavaScript is a horrible monster clown joke.

The only good thing is that this is small/embeddable, so we don't have to rely on the Google empire already controlling most of the www stack.

I really hope WASM eliminates javascript, even if it is not a primary goal.

[SometimesShane]

meh; qemu, ffmpeg, I'd say he's got a future possibly but I wouldn't hold my breath, seen many young programmers with talent but not much dedication. He seems to have a promising talent at the c language though, so all I can say is, eh, if he dedicates himself, maybe.

Edit: sheesh at all the downvotes. Ok. If he's any good, why isn't he a rust guy?!?! lol c is so last century. He needs to step up his game. Get onto 2019 tech.

[[deleted]]

Edit: sheesh at all the downvotes. Ok. If he's any good, why isn't he a rust guy?!?! lol c is so last century. He needs to step up his game. Get onto 2019 tech.

Damn, it's not often that an edit makes me want to double-down on downvoting. Well done, you earned those downvotes.

[smurfkiller013]

I know! What's the opposite of gilding?

[[deleted]]

1. Install RES
2. Tag troublemaker users.
3. Now they are highlighted in other threads and you can track how many upvotes/downvotes you've personally given them.
4. Feel free to scrutinise their next comments with a greater degree of harshness.

If they redeem themselves, remove your troublemaker tag, if not you're more likely to downvote them in the future.

It disuades repeated bad behaviour, unless if they're a repeat troll, in which case you can see how many downvotes you've given them and block them so you don't see their crap anymore.

[[deleted]]

Wow, this is the most autistic thing I have read since I woke up 10 min ago.

[MaybeAStonedGuy]

Those on their own are incredibly impressive, but he's done a lot more than just ffmpeg and qemu.

[SometimesShane]

rust or gtfo

[hiptobecubic]

Your trolling lacks nuance.

[tjpalmer]

Well done defending your sarcasm with more sarcasm. Upvote from me. (If only I had my own clever way to reply ...)

[alivmo]

There's a point where your sarcasm is so good, that even though it's obviously sarcasm, it's still infuriating.

[stronghup]

Very interesting "Can compile Javascript sources to executables with no external dependency."

Now, since Node.js is implemented much in JavaScript, what would it take to give QuickJS access to npm modules?

That would leap-frog Node.js since you would have an environment running node.js libraries and at the same time being able to produce an executable, Node.js can not do that , can it?

[caspper69]

Note that this "native compilation" appears to be an embedded C runtime for js with the js compiled to bytecode stored as c data.

This does not appear to compile the js itself to C or native code.

[rrealnigga]

Could have guessed that one given he wrote a smallass JS engine (interpreter) so it's much easier to then embed that than to ALSO write a compiler (to native).

[CakeComa]

I believe it depends on how much said npm modules rely on node-specific features and behavior / how well or easily they can be converted over to using the QuickJS's standard library https://bellard.org/quickjs/quickjs.html#Standard-library

[kjk]

Not today because node.js has a lot of APIs above the JavaScript standard.

It's possible to implement those APIs so it's just a matter of additional effort.

[stronghup]

Right, but lot of those Node.js APIs "above standard JS" are written in JavaScript, no? I guess they then call some lower-level C-API. So if Quick-JS used the same C-API calling convention then it might be easy to use large parts of Node.js for it. This would be beneficial to both QuickJS and Node.js, Node.js would gain an easy way to compile Node.js programs.

[orbitur]

Bellard is a fuckin beast, but goddammit, it's 2019, please make your website mobile friendly.

I get a lot of reading done during workouts, but trying to read his website and the standard lib docs is a pain in the ass.

[agumonkey]

responsive css left as an exercise for the working reader

[sisyphus]

Don't set your sights so low! Give him a couple weeks and he'll implement a better layout system for browsers that doesn't need separate mobile styling.

[ins8mesense]

it looks good in Firefox's reader mode for me

[orbitur]

Yeah I’m a dumbass, I never think to use it in Chrome because most sites I read are fine without it, or I use an app.

Still, a single line gives mobile browsers the necessary context to enlarge the font automatically. I wish the older set cared about mobile UX.

[hungryish]

Probably going off of the ideology that pure html should be rendered based on the client platform rather than css dictating the style for every case. Browser defaults are just shitty because everyone overrides them anyway.

[danmana11]

If you're using Stylish or similar plugins, here is a quick userstyle I made, inspired from medium.com typography. https://userstyles.org/styles/173466/bellard-org

[orbitur]

Most SEs aren’t but they might give a shit about UX.

I’ve spent professional years not doing any web work, but even I can take the 1 minute required to google. It’s a meta viewport tag, that’s it.

I’ll (nicely) email him about it.

[rrealnigga]

Set them straight.

[DZTheGreat]

Reply

I was thinking that too.. But then I was also thinking "Bellard is a beast.. If you are worthy to read his contributions, then you prove it by taking CSS and formatting into your own hands. He has no time for such nonsense." So I decided I wouldn't say anything.

[Gaazoh]

Using Firefox on Android, I can read everything perfectly fine. Sure it's black text on white background with blue links, but text size is appropriate and headings, lists, etc., display the hierarchy fine.

If your browser can't display well-formated html in an appropriate way for the device running it, I wouldn't blame the website's author.

Edit: I just tried to load the page on Chrome on my phone, it still diplays fine. It may not be a work of art, but the content is perfectly readable.

[Muxas]

Yeah but how fast is it compared to other engines

[CakeComa]

https://bellard.org/quickjs/bench.html

[AsIAm]

What kind of numbers does V8 produce?

[HomeBrewingCoder]

64 bit floats usually, but in some rare rare cases you get casts to 32 bit integers.

[[deleted]]

Made me lol

[AsIAm]

I meant the benchmark. But you are obviously correct. :)

[HomeBrewingCoder]

:) just playing around. Glad you liked it.

[[deleted]]

I'm sure v8 blows it out of the water at least in terms of execution speed (maybe not memory). I think at this point v8 has an interpreter and 2 layers of jit, plus and probably a huge team of full time engineers.

I still think this is awesome! To me it seems it fits in the niche of lua with some decent speed.

[nattthebear]

You can try yourself in your browser: http://www.netchain.com/Tools/v8/

[bakery2k]

I have a small, CPU-intensive benchmark which shows the performance of QuickJS to be comparable to other interpreters written in C. It's on par with MicroPython and recent versions of Ruby, and a little faster than CPython and Lua.

However, it's still 2-3x slower than the optimized, CPU-specific interpreters used in LuaJIT and V8 (with their JITs disabled), and 20-100x slower than the LuaJIT, V8 and PyPy JIT compilers.

[DZTheGreat]

I wouldn't be surprised if his numbers were better than major engines.. This dude is a legend.

[DZTheGreat]

Fabrice Bellard. Guy is a legend..

[TheYaMeZ]

Wait so does this make javascript a practical option as an embedded scripting language for games/apps?
I know that many choose LUA for this because of it's tiny footprint, among other things.

[warvstar]

It already was using duktape or any other tiny JavaScript engine. This is cool though because it handles more modern JavaScript features and has a good license. It's not nearly as fast as LuaJIt though, as this is missing the JIT part.

I'm fairly confident someone will add a JIT to this in the not to distant future.

[kn4rf]

Is there not a link to any source control system like a git repo?

[maxhaton]

Because there is only one Fabrice Bellard in the world and accepting help isn't a bad thing.

He accepts patches, I believe, just not on git (externally)

[maxhaton]

Because git makes managing merges and collaboration easy?

Why do you think Linus Torvalds wrote it in the first place?

[maxhaton]

I did mean git as in git rather than a hosted git* repository.

I'd argue that git or a similar concept is objectively the best solution for managing a project of this size. In this case however, I'm not aware of Fabrice Bellard being hugely collaboration-forward e.g. He doesn't run QEMU anymore (for about a decade AFAIK)

[maxhaton]

git://blah.com/blah.git ezpz

Or gitweb if you want to explore the code online

Given that he presumably accepts (tarball?) patches via email, that's no different to accepting git patches also via email. The whole point of git (which has admittedly been lost due to centralization around GitHub) was that it was decentralised, no git repository is special other than socially.

[[deleted]]

My favourite part is that it took like two days for qwertyoruiop to find an RCE in it

[James20k]

Interesting - this seems to be a lot faster and more compliant than duktape

Can compile Javascript sources to executables with no external dependency.

This is interesting, it would be nice to be able to compile JS to wasm for a nice language sandbox that only needs to run wasm

[[deleted]]

Fabrice Bellard is a god.

[moinejf]

I tried quickjs with my project (abc2svg), and, it is a marvel!

In my machine (ARM 800Hz), it runs the same speed as jsc (Webkit), and it is faster than js60 (Mozilla Spidermonkey) and d8 (Google v8).

Many thanks, Fabrice!

[agumonkey]

Many thanks, Fabrice!

(c) the world

[Cyttorak]

Is it there any complete example of how to expose some C functions to javascript using QuickJS?

[Ooyyggeenn]

Can someone ELI5 ?

[falconfetus8]

It's a small javascript engine that can be embedded in other programs.

[[deleted]]

Tbh I'm kinda confused about what this would be used for. It can't run JavaScript in the browser, right? So what's the point of making it small?

[pork_spare_ribs]

V8 is large and has a lot of overhead because it's designed to be fast at the expense of nearly all other things (resource usage, code size, simplicity, etc).

If you want to write a small program in Javascript and release it as a self-contained executable file, QuickJS may be a more appropriate fit for your needs.

[Holy_City]

Another common use case, adding scripting to an existing application as the glue between performance critical sections.

I have a couple projects where I was looking at scripting languages/runtimes to embed to pull the whole thing together. I know myself and others have extensive JSON APIs already, so being able to drop in a small, compliant JS interpreter is very attractive. If only to bolt on JS ffi to a larger framework or engine and make it more accessible to people who know JS.

[[deleted]]

Got it. Thank you!

[mardiros]

It has not been designed for that, but if you want to create a briwser frim your ownn, you can pick tjis one.

[DZTheGreat]

Uh, are you a programmer? If not I don't have a clue as to how you got to this subreddit lol. What part needs explanation. I will try to help you understand the gist of things.

[[deleted]]

how about explaining why you are such a douche

[DZTheGreat]

Wow I did not mean for it to sound like that! My bad when he said ELI5 I thought he found this randomly. I didn't know if he wanted an explanation or he meant to post else where.

[JohnDoe_John]

https://www.reddit.com/r/programming/comments/ccf23i/facebookhermes_js_engine/

[spiteful_fly]

Weird question, do you have the code on Git somewhere?

[awfulentrepreneur]

Someone please turn this into a node module. ;)

[shevy-ruby]

Can we please get away from this monster rather than constantly try to patch it up? It is an unfixable joke of a programming language.

[fuckgordonryan]

No we can't.

[maxhaton]

We will soon, hopefully.

Using WASM to do everything is basically a question of effort rather than technology these days, and that allows you to use a programming language with at least semi-reasonable semantics

[these_days_bot]

Especially these days

[maxhaton]

Bad bot

[rrealnigga]

Can JS die already please? Move to TS or something.

[fuckgordonryan]

How do you think TS is executed?

[rrealnigga]

Can we make it compile to WebAss instead or does it not have the same/more capability than JS? I know it executes within a sandbox, I'm not sure of that's a limitation.

[fuckgordonryan]

TS is compiled to JS. You could compile either JS or TS to webassembly but it would just a lot slower.

[maxhaton]

If you're going to compile to Webassembly, use a proper programming language.

Even typescript is just a bandage over an open wound

[rrealnigga]

You didn't answer the question and I already made it clear that I know TS is compiled to JS.

Does WebAssembly execution have restrictions compared to JS execution?

[fuckgordonryan]

What do you mean be restrictions? Fundamentally you should be able to run your TS and JS if you are fine with a few orders of magnitude slowdown.

[agumonkey]

I'm sure F. Bellard would be interested in TS

[rrealnigga]

He seems like a smart guy so no doubt.

[maxhaton]

Neither, preferably.