Show HN: Astra – a new js2exe compiler
25 comments
·May 20, 2025zamadatix
Very interesting. The readme notes "Different than the others - Astra is a new approach to compiling JavaScript/TypeScript applications. It uses a different method than other compilers like pkg or nexe." but never really explains what the difference is. Is it just that the code is run through esbuild before the SEA step or is there some other "magic sauce"?
Vorh
Looks like a good start. A few notes:
- The first thing on the "features" list should be something that other compilers cannot do. Esthetics (maybe just say "DX"?) is a nice to have - sometimes VERY nice to have - but should not be positioned as the most important item.
As the original post says the alternatives have poor ESM support - that's a good differentiator.
- Even though ES Modules are part of the ECMAScript standard, having a header stating "(Partial) Support for ECMAScript"- to me, at least - indicates the project does not support base JS features, not that ESM imports have problems. Maybe say "improved ESM support"?
- Docs seem a little bare. For example, the Usage section says:
# Preinstall Node.js on the target machine
astra install
Also, no mention of binary limitations in actual docs, despite mention in post.
Hopefully this does not come off as discouraging - this looks like a good project.
qwertycodepl
Thanks for the feedback! I'm constantly working on the project. It's hard to do bc node sea is still an experimental feaurte and there's no much documentation about it, and i want to make it highest quality possible. And it's my first open-source project what's actually getting attention. I would really appreciate any help with this project!
dpcan
This is really interesting, got it up and running very quickly.
I'm not sure what the use case is and it doesn't auto-load chromium with its own web server from what I can tell. Is it just for creating javascript CLI utilities?
jasonjmcghee
To understand the underlying architecture- is my understanding correct that this runs esbuild to bundle then bundles that with node runtime and creates a binary that executes "node index.js"?
qwertycodepl
yes but it uses node SEA you can read about it here: https://nodejs.org/api/single-executable-applications.html
quotemstr
This is not a compiler. It is doing no program translation. No register allocation. No parsing. No linking. It in no way resembles a compiler. Not every program that produces an executable file is a compiler just because some programs you may have heard of, like gcc, are in fact compilers.
I wish the JS universe would stop inventing new and wrong names for things.
(That said, this thing is at least using postject for actual insertion of the payload blob into the target executable, and based on its README, postjecth as the good taste to embed data as PE/ELF/Mach-O sections instead (as Bun does) of just YOLOing the attachment with cat.)
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TheRealPomax
You probably want to put that information in your README.md, because there is barely any information in the readme, and the docs look to be a placeholder atm =)
qwertycodepl
thanks :)
belmarca
I clicked on this hoping for an actual compiler. However from what I can see this is a bundler. The name is confusing.
qwertycodepl
Thanks for the feedback! You're right - Astra is technically a bundler-to-executable tool, not a source-level compiler like Babel or TypeScript.
I called it a “compiler” in the sense that it transforms a JS project into a standalone .exe, similar to how tools like pkg or nexe are often described. That said, I’ll consider clarifying that in the description to avoid confusion. Appreciate the comment!
ymsodev
Honestly, I would drop calling compiler altogether -- it's just not a compiler. It doesn't make it any less cool though!
quotemstr
Blame bun's --compile flag: https://bun.sh/docs/bundler/executables
We're probably going to have to live with "compiler" meaning "bundler" as an ongoing JavaScript-world neologism.
qwertycodepl
yeah it's not but i don't know how to call it. if i say it's bundler it will be more confusing in my opinion. waiting for your suggestions!
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thot_experiment
> Average exe is ~70-80MB (depends on your code) so it's lighter than most compilers
I know it's JS not actually a compiler but a bundler that just packs node in with your code, but I still had a nice laugh at 80mb being light. I suppose that's where the overton window is in a world of 1gb node_modules folders.
I wish there was a middle ground between this sort of thing and QuickJS (which is actually light, but has a lot of rough edges when it comes to its filesystem and network interfaces)
TimTheTinker
Bun also supports this out of the box, and the overhead is likely a bit less (reportedly 30-40MB for a single `console.log` call with no further dependencies - I didn't verify that myself though).
https://bun.sh/docs/bundler/executables
I suspect a large portion of the executable size in both cases is for the ICU library for localization support (Note QuickJS has its own, much smaller l10n library.) It's possible to download a Node binary without ICU, which could trim ~30MB.
zamadatix
> reportedly 30-40MB for a single `console.log` call with no further dependencies - I didn't verify that myself though
I got a 110 MB exe for "console.log('test')" in "test.ts" using "bun build .\test.ts --compile --outfile test.exe". Pretty compressible though, on the order of 1/4th the size pretty easily. Considering it has zstd compression for sourcemaps that'd be an interesting option to add in.
martinsnow
What's light enough when the average user in the western hemisphere has +300gb of storage?
I'm just asking since a 512gb disk has become the standard when ordering a laptop.
CleanCoder
The amount of functionality an application provides should be the benchmark for the size rather than one's available disk space. I'm sitting on 20TB+ of available storage and anything over 1MB for a simple "Hello World" is excessive.
johnisgood
Well, if we already could make something in 1 MB, why do we want to achieve the same thing with 100 MB? It is as if there is a mentality of "somehow the higher the size the better".
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luukfromaustria
[flagged]
Hi everyone I'm new here and i wanted to introduce my project i've been working on. Astra is a simple but powerful node.js to exe compiler. It uses esbuild and Node SEA. It uses postject to inject your code to nodejs binary. It focuses more on compiling cli and Servers like pkg or nexe (express) than fullstack applications like electron or tauri. It has rich ESM and typescript support. It has good DX and cli UX. I made it bc i didn't like using pkg or nexe, they cause a lot of problems with esm.
LIMITATIONS: Now it has problems compiling projects with depencides containing binaries (e.g. bcrypt, rcedit), and it compiles only for Windows but i'm working on it
If you like it, leave a and comment what you think about it!