Martin Stewart (Aug 13 2021 at 22:05): Martin Stewart (Aug 13 2021 at 22:05):When compiling a program, how large is the generated binary file? Is it small enough that it would be reasonable to make websites with it? Assuming that it's possible to target WASM in the future.
Folkert de Vries (Aug 13 2021 at 22:27):it should be, it's a bit like Rust or C (and nothing like e.g. haskell, which has to bring along its whole runtime system)
Folkert de Vries (Aug 13 2021 at 22:29):in terms of code size it's not as good as the current elm -> wasm project (cc @Brian Carroll ) because we fully monomorphize while that wasm conversion generates something that is still more dynamic in nature
Folkert de Vries (Aug 13 2021 at 22:29):but cool things are already happening with wasm in zig/c/rust so yea it should be feasible
Brian Carroll (Aug 13 2021 at 22:37):That's true, my generated Wasm is pretty much untyped so only one copy of List.map for example, and that's good for size. (There are other things bloating up the code size at the moment but that will all get removed eventually!)
Richard Feldman (Aug 13 2021 at 22:44):also it might require being careful on the platform side - e.g. there are various special things you have to do to get hello world in Rust wasm down to 2.4k:
https://kripken.github.io/blog/binaryen/2018/04/18/rust-emscripten.html
Brian Carroll (Aug 13 2021 at 22:58):Interesting! Yeah the complicated parts of the Wasm platform for me have been about the interface with JS. You need to encode and decode your data structures, you need to write a Wasm stack frame from JS when you call a function, you have different memory managers on each side with cross-references between them (which makes lifetimes complicated), etc. There's some overhead for all of that.
Folkert de Vries (Aug 13 2021 at 23:01):is that inherent or just the current state of the wasm stack/browser integration?
Brian Carroll (Aug 14 2021 at 07:41):It's inherently hard but it's possible, and there are proposals in the works. But I first checked the status 3 years ago and it is still in stage 1 today. There's an explainer doc here and the list of proposal statuses is here
Brian Carroll (Aug 14 2021 at 07:49):It would allow Wasm to refer to values owned by the platform, and the platform would handle the memory management. I think the hard part is that the web standards are not defined in terms of integers and floats, but higher level types like DOMString and Regex and Promise and a hundred other things with implementation-defined memory layout.
Martin Stewart (Aug 14 2021 at 09:56):Cool, sounds like support is a ways off due to both Roc and WASM being in development. Still, I think it would be fantastic if one day I could write code that could be used on the backend as well as web apps, desktop apps, and mobile apps, without needing resort to Electron and Node or something low level like QT.
Folkert de Vries (Aug 14 2021 at 09:59):yea share the vision, lots of work that needs to be done to make that ergonomic, but it all should be possible in theory
Lucas Rosa (Aug 14 2021 at 10:59):I actually let go of write once, run anywhere as a goal. Every manifestation seems to be hacky and never respect the platform well enough. It’d be interesting to see if roc can break that. But I imagine it’d still be a separate roc platform for each (mobile, web platform, desktop native graphics) and then for app devs they just use roc
Lucas Rosa (Aug 14 2021 at 11:01):For web, I’m also increasingly less excited about wasm with each year that passes. But on the roc side of things a platform for the web could emit javascript and wasm based off functions and types the app dev uses that the platform needs to consume. Instead of roc itself compiling to wasm
Folkert de Vries (Aug 14 2021 at 11:01):what makes you less excited for wasm on the web? just the hype dying down or are there technical reasons?
Lucas Rosa (Aug 14 2021 at 11:02):seems to be only hype so far
Folkert de Vries (Aug 14 2021 at 11:02):i know for a fact that it's used a bunch outside the web
Lucas Rosa (Aug 14 2021 at 11:02):then I search for rust web frameworks and find 5 competing frameworks all inspired by Elm architecture
Folkert de Vries (Aug 14 2021 at 11:02):my theory: the wasm tooling is built by non-web people
Lucas Rosa (Aug 14 2021 at 11:03):And I end up thinking “ok here we go again, frontend framework wars the rust version”
Lucas Rosa (Aug 14 2021 at 11:04):i know for a fact that it's used a bunch outside the web
nice, any cool examples?
Lucas Rosa (Aug 14 2021 at 11:04):Also don’t get me wrong. I’m not saying roc shouldn’t compile to wasm
Lucas Rosa (Aug 14 2021 at 11:05):but I do think a separate Lang just for web and wasm (or a roc platform), with NextJS features sprinkled on top is what the world needs
Folkert de Vries (Aug 14 2021 at 11:06):it's NDA'd but the vague idea is that you can just send a bunch of code to a remote device and execute it there and be sure that it's safe
Folkert de Vries (Aug 14 2021 at 11:06):because of the sandboxing
Lucas Rosa (Aug 14 2021 at 11:06):slick
Folkert de Vries (Aug 14 2021 at 11:06):and that's really nice if you have a lot of machines in the field and want to make a software update
Lucas Rosa (Aug 14 2021 at 11:07):seems like a killer feature for IoT stuff
Lucas Rosa (Aug 14 2021 at 11:07):wasmtime or something to execute I imagine
Folkert de Vries (Aug 14 2021 at 11:07):yea, so you need a somewhat capable machine for this
Folkert de Vries (Aug 14 2021 at 11:08):but most machines are in that category these days
Folkert de Vries (Aug 14 2021 at 11:08):if you can run a botnet on it, then it can run this probably
Folkert de Vries (Aug 14 2021 at 11:08):so fridges ect :smile:
Lucas Rosa (Aug 14 2021 at 11:08):lmao that reminds me of that famous mirai hack
Folkert de Vries (Aug 14 2021 at 11:09):consumer IOT is very bad...
Folkert de Vries (Aug 14 2021 at 11:09):b2b though is pretty interesting
Lucas Rosa (Aug 14 2021 at 11:09):interesting
Lucas Rosa (Aug 14 2021 at 11:09):well that gives me a more positive outlook
Folkert de Vries (Aug 14 2021 at 11:11):well the tooling is the hard part here for the web
Folkert de Vries (Aug 14 2021 at 11:11):plus you have to compensate for bigger binary size
Lucas Rosa (Aug 14 2021 at 11:11):give me direct DOM access!
Folkert de Vries (Aug 14 2021 at 11:12):well, yes
Lucas Rosa (Aug 14 2021 at 11:12):lol I think there’s a proposal but as it was said above that’s tricky
Folkert de Vries (Aug 14 2021 at 11:12):not sure why that is taking so long, seems pretty fundamental
Lucas Rosa (Aug 14 2021 at 11:14):I think Brain said it well.
I think the hard part is that the web standards are not defined in terms of integers and floats, but higher level types like DOMString and Regex and Promise and a hundred other things with implementation-defined memory layout.
Lucas Rosa (Aug 14 2021 at 11:20):UI is in a strange state of affairs and it doesn’t help that Apple and Android don’t play nice. At least they have react inspired ways of building now with SwiftUI and Jetpack Compose
Martin Stewart (Aug 14 2021 at 18:02):Lucas Rosa said:
I actually let go of write once, run anywhere as a goal. Every manifestation seems to be hacky and never respect the platform well enough. It’d be interesting to see if roc can break that. But I imagine it’d still be a separate roc platform for each (mobile, web platform, desktop native graphics) and then for app devs they just use roc
To be clear, I'm interested in being able to reuse some code (but not all). You're right that it is a bad idea to try reusing all code between different devices, but usually there is a chunk of code (shared datastructures, validation, helper functions, etc) that want to be able to use on frontend apps and on the backend.
Lucas Rosa (Aug 14 2021 at 22:31):nice totally makes sense
Lucas Rosa (Aug 14 2021 at 22:32):In terms of roc, I imagine there’s a fair bit of helper functions and shared code that can be intentionally platform agnostic. That way no matter how many base platforms you need for various apps as part of your stack, you could still get one of the best code re-use experiences there is out there
Lucas Rosa (Aug 14 2021 at 22:35):In a way I think I might be trying to say that maybe roc can be better than wasm for code re-use. Would a world with great roc success even care as much about wasm? Obviously still probably yes but I wanted to be dramatic lol
Lucas Rosa (Aug 14 2021 at 22:46):As an example. Maybe I have some app. It has an API, a web frontend, a desktop app, and a CLI interface. Those 4 things could all be a different platform. Maybe the API is a platform for building graphql backends on top of postgres. Maybe the web frontend platform does some fancy ssr and client rendering by emitting JS/wasm at run time. Maybe the desktop app is a UI platform built using native graphics or even just an SDL wrapper. And then the CLI platform handles capturing commands with a nice dsl. All the data types representing your domain and common transformations of these could be stuffed in a platform agnostic shared package to be used across every platform you need.
Last updated: Jul 26 2025 at 12:14 UTC