Discussion

Reactive Apps withEffortless Performance.

sourcegrift: Looks very good and probably will be my library of choice for my next web project.For desktop, I'm very happy with qmetaobject-rs. Qt is time tested and highly reliable. And gui is, frankly, serious business.Also, Generally speaking, UI itself is best done declaratively rather than imperatively. There's a reason quick is adopted more than qwidgets.

silon42: For simple stuff, qml is OK/better (except the JS part)... but for some more complicated views I'd want qwidgets.

conceptme: a UI library needs some demo

lukechu10: The website itself is made with Sycamore!There are also a bunch of examples at https:&#x2F;&#x2F;github.com&#x2F;sycamore-rs&#x2F;sycamore&#x2F;tree&#x2F;main&#x2F;examplesYou can see the deployed versions at https:&#x2F;&#x2F;examples.sycamore.dev&#x2F;<example name>&#x2F; for instance: https:&#x2F;&#x2F;examples.sycamore.dev&#x2F;todomvc&#x2F;

silon42: I get: Uncaught (in promise) ReferenceError: WebAssembly is not defined

embedding-shape: The website mentions "giving you full control over performance", what are those knobs and levers exactly? What does those knobs and levers influence, and what sort of tradeoffs can you make with the provided controls?

lukechu10: Unlike other UI libraries, I would say Sycamore has a very clear execution model. If you've used something like React before, there is all this thing about component lifecycles and hook rules where the component functions run over and over again when anything changes. This can all end up being fairly confusing and has a lot of performance footguns (looking at you useRef and useMemo).In sycamore, the component function only ever runs a single time. Instead, Sycamore uses a reactive graph to automatically keep track of dependencies. This graph ensures that state is always kept up to date. Many other libraries also have similar systems but only a few of them ensure that it is _impossible_ to read inconsistent state. Finally, any updates propagate eagerly so it is very clear at any time when any expensive computation might be happening.For more details, check out: https:&#x2F;&#x2F;sycamore.dev&#x2F;book&#x2F;introduction&#x2F;adding-state

bickfordb: The Dioxus library seems really similar to me. How is Sycamores model different?

lukechu10: Dioxus originally was more like ReactJS and used hooks. However, they have since migrated to using signals as well which makes Dioxus and Sycamore much more similar.One remaining major difference is that Dioxus uses a VDOM (Virtual DOM) as an intermediary layer. This has a few advantages such as more flexible rendering backends (they also support native rendering for desktop apps), at the cost of an extra layer of indirection.Creating native GUI apps should also be possible in Sycamore, and something I'm interested in although there is currently no official support. However, I think one of the big differences with Dioxus would be that Dioxus supports "one codebase, many platforms" whereas I think that is a non-goal with Sycamore. Web apps should have one codebase, native apps should have another. Of course, it would still be possible to share business logic but the actual UI code will be separate.

electrograv: IMO a UI library landing page should always contain a screenshot example of the UI.I can’t find a screenshot of it anywhere, let alone the landing page.

TechSquidTV: Unless maybe it's headless, then I still expect a component library or something. Still, I see nothing.

catapart: in case you don't understand what GP is suggesting: your website does not actually describe what you're providing. A "next generation Rust UI library powered by fine-grained reactivity." could mean a UI for native apps - something like egui or Dioxys - or it could mean a way to use rust to output HTML, CSS, and javascript. Or a bunch of other things. And, regardless, there's no way to look at your website and determine how to get that output using sycamore. I can inspect and see your HTML or your CSS, but there's no Rust code for me to compare that against without going and looking it up somewhere.To be more succinct: you don't even have an image of your UI running on your websites landing page. Not one single image of the library which is, again, a UI library. People have an interest in knowing "does this look and feel like I want it to?" as well as "can I use this in the projects I'm working on?". Both of those questions should be answered by your landing page. For me, at least, it doesn't do that.

lukechu10: Hmm thanks for the feedback. The front page definitely has lots of room for improvement.

fnikacevic: A great example is the shadcn sitehttps:&#x2F;&#x2F;ui.shadcn.com&#x2F;Shows you how good it looks out of the box on the first page.

mapcars: With Tauri you also get the freedom of choosing frontend frameworks and can reuse existing frontend code&#x2F;skills. Yes React has issues, for example Svelte handles reactivity in a much better way. I don't see real benefits of re-implementing the whole thing in Rust.

josephg: It looks like this is a web UI library, so it would just render using regular html.I wish they said that on the homepage. I assumed it could render to the desktop or something, and I had to read tea leaves to figure that out.

dewey: In the footer: "This website is also built with Sycamore. Check out the source!" https:&#x2F;&#x2F;github.com&#x2F;sycamore-rs&#x2F;website

arpadav: i've had my shot at sycamore a number of times. IMO leptos (leptos.dev) has far more fine-grained capabilities, and dioxus (dioxuslabs.com) is overall more hand-holdy but also powerful. comes with tradeoff for speed. wasm still isnt there yet (yet..) but a lot more web frameworks (including smaller rust ones) can be tracked here: https:&#x2F;&#x2F;krausest.github.io&#x2F;js-framework-benchmark&#x2F;current.ht...

cma256: I really like these projects but missing from them is genericity. If you're taking the time to build a WASM app in Rust it would be nice if that app could compile to something other than WASM. For example, looking at the sycamore website's source I see p, h1, div, etc. What I'd rather see is "row", "column", "text". In their source I see tailwind what I'd rather see is "center", "align right", etc.In other words, elm-ui but for these WASM Rust apps. Building a mobile app, a desktop app, and a web app, in my mind, should be accomplish-able given the right primitives (without requiring a JavaScript runtime be bundled). Rust's multi-crate workspaces make it a really great candidate for solving these cross-platform problems. IMO of course.

gwbas1c: > Reactive Apps with Effortless Performance.> Sycamore is a next generation Rust UI library powered by fine-grained reactivity.It's not clear on the landing page that this is for in-browser UI, as opposed to desktop UI and&#x2F;or mobile UI.I would make it completely unambiguous that Sycamore is for web applications.

lukechu10: Ok I've modified it slightly.But Sycamore does have ambitions to have native GUI support as well. I'm currently looking at GTK, Iced, and GPUI and see if it would be possible to add Sycamore support. This would make it possible to create GTK, Iced, or GPUI apps using building blocks from Sycamore.

0x3f: I think if you're going to use Rust on front end you're probably going to use it on back end too. In that case, I would just use Dioxus and get the e2e typing for free. What would be the benefit of Sycamore?I wouldn't recommend e2e Rust generally yet though. I think server&#x2F;API + web could work, but mobile is just boiling the ocean and will never be as good as native. You might think you can just use it for server and API, then do mobile native apps, but actually the escape hatches are not great.Sad to say but "just use React" remains the good advice.

airstrike: [delayed]

truefaxxx: A word to the wise: similar to how foam is mostly air, Tauri is mostly marketing. Most of those 15MB "lightweight" bundles expand to 2 GB+ RAM in practice. Of course, devs still shamelessly (ignorantly, in all likelihood) call the apps "lightweight", while taking up, say, 6 GB of RAM for a 5 button UI. Tauri have also proven reticent [0] to correct the record. One supposes the sole advantage of sharing memory with other Tauri apps is not a sufficient sell to overcome Electron's single-browser-engine advantage.A pure Rust app takes up ~60 MB for the same UI, with a large portion of that going towards graphics (wgpu table stakes).[0] https:&#x2F;&#x2F;github.com&#x2F;tauri-apps&#x2F;tauri&#x2F;issues&#x2F;5889

wsowens: I looked briefly, but is anyone aware of the differences between Yew[1] and Sycamore[2]? Presumably they are both Elm-influenced(?) Rust web UI libraries named after trees, but it's unclear to me why I should use one versus the other.1. https:&#x2F;&#x2F;github.com&#x2F;yewstack&#x2F;yew2. https:&#x2F;&#x2F;github.com&#x2F;sycamore-rs&#x2F;sycamore

0x3f: If you're not targetting mobile, why diverge from XHTML at all?

cma256: Are there native frameworks which use XHTML? Regardless, a document language being used to construct complex, interactive GUIs is incidental complexity. XHTML can be a compilation target but it does not need to be a development target.

0x3f: But what's the benefit of using e.g. <row><cell> over <tr><td> if your only target is the web?

cma256: If your only target is web then there is no benefit other than a reduction in complexity.For example, a "row" is not just a "<div>" tag. Its a div which horizontally fills its container. Centering contents with a "center" style attribute abstracts flex-box, browser compatibility, version compatibility, and the cascading behavior of CSS.You move the incidental complexity of the web platform into the compiler which will always do the right thing. And in exchange you get the option to compile to a native or mobile app for "free".

lukechu10: I'm personally not to big of a fan of the Elm pattern for UI. Although it can be quite elegant, most of the times, it ends up being quite verbose even for simple things.I feel like combining the drawing layer from one of these existing native UI frameworks with Sycamore could be interesting in reducing some of the boilerplate with GTK, Iced, GPUI, etc...