canonic VS rsocket-java

I just founded a company where we're building a cross-platform native desktop app. Perhaps given we're on HN we can scope this to ask why aren't any _startups_ building native desktop apps?

It's something I wonder about as well. We're building real-time performance critical software, so we don't have much of an alternative. Given these constraints, we also ruled out Electron, Avalonia, React Native early on.

We're using Qt Quick which doesn't get nearly the love it should. I was a web developer for 5 years in a past life, and I'm pretty blown away by how pleasant and well-designed Qt Quick's QML language is. One of our team members created Canonic, https://www.canonic.com to explore how the web might look if QML was used as the document markup for the web.

The popular opinion around Qt Quick is that it is best suited for mobile or embedded projects with a dynamic UI, animations, etc. But over the last few years, it has really become a great desktop solution – to the point where Qt put Widgets into maintenance mode and is focusing efforts on Qt Quick across desktop, mobile and embedded targets.

With Qt 6, the GUI is drawn using native graphics acceleration: Metal on macOS, DirectX11 on Windows, Vulkan on Linux. This makes it really easy to bring in a texture you're drawing in some other piece of code outside of Qt. As a result, the QtMultimedia framework in Qt6 is zero-copy on most platforms with the FFmpeg backend. Frames get decoded if a GPU HW decoder is available, then this texture can be read directly by QtQuick and then rendered by the display server without ever being copied. I don't think there's a single other cross platform framework out there that achieves the same level of usability, performance and easy access to platform native APIs.

Here are just a few non-trivial desktop apps that come to mind using Qt Quick:

- Denon Engine DJ - https://enginedj.com/

Here's the website if you want to test it out: https://www.canonic.com

No, the end goal is to have an entirely separate browser which browses website built with all instead of html / js / css ; since Qt compiles to WASM it's a simple way to try it but the actual thing exists as a standalone desktop app: https://github.com/canonic/canonic

GitHub repo: https://github.com/canonic/canonic

TL;DR: WasmRS is an implementation of RSocket for WebAssembly giving you reactive, async streams in and out of WASM modules. GitHub | Protocol details | Rust source | Go source

You might also checkout https://rsocket.io/

My personal WebSockets vs SSE TL;DR goes something like this:

* If you're on HTTP/2, start with SSE

* If you need to send binary data, use WebSockets

* If you need fast bidi streaming, use WebSockets

* If you need backpressure and multiplexing for WebSockets, use RSocket or omnistreams[1] (one of my projects).

[0]: https://rsocket.io/

[1]: https://github.com/omnistreams/omnistreams-spec

A few years ago I was more inclined to use WebSockets. They're undeniably cool. But as implemented in browsers (thanks to the asynchronous nature of JavaScript) they offer no mechanism for backpressure, and it's pretty trivial to freeze both Chrome and Firefox sending in a loop if you have a fast upload connection.

I designed a small protocol[0] to solve this (and a few other handy features) which we use at work[1]. A more robust option to solve similar problems is RSocket[3].

More recently I've been working on a reverse proxy[2], and realized how much of a special case WebSockets is to implement. Maybe I'm just lazy and don't want to implement WS in boringproxy, but these days I advocate using plain HTTP whenever you can get away with it. Server Sent Events on HTTP/1.1 is hamstrung by the browser connection limit, but HTTP/2 solves this, and HTTP/3 solves HTTP/2's head of line blocking problems.

Also, as mentioned in the article, I try to prefer polling. This was discussed recently on HN[4].

[0]: https://github.com/omnistreams

[1]: https://iobio.io/2019/06/12/introducing-fibridge/

[2]: https://boringproxy.io/

[3]: https://rsocket.io/

[4]: https://news.ycombinator.com/item?id=27823109