RN
The Future of Rust Web Applications - Greg Johnston
@ Rust Nation UK
02/26/25
Takeaways
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Greg Johnston
02/26/25
@ Rust Nation UK
I'm Greg Johnston, the creator of Leptos, and I'm here to discuss the future of web applications written entirely in Rust.
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Greg Johnston
02/26/25
@ Rust Nation UK
Leptos is an open-source project built by the community for fun, not a startup trying to sell anything.
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Greg Johnston
02/26/25
@ Rust Nation UK
Today, I want to explore the past, present, and future of Rust in web application development, focusing on frameworks like Leptos and Dioxus.
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Greg Johnston
02/26/25
@ Rust Nation UK
I want to address the question: Is there a future for interactive web applications written entirely in Rust?
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Greg Johnston
02/26/25
@ Rust Nation UK
When I talk about Rust on the web, I'm not discussing building web infrastructure or API services; I'm focusing on using Rust for interactive web applications.
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Greg Johnston
02/26/25
@ Rust Nation UK
The web allows you to use any programming language to create applications, and while JavaScript is common, Rust can also be a viable option.
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Greg Johnston
02/26/25
@ Rust Nation UK
Rust is a fine language for modeling complex domains, and I prefer using it over JavaScript for certain applications.
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Greg Johnston
02/26/25
@ Rust Nation UK
The foundational crates for building Rust web applications include WM Bindgen and WebSys, which facilitate interaction with JavaScript and browser APIs.
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Greg Johnston
02/26/25
@ Rust Nation UK
Leptos is a mature front-end framework in Rust, designed for stability and focusing on web standards and progressive enhancement.
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Greg Johnston
02/26/25
@ Rust Nation UK
Dioxus is another interesting framework that focuses on desktop and mobile app development using web technologies, allowing for native-like applications.
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Greg Johnston
02/26/25
@ Rust Nation UK
The current limitations of using Rust for web applications include compile times, binary sizes, and the ecosystem surrounding Rust web development.
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Greg Johnston
02/26/25
@ Rust Nation UK
Compile times in Rust can be slow, which affects the speed of iteration during UI development, making it challenging to see changes quickly.
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Greg Johnston
02/26/25
@ Rust Nation UK
Binary sizes in Rust can be problematic because each compiled Rust application includes its own standard library, leading to larger file sizes compared to JavaScript applications.
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Greg Johnston
02/26/25
@ Rust Nation UK
JavaScript frameworks require a large amount of code to be shipped, which can cost companies millions in loading time, making them less appealing for e-commerce applications.
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Greg Johnston
02/26/25
@ Rust Nation UK
Achieving high performance scores, like 100 on Lighthouse, can be done without using advanced techniques; it's possible to optimize the overall size of your application and load it over time.
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Greg Johnston
02/26/25
@ Rust Nation UK
WebAssembly and JavaScript have different costs in the browser; JavaScript is interpreted and must be fully downloaded and parsed, while WebAssembly is designed for streaming compilation, making it faster to load.
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Greg Johnston
02/26/25
@ Rust Nation UK
The cost of running a WebAssembly app is primarily the cost of downloading it, and even a minimal WebAssembly application can be quite small, often in the dozens of kilobytes.
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Greg Johnston
02/26/25
@ Rust Nation UK
In server-side rendered applications, the time to interactive is proportional to the amount of content on the page, meaning more content can slow down loading and interactivity.
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Greg Johnston
02/26/25
@ Rust Nation UK
Partial hydration, also known as the Islands architecture, allows for only certain parts of a page to be hydrated, improving performance by reducing the amount of code sent to the browser.
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Greg Johnston
02/26/25
@ Rust Nation UK
Using Islands architecture, you can hydrate only the interactive parts of a page, which can significantly reduce the amount of WebAssembly shipped to the user's browser, leading to faster load times.
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Greg Johnston
02/26/25
@ Rust Nation UK
By switching to Islands for interactive components, you can achieve a 75% reduction in the size of the application, which can lead to a fourfold improvement in loading time.
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Greg Johnston
02/26/25
@ Rust Nation UK
Dynamic linking in Rust has historically been challenging, but recent advancements are enabling better code splitting and lazy loading, which can improve performance in web applications.
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Greg Johnston
02/26/25
@ Rust Nation UK
The Rust ecosystem offers unique advantages, such as exhaustive pattern matching and result types, which can enhance development compared to the JavaScript ecosystem.
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Greg Johnston
02/26/25
@ Rust Nation UK
There is a future for interactive web applications written in Rust, and contributions to projects like Leptos are welcome to help advance the ecosystem.
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Greg Johnston
02/26/25
@ Rust Nation UK
AI can assist in generating boilerplate code for front-end development, but its effectiveness may vary depending on the specific tools and frameworks being used.
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Greg Johnston
02/26/25
@ Rust Nation UK
WebAssembly currently cannot directly call browser APIs due to its sandboxed nature, requiring data to be passed through JavaScript, which can introduce latency.
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Greg Johnston
02/26/25
@ Rust Nation UK
Future improvements in Rust and WebAssembly may allow for more efficient interactions with browser APIs, but significant challenges remain in achieving this.