Building ambitious software — Jonathan Kelley, Dioxus Labs & Cognition
Jonathan Kelley, founder of Dioxus Labs, shares insights from building a cross-platform Rust app framework for five years. He details Dioxus's evolution, its core technologies like Blitz and Subsecond, and the transformative impact of AI coding agents. Kelley explains how AI excels at handling Rust's complexity, automating mundane tasks, and serving as patient specialists for knowledge-intensive problems, yet falls short in writing effective tests. He concludes that while AI makes code cheap, quality remains paramount, shifting the engineer's focus to architecture and strategic system design.
The Dioxus Journey: Ambitious Software and the Age of AI Coding Agents
Jonathan Kelley, founder of Dioxus Labs, shares his team’s journey of building an ambitious software project and the profound impact of AI coding agents on their development process.
Inception and Evolution of Dioxus
Kelley initiated Dioxus five years ago as an undergraduate, driven by the vision of creating a cross-platform app framework using Rust, HTML, and CSS. His motivation stemmed from Rust’s native performance, robust type system, and straightforward cross-compilation, aiming to overcome limitations prevalent in existing solutions like React Native and Flutter. The early years were marked by significant challenges, as the team had to build almost every component from scratch—including reactivity systems, font rendering, hot reloading, and application bundling.
Today (as of the presented 2026 perspective), Dioxus has far surpassed its initial goals, boasting nearly 37,000 GitHub stars and an estimated 200 million cumulative end-users. It enables the creation of full-stack web, iOS, and Android applications from a single Rust codebase, deployed in diverse applications ranging from AI assistants and voting software to satellite collision avoidance systems.
Core Dioxus Technologies
Two pivotal technologies underscore Dioxus’s capabilities:
- Blitz Rendering Engine: A lightweight yet fully-featured HTML and CSS rendering engine. It integrates a browser-grade CSS engine extracted from Firefox, a custom HTML DOM, and a hybrid GPU rendering pipeline. Blitz applications are remarkably efficient, typically under 5MB in bundle size and consuming less than 50MB of RAM, in stark contrast to more resource-intensive frameworks like Electron.
- Subsecond Hot Reload Engine: A unique, generic hot reload engine designed for Rust, C, and C++. This technology allows live patching of running native applications in approximately 100 milliseconds, showcasing wide language and runtime support, including WebAssembly. Kelley notes that achieving this level of broad support for native compiled code hot reloading was an unprecedented technical feat.
The Impact of AI Coding Agents
Initially skeptical, the Dioxus team experienced a significant shift when AI coding agents demonstrated exceptional proficiency in Rust. This newfound capability led to an initial