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I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Charlie Cheever retweeted
The way to think about Exact is the agent-native way to write high-performance native apps. @ccheever *doesn’t* describe Exact as cross-platform in his launch post.
In the agentic era every team is empowered to build apps that reach their users everywhere they are. Your agent can write N versions of your app with Exact or anything else for N platforms. When N is a large number of target platforms - and platforms add new intrinsic complexity like iPhone Duo - it is taxing to multiply your token cost by N.
Every company is using agents to build faster on their traditional codebases. They are working on faster horses and, in some cases, N horses.
Exact is the car. It is agent-optimized from the Contract programming language, context-rich errors, testability, and more @ccheever shares in his post. You can manage N codebases with Exact - N cars, if you will. However, Exact aims to bring the token cost of building for N platforms down from ~Nx to ~1x, or at least a fraction of ~Nx.
In practice a lot of declarative UI code can be shared in a semantically correct way when the host platforms themselves share similarities. And Exact is built to Use the Platform through and through, except when the platform’s implementations hurt performance too much, in which case Exact uses lower-level native APIs (example: text rendering).
To set expectations, a single-platform Exact codebase does not magically work perfectly on all other platforms. Each requires some platform-specific input to get exactly what you want. However, this first Exact codebase will give your agents a competitive lead to reach a previously ambitious number of platforms.
Finally, agent-optimized code generation with Exact slots into the rest of the Expo agentic infrastructure to help developers achieve autonomously improving apps.
Expo + Exact = self-driving car for application development x.com/ccheever/statu…
In the agentic era every team is empowered to build apps that reach their users everywhere they are. Your agent can write N versions of your app with Exact or anything else for N platforms. When N is a large number of target platforms - and platforms add new intrinsic complexity like iPhone Duo - it is taxing to multiply your token cost by N.
Every company is using agents to build faster on their traditional codebases. They are working on faster horses and, in some cases, N horses.
Exact is the car. It is agent-optimized from the Contract programming language, context-rich errors, testability, and more @ccheever shares in his post. You can manage N codebases with Exact - N cars, if you will. However, Exact aims to bring the token cost of building for N platforms down from ~Nx to ~1x, or at least a fraction of ~Nx.
In practice a lot of declarative UI code can be shared in a semantically correct way when the host platforms themselves share similarities. And Exact is built to Use the Platform through and through, except when the platform’s implementations hurt performance too much, in which case Exact uses lower-level native APIs (example: text rendering).
To set expectations, a single-platform Exact codebase does not magically work perfectly on all other platforms. Each requires some platform-specific input to get exactly what you want. However, this first Exact codebase will give your agents a competitive lead to reach a previously ambitious number of platforms.
Finally, agent-optimized code generation with Exact slots into the rest of the Expo agentic infrastructure to help developers achieve autonomously improving apps.
Expo + Exact = self-driving car for application development x.com/ccheever/statu…
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Charlie Cheever retweeted
Exact (@expo's new framework) works with Argent from day one, zero setup needed 🚀
I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Charlie Cheever retweeted
Wow, one of the best ideas and execution I’ve seen in a while. I’m migrating today to test.
I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Charlie Cheever retweeted
Well, that's impressive. I just built a music player app, it looks super promising and works great with Argent
I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Charlie Cheever retweeted
That app has content before it is finished zooming to fit the screen...
One of the reasons Shopify rewrote their mobile apps from React Native into native was to improve performance metrics like startu p time. Here's the new, optimized, native Shopify Shop app compared to the same thing in Exact. The Exact version is talking to the same GraphQL API ata. (Yes, I'm sure Shopify could make their Swift app as fast to startup with some time and tokens.)
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Charlie Cheever retweeted
Hundreds of millions if not over a billion people depend on apps made with the Expo framework for React Native. It’s worthwhile to make React Native evolutionarily better with some great performance improvements coming in the next version. I also have a swath of commits that create a migration path to better gestures, animations, and native views.
(IMO “React Native vs native” is misled wording - this isn’t directed at you personally, I mean it more generally - and it is more whether the app uses React or doesn’t use React to create native UIs.)
Exact revolutionarily takes the ideas and dreams we’ve had over many years and introduces many changes together, from the programming language to an uncompromising level of quality (esp. on iOS) that is much easier for us to ship in Exact.
As an agentic-era codebase, development of Exact is very AI-forward and the rate of improvement tends to be bottlenecked on our attention, model speeds, and local compute. And since the codebase is owned by Expo we can land all improvements we think will create developer success. Exact should feel like a cohesive solution from one team.
Lastly, Expo’s infrastructure like agentic CI/CD and simulators work with every mobile app today, regardless of framework. We will need to build in support for Exact’s over-the-air updates to Expo Updates in time.
Generally, the cost of rewriting an app is now low enough to fit in a company’s quarterly roadmap and it will only get cheaper, aided with infrastructure like Expo Simulators and languages like Contract.
At Expo we create developer success and that means our infrastructure must accommodate any way a developer chooses to write their app.
(IMO “React Native vs native” is misled wording - this isn’t directed at you personally, I mean it more generally - and it is more whether the app uses React or doesn’t use React to create native UIs.)
Exact revolutionarily takes the ideas and dreams we’ve had over many years and introduces many changes together, from the programming language to an uncompromising level of quality (esp. on iOS) that is much easier for us to ship in Exact.
As an agentic-era codebase, development of Exact is very AI-forward and the rate of improvement tends to be bottlenecked on our attention, model speeds, and local compute. And since the codebase is owned by Expo we can land all improvements we think will create developer success. Exact should feel like a cohesive solution from one team.
Lastly, Expo’s infrastructure like agentic CI/CD and simulators work with every mobile app today, regardless of framework. We will need to build in support for Exact’s over-the-air updates to Expo Updates in time.
Generally, the cost of rewriting an app is now low enough to fit in a company’s quarterly roadmap and it will only get cheaper, aided with infrastructure like Expo Simulators and languages like Contract.
At Expo we create developer success and that means our infrastructure must accommodate any way a developer chooses to write their app.
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Charlie Cheever retweeted
Exact with @e2e_inc agentic end-to-end testing running day one
I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Charlie Cheever retweeted
most UI frameworks pay for a change in proportion to the tree. “Exact ” pays in proportion to the delta.
Contract compiles to bytecode on a Rust runtime, and fine-grained updates write straight into UIKit, AppKit, Android Views and the DOM. there's no full re-render and no tree diff, just the nodes that actually changed.
frameworks used to compete for developer happiness. this one competes on tokens per pixel.
it’s peak !
Contract compiles to bytecode on a Rust runtime, and fine-grained updates write straight into UIKit, AppKit, Android Views and the DOM. there's no full re-render and no tree diff, just the nodes that actually changed.
frameworks used to compete for developer happiness. this one competes on tokens per pixel.
it’s peak !
I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Looking forward to comparing notes with the GeekNative developers
Exact is probably the next chapter of building cross-platform apps!
can't wait to try it out and compare with an approach like GeekNative (geekyants.github.io/geeknative)
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Charlie Cheever retweeted
Rust based, AI native, cross platform framework that outperforms even UIKit itself. Welcome to 2026 everyone 🚀🚀🚀
I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Charlie Cheever retweeted
CROSS-PLATFORM DEVELOPMENT JUST CHANGED 🤯
→ agent-native framework written in Rust 🦀
→ 120fps where SwiftUI drops frames
→ agents can directly control the clock, take screenshots and inspect the UI tree
→ fully open source
⬇️
→ agent-native framework written in Rust 🦀
→ 120fps where SwiftUI drops frames
→ agents can directly control the clock, take screenshots and inspect the UI tree
→ fully open source
⬇️
I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Charlie Cheever retweeted
Exact is the next evolution of cross-platform frameworks. What gets me excited is that it is build on principles that fixes its weaknesses like perf, and the complexity of accessing the underlying platform APIs. My agents love it!
I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Charlie Cheever retweeted
Looks very good and is eerily (or perhaps not) similar to what I think React 20 is shaping up to be. @RyanCarniato's ReactiveScript seems to be converging on something similar, too. x.com/ccheever/statu…
I want to share a preview of something I've been working on called Exact. It's a new Agent Native app framework written in Rust. It's extremely fast and tries to let you build exactly the experience you want with no compromises.
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Charlie Cheever retweeted
Very cool. New Rust framework called Exact.
By the founder of Expo (and Quora)
By the founder of Expo (and Quora)
One of the reasons Shopify rewrote their mobile apps from React Native into native was to improve performance metrics like startu p time. Here's the new, optimized, native Shopify Shop app compared to the same thing in Exact. The Exact version is talking to the same GraphQL API ata. (Yes, I'm sure Shopify could make their Swift app as fast to startup with some time and tokens.)
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Charlie Cheever retweeted
Lots of work.. @ccheever has poured in a number of input tokens that could be measured in potetos, many waking hours, and a fleet of computers and phones on different OSes.
There’s the saying, “If you’re not using a framework, you’re building your own framework.”
In the agentic era, one could add, “If you’re not using someone else’s output tokens, you’re spending your own input tokens.”
The precious output tokens in the form of Exact are open source for everyone.
There’s the saying, “If you’re not using a framework, you’re building your own framework.”
In the agentic era, one could add, “If you’re not using someone else’s output tokens, you’re spending your own input tokens.”
The precious output tokens in the form of Exact are open source for everyone.
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Charlie Cheever retweeted
Contract is a new agent-first programming language for writing high-performance native UIs.
It’s a key part of what makes Exact the agent-native way to write pre-agentic-era native frameworks like UIKit on iOS, AppKit on macOS, SwiftUI on Apple Watch, Android Views & Canvas on Android, the DOM on web, and so on.
Contract is fast to write, fast to deploy, fast to run. The language is designed for agents to write. Deployment is extremely fast with hot reloading and over-the-air updates to get feedback in 10s to 100s of milliseconds. Contract bytecode runs on Rust and uses fine-grained updates to minimize how much of the UI is updated.
As a human metric, an iOS app written with Exact often renders before its window fully expands to fill the screen when the user launches it by tapping its home screen icon, a metric I call “Rendered Before Zoomed”.
Contract is an evolving language. This takes advantage of agents’ tremendous ability to “learn” new programming languages, and the fact that Contract is already fast for agents to write despite its not being in the model weights yet. Contract will become an even more token-efficient way to use native frameworks as models train on it.
It’s a key part of what makes Exact the agent-native way to write pre-agentic-era native frameworks like UIKit on iOS, AppKit on macOS, SwiftUI on Apple Watch, Android Views & Canvas on Android, the DOM on web, and so on.
Contract is fast to write, fast to deploy, fast to run. The language is designed for agents to write. Deployment is extremely fast with hot reloading and over-the-air updates to get feedback in 10s to 100s of milliseconds. Contract bytecode runs on Rust and uses fine-grained updates to minimize how much of the UI is updated.
As a human metric, an iOS app written with Exact often renders before its window fully expands to fill the screen when the user launches it by tapping its home screen icon, a metric I call “Rendered Before Zoomed”.
Contract is an evolving language. This takes advantage of agents’ tremendous ability to “learn” new programming languages, and the fact that Contract is already fast for agents to write despite its not being in the model weights yet. Contract will become an even more token-efficient way to use native frameworks as models train on it.
The way you author UI in Exact is in a new language called Contract. Contract is designed from the ground up for AI agents.
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