Exact
Cross-platform app runtime where AI agents build and test native UIs.
Write an app once in Contract and TypeScript or Rust; run it natively on web, macOS, iOS, and Linux.
Exact is an agent-native cross-platform runtime for developers building apps that run identically on the web, macOS, iOS, and Linux. It suits engineers and coding agents that want a deterministic testing loop without webviews or JavaScript bridges.
What it is
You declare your interface in Contract and write data logic in TypeScript or Rust, which the compiler turns into a compact plan executed by native host renderers. A dedicated agent driver executes ten standard operations like tree, screenshot, tap, and deterministic clock adjustments.
Who it's for
It suits developers building multiplatform apps specifically driven by AI coding agents like Claude Code. It does not suit teams looking for a stable 1.0 release, as it changes daily with no backwards compatibility.
Key features
Agent Native Driver
Ten core operations drive the web, macOS, iOS, and Linux through a single script.
Deterministic Clock Control
Advance the app clock manually between operations to eliminate timing flakes.
No UI JavaScript Bridge
AppKit, UIKit, or GPU painters render the interface directly without webviews.
CSS Layout Kernel
Layout is computed using real CSS rules via a Rust layout kernel.
Up and running in 3 steps
Our honest verdict
What's great
- Runs natively on web, macOS, iOS, and Linux from a single Contract file
- Agent driver supports repeatable test scripts across all supported platforms
- Extremely fast cold starts and edits land in about a tenth of a second
- TypeScript logic compiles to Hermes bytecode at build time
Where it falls short
- Pre-1.0 software that changes daily with no API stability or migration guides
- Requires installing complex toolchains including Rust, Xcode, and Bun
- Design record relies on a separate private repository of numbered documents
Pricing & license
Free under its MIT licence, with no paid hosted option mentioned in the repository. The only cost is running it yourself on your own hardware.
Open remote AI-training roles
880 open remote AI-training roles, updated November 15, 2026; most pay $20–$175 an hour. Zekai lists them free; the application goes to the employer’s platform.
Alternatives
These reviewed AI tools do the same job instantly — from our scored directory.
Use it, or have us set it up
FAQ
Does Exact use a webview for mobile apps?
No, Exact uses native AppKit and UIKit views or GPU painters with no JavaScript bridge in the UI.
How do AI agents test the application?
Agents use a unified script supporting ten deterministic operations including screenshots, taps, typing, and clock manipulation.
Is there backwards compatibility?
No. Exact is pre-1.0 by design with no API stability or migration guides.
