What is newt-app?

Newt is a macOS menu bar application for AI-powered text rewriting. The idea is simple: highlight text in any app on your Mac, a document, an email, a Slack message, a code comment, press a keyboard shortcut (Command + semicolon), pick a rewriting prompt from a library, and the selected text is replaced with the rewritten version in place. Because it uses the operating system's standard copy-and-paste layer, it works in any application that supports that, including web apps and desktop tools where other AI writing assistants typically fail. The key design choices are privacy and user control. Newt requires you to provide your own API key from an AI provider such as OpenAI or Anthropic, support for locally-running models is on the roadmap. Your text never leaves your device until you explicitly trigger a rewrite, and only then does it go to whichever provider you chose. There is no telemetry by default. Prompts are stored as plain-text files you can edit, version, and share. The project is built with Rust for the core engine and uses Tauri, a framework for building lightweight desktop applications with a Rust backend and a web-based frontend, for the user interface. The README notes a target footprint of under 20 MB on disk and under 50 MB of memory when idle. The project is currently pre-alpha, with the product specification and visual design locked but code still in active development. It is open source under the Apache 2.0 license.