We’re launching Nut.new to help you build complete apps without coding more easily. Existing tools – Bolt, v0, Lovable etc – struggle with fixing non-trivial problems in the code they write. Nut.new uses the Nut API to record your app, analyze its behavior, and explain what is causing the problem. With this explanation, the AI can write a fix more reliably.
Nut.new works similarly to existing tools. Chat with the AI to create the initial app (you can also import an existing project) and continue improving it. When you see a bug in the preview you want fixed, describe it and click the “Fix Bug” button in the prompt. This will create the recording, generate the explanation, and share that explanation with the AI to write a fix.
In the backend the Nut API also uses AI. Using Replay’s Chromium-based browser, Nut records the app and produces what is basically a database of all its behavior, down to the finest detail. The AI can see all of this, and uses a combination of basic techniques (looking at console messages, network requests etc) and advanced techniques (dataflow and control dependency analysis) to get to the underlying cause of problems in the recording.
Nut.new is already pretty good at fixing problems, and we’re working to make it better. We want it to reliably fix anything you’re seeing, as long as it has a clear explanation and the problem isn’t too complicated (AIs aren’t magic). If it’s doing poorly, let us know! Use the UI to leave us some private feedback or save your project to our public set of problems where AIs struggle.
Nut.new is open source and free to use. It is based on Bolt.diy, and like that tool you can add your Anthropic API key and use it as much as you want. We're also offering unlimited free access to Nut.new for early adopters who can give us feedback we'll use to improve Nut. Reach us at hi@replay.io or fill out our contact form to join our early adopter program.