litetune fine-tunes a small language model, converts it into a file that runs wherever your app does — phone, desktop, embedded board, robot — and checks that the converted model still does the job.

Converting a model so it fits on a device changes it. The file still loads, the tools still report success, and the model can still be worse at your task than it was before. litetune runs the converted model on data it was never trained on, compares it with the version it came from, and tells you the difference.