The Lightweight Test Automation Framework (LTAF) for ASP.NET is an open source project that was developed and is currently used by the ASP.NET QA Team to automate regression tests for the product. It is designed to run within an ASP.NET application.

Tests can be written in any .NET Framework language. Tests use an API to manipulate and verify the DOM of the browser. The Lightweight Test Automation Framework supports running tests in Microsoft Internet Explorer, Mozilla Firefox, Apple Safari, and Opera. In addition, LTAF provides an emulated UI-less version of the browser, that simplifies scenarios when LTAF tests live in some larger automated tests projects, unit tests for example.