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StoryQ is a portable (single dll), embedded BDD framework for .NET 3.5. It runs within your existing test runner and helps produce human-friendly test output (html or text). StoryQ's fluent interface adds strong typing, intellisense and documentation to your BDD grammar.

When you make a unit test assertion with PowerAssert, your assertion messages become much more useful.

SpecLight is an internal DSL for BDD testing in C#.