ReSharper has been a staple of .NET development since 2004, well before the current AI wave, as a Visual Studio extension for intelligent code analysis, navigation, and refactoring across C#, VB.NET, XAML, JavaScript, TypeScript, and more. It inspects code continuously, catching errors and code smells before compilation even happens, and offers automated quick-fixes for a huge range of common issues.
Its core feature set, solution-wide refactoring, advanced code cleanup, live inspection, and a smart unit-test runner, has stayed the main reason developers keep it installed for nearly two decades. The newer addition, Junie, brings an LLM-agnostic AI agent into Visual Studio through the Agent Client Protocol, able to refactor code, run terminal commands, manage git operations, and explain legacy code, extending ReSharper's traditional tooling with genuinely agentic capability rather than just smarter autocomplete.
With over 2.5 million downloads, it remains the top-ranked productivity extension on the Visual Studio Marketplace, a position its non-AI refactoring tools earned long before AI coding assistants existed.