JetBrains ReSharper and Rider 2026.2 EAPs Bring AI Agents to Visual Studio and Up to 100x Faster Branch Switching
Tags AI · Developer Tools · OSS
JetBrains launched the ReSharper 2026.2 EAP introducing Junie AI coding agent integrated into Visual Studio through the Agent Client Protocol (ACP), with an open ACP Agent Registry planned to let developers use any AI agent. Simultaneously, Rider 2026.2 EAP 1 delivered major Roslyn integration performance improvements making branch switching up to 100x faster in worst-case scenarios (8 minutes to 5 seconds), with 2-3x improvements in typical large solutions. The Rider update also includes reworked Unity asmdef reference handling, GDScript improvements, and Azure Functions support migrated into the core IDE.
Technical significance
JetBrains' adoption of the Agent Client Protocol (ACP) and the planned ACP Agent Registry is a direct challenge to Microsoft's vendor lock-in with GitHub Copilot in Visual Studio. By making ReSharper an open AI agent ecosystem, JetBrains is betting that developers want model and agent choice rather than a single integrated solution. The 100x branch switching improvement in Rider addresses one of the most painful daily workflows for .NET developers working in large repositories.