# In-Memory Storage Persistent storage of memory messages is often used in development and test environments, and if you use memory-based storage you lose the reliability of local transaction messages. ## Configuration To use in-memory storage, you need to install the following extensions from NuGet: ```powershell PM> Install-Package DotNetCore.CAP.InMemoryStorage ``` Next, add configuration items to the `ConfigureServices` method of `Startup.cs`. ```csharp public void ConfigureServices(IServiceCollection services) { // ... services.AddCap(x => { x.UseInMemoryStorage(); // x.UseXXX ... }); } ``` The successful message in memory, the CAP will be cleaned **every 5 minutes**. ## Publish with transaction In-Memory Storage **Not supported** Transaction mode to send messages.