Dependency injection is a design pattern that makes coding easier and saves time, especially when working with complex dependencies. Couchbase.Extensions.DependencyInjection is a library that allows developers to use Couchbase clusters and buckets within the ASP.NET Core dependency injection framework. The library provides a simple way to inject Couchbase objects into classes, making it easier to write tests and maintain code. The author of this blog post explores how to set up Couchbase, create a bucket, and use dependency injection with Couchbase.Extensions. They also discuss how to inject complex services and use named buckets, which can simplify the process of injecting dependencies. The library is designed to work with ASP.NET Core 2.2 projects and has been updated to support .NET Core 2.2.