As a best-selling author, I invite you to explore my books on Amazon . Don't forget to follow me on Medium and show your support. Thank you! Your support means the world! I’ve spent years writing software, and one thing I’ve learned is that managing dependencies can turn a clean codebase into a tangled mess. Dependency injection (DI) containers help, but most are either too heavy or don’t handle circular dependencies well. I wanted something fast, simple, and safe. So I built my own DI container in Go. Let me walk you through it, piece by piece, like I’m sitting next to you. First, understand the problem. When you have a service that needs a database, and that database needs a config, and the config needs a secret loader, you end up writing a lot of "new" calls. Worse, if two services need each other, you get a circular dependency that crashes your program. I wanted a container that resolves dependencies only when they’re first used – lazy initialization – and catches cycles before they happen.…