Add Let's Go book

README.md

@@ -253,6 +253,12 @@ Whether you are planning a new application or working in an existing monolith, t
 
 A book filled with examples on how to use Docker and Go to create the ultimate 12 Factor applications. It goes over individual steps of [The Twelve-Factor App](12factor.net) guidelines and how to implement them with Go and Docker.
 
+### [Let's Go!](https://lets-go.alexedwards.net/)
+
+<img src="https://lets-go.alexedwards.net/sample/assets/img/cover.png" width="120px"/>
+
+Let's Go teaches you step-by-step how to create fast, secure and maintainable web applications using Go. It guides you through the start-to-finish build of a real-world application — covering topics like how to structure your code, manage dependencies, authenticate and authorize users, secure your server and test your application.
+
 Resources
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