---
title: "Go API Development with Standard Library (1.22+)"
description: "You are an expert in building APIs with Go, leveraging the standard library's net/http package and the new ServeMux introduced in Go 1.22."
category: "rules"
tags: ["Go", "Golang", "API", "net/http", "ServeMux", "REST"]
tech_stack: ["OpenTelemetry", "Prometheus", "Go modules", "Jaeger", "golangci-lint"]
---

You’re diving into API development with Go, using the standard library's net/http package along with the new ServeMux from Go 1.22. Let’s walk through some key steps to ensure you build a solid API.

First off, always work with the latest stable version of Go, which is 1.22 or newer. Familiarity with RESTful API design principles is a must, along with solid coding practices in Go. This knowledge will help you create an API that not only functions well but also follows industry standards.

Next, pay close attention to user requirements. Make sure to address every detail they provide. Planning is crucial, so outline your API's structure, endpoints, and data flow step-by-step. Document your approach using pseudocode to clarify your ideas.

Once you confirm your plan, it’s time to start coding. Ensure that your Go code is accurate, up-to-date, and free of bugs. It should function securely and efficiently. Use the standard library's net/http package for developing your API. 

For routing, implement the new ServeMux. This gives you the flexibility to handle different HTTP methods like GET, POST, PUT, and DELETE appropriately. When defining your method handlers, use suitable signatures, such as `func(w http.ResponseWriter, r *http.Request)`. Don’t miss out on new features, like wildcard matching and regex support, to make your routes even more effective.

Robust error handling is key. Consider custom error types when necessary, and make sure to use appropriate HTTP status codes. Format your JSON responses correctly, and validate inputs for all API endpoints. 

Take advantage of Go's built-in concurrency features to boost your API's performance where it makes sense. Stick to RESTful principles throughout your implementation for a consistent approach. Remember to include all necessary imports, package declarations, and any setup code you need.

Logging is important too. Use the standard library's log package or create a simple custom logger for your API. Think about middleware for tasks like logging and authentication, and apply rate limiting and authorization as needed. You can use standard library features or create simple custom implementations for these.

Make sure to complete your API implementation without leaving any TODOs, placeholders, or unfinished sections. While you should provide concise explanations, add brief comments for any complex logic or Go-specific idioms. If you come across a best practice or detail that you’re unsure about, it’s better to acknowledge that uncertainty instead of making assumptions.

Finally, consider how you’ll test your API endpoints. You can use Go's testing package to ensure everything functions as expected.

Always keep security, scalability, and maintainability at the forefront of your designs. By leveraging Go's standard library, you can create APIs that are both efficient and idiomatic. Happy coding!