Why Go is the Perfect Language for Building Luminal, My CLI API Testing Tool

As a software engineer, I've always been passionate about creating tools that empower developers and make their workflows more efficient. Over the years, I've worked with various programming languages and frameworks, but one thing has always been clear: the best tools are fast, reliable, and focused. That's why, for my latest project, Luminal—a CLI-based API testing tool—I decided to dive into Go.

Here’s why I’m learning Go for this project and how it aligns with my vision for Luminal.

The Vision Behind Luminal

APIs are the backbone of modern software, and tools like Postman have set the standard for API testing. However, as much as I appreciate Postman's features, I’ve often found myself wanting something leaner, faster, and optimized for the terminal.

Luminal is my attempt to create a terminal-first API testing tool—a lightweight yet powerful alternative to GUI-heavy solutions. It will allow developers to test, organize, and automate their API workflows directly from the command line, with minimal overhead and maximum efficiency.

To achieve these goals, I needed a language that could handle performance, concurrency, and portability while keeping the development process enjoyable. Enter Go.

Why Go?

Here are the key reasons why I chose Go for Luminal:

1. Simplicity Meets Power

Go is renowned for its simplicity. Its clean syntax and minimalistic design make it easy to learn and use, yet it doesn’t compromise on power. For a tool like Luminal, where simplicity and usability are core principles, Go aligns perfectly with the ethos of the project.

2. Blazing Fast Performance

A CLI tool needs to be fast—period. Go's compiled nature ensures that Luminal will execute quickly, even on large collections of API requests or complex workflows. Its low-level control over memory and resources gives me the confidence that performance won’t be a bottleneck.

3. Concurrency Without Pain

API testing often involves sending multiple requests in parallel, simulating real-world scenarios like load testing or workflows dependent on concurrent API calls. Go’s built-in support for concurrency through goroutines and channels makes it an ideal choice for handling such use cases.

4. Portability and Ease of Deployment

Go produces statically linked binaries, which means Luminal will be incredibly easy to distribute. Developers on Linux, macOS, or Windows will be able to download a single binary and start using the tool instantly—no dependencies, no hassle.

5. Strong Ecosystem for CLI Development

Go has a thriving ecosystem of libraries and tools for building command-line applications. Libraries like cobra and urfave/cli provide robust support for building user-friendly CLI interfaces, while Go’s standard library offers excellent support for handling HTTP requests, file I/O, and more.

Learning Go: The Journey So Far

As I’m writing this, I’m currently reading "Powerful Command Line Applications in Go". The book has been a fantastic resource, helping me understand not just the language itself but also best practices for designing and building CLI tools.

Some highlights of my learning journey so far:

• I’ve learned how to structure a CLI application, handle user input, and process flags and commands.
• I’ve explored Go’s standard library for working with HTTP requests and responses—essential for Luminal’s core functionality.
• I’m starting to experiment with workflows, such as chaining multiple API requests together.

What’s Next?

The next steps are to complete the book and start prototyping Luminal’s core features, such as:

• Making HTTP requests with headers, query parameters, and bodies.
• Managing API environments and variables.
• Organizing requests into collections.

Once the basics are in place, I’ll begin integrating more advanced features, like concurrent requests and scripting workflows, to showcase what Go can truly achieve.

Why Share This Journey?

I decided to share my journey for two reasons:

1. Accountability: Documenting my progress helps me stay focused and committed to seeing Luminal through.
2. Inspiration: If you’re a developer considering learning Go or building your own CLI tool, I hope my experience inspires you to take the leap.

Have you tried Go, or are you curious about it? Let me know—I’d love to hear your thoughts or suggestions!

Thanks for reading! 🚀