Hello world

Your first Fluxzero handler

Let’s make sure everything’s working.

In this mini-tutorial we’re going to create the simplest possible Fluxzero app — just a single HTTP endpoint.

Note

Ask your coding agent to make each change. The explanations below help you understand the code and what the application does.

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1. Create a project

If you haven’t created a project yet, follow the installation guide first.

Have your coding agent open the project. IntelliJ IDEA ↗ provides a good Java and Kotlin experience whenever you want to inspect or edit the code directly.

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2. Add an endpoint

Ask your agent to create a file named HelloEndpoint.java (or .kt) in the root package:

Java

@Component
public class HelloEndpoint {

    @HandleGet("/hello")
    public String hello() {
        return "Hello from Fluxzero!";
    }
}

Kotlin

@Component
class HelloEndpoint {

    @HandleGet("/hello")
    fun hello(): String {
        return "Hello from Fluxzero!"
    }
}

Tip

You can define HTTP handlers in any app — no routing config or proxies required.

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3. Run your app

Start the app:

./gradlew run

Then open your browser:

http://localhost:8080/hello

You should see:

Hello from Fluxzero!

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4. What’s next?

You’ve just added your first Fluxzero handler!

Now that your app is up and running, let’s build something real.