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This guide walks you through creating your first asterai component and running it in an environment.

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📋 Prerequisites

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Overview

You’ll create a simple component that exports a greeting function, then run it locally in an environment.

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Steps

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1. Install the CLI

npm install -g @asterai/cli

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2. Authenticate

Generate an API key from the console: 
asterai auth login <your_api_key>
Verify you’re logged in: 
asterai auth status

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3. Create a new component

asterai component init hello-world
cd hello-world
This scaffolds a TypeScript component project with the following structure: 
hello-world/
  component.ts       # Component implementation
  component.wit      # WIT interface definition
  package.json       # Build scripts and dependencies
  tsconfig.json
  .gitignore

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4. Understanding the interface

The scaffolded component.wit defines a simple interface. If you’re logged in, the CLI automatically sets your username as the namespace: 
package your-username:hello-world@0.1.0;

interface hello-world {
  greet: func(name: string);
}

world component {
  import asterai:host/api@1.0.0;

  export hello-world;
}
This declares a component that exports one function: greet, which takes a name and prints a greeting.

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5. Understanding the implementation

The scaffolded component.ts implements the interface: 
import * as host from "asterai:host/api@1.0.0";

const greet = (name: string) => {
  console.log(`hello ${name}!`);
};

export const helloWorld = {
  greet
};
The exported object name matches the interface name in component.wit (kebab-case hello-world becomes camelCase helloWorld in TypeScript).

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6. Install dependencies and build

npm install
asterai component build

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7. Push the component

Push your component to the registry: 
asterai component push

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8. Create an environment

Create a new environment and add your component to it: 
asterai env init my-env
asterai env add-component my-env your-username:hello-world@0.1.0

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9. Call your function

Call your component’s function: 
asterai env call my-env your-username:hello-world hello-world.greet '"World"'
You should see: hello World! 🎉

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10. Push to the cloud (optional)

To run your environment in the cloud, push it to the registry: 
asterai env push my-env
Your environment is now available to run on asterai’s cloud infrastructure.

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🎯 What’s Next?

You’ve created a component and run it in an environment. From here you can:
  • ➕ Add more functions to your component
  • 📥 Import other components from the registry
  • 🔧 Add configuration (environment variables, secrets) to your environment
  • 🔗 Compose multiple components in a single environment
See the Components page for more on building components, or Registry for publishing and discovering components.