Hello World

Let’s write a simple program that uses AI to translate “Hello World” into multiple languages.

Create Your First Program

Create a file called hello.vibe:

model translator = {
  name: "claude-haiku-4-5-20251001",
  provider: "anthropic",
  apiKey: env("ANTHROPIC_API_KEY")
}

const languages: text[] = do "List the major human languages"

for language in languages {
  const translated = do "Translate 'Hello World' into {language}"
  print(translated)
}

Run It

vibe hello.vibe

You’ll see “Hello World” translated into various languages!

Understanding the Code

Let’s break down what’s happening:

Model Declaration

model translator = {
  name: "claude-haiku-4-5-20251001",
  provider: "anthropic",
  apiKey: env("ANTHROPIC_API_KEY")
}

This configures which AI model to use. The env() function reads from your environment variables.

AI Expression with do

const languages: text[] = do "List the major human languages"

The do keyword sends a prompt to the AI and returns the result. Here we’re asking for a list of languages and typing it as text[] (array of strings).

Loop with Context

for language in languages {
  const translated = do "Translate 'Hello World' into {language}"
  print(translated)
}

The {language} syntax creates a reference that the AI can see in context. The AI knows what language contains and uses it to complete the task. See AI Prompts for more on interpolation.

Try Different Providers

Switch to OpenAI by changing the model:

model translator = {
  name: "gpt-5.2",
  provider: "openai",
  apiKey: env("OPENAI_API_KEY")
}

Or Google:

model translator = {
  name: "gemini-3-flash",
  provider: "google",
  apiKey: env("GOOGLE_API_KEY")
}

Next Steps

Now that you’ve written your first program, learn about:

• Basic Syntax - Variables, types, and operators
• AI Prompts - The do and vibe keywords in depth
• Models - Configuring AI providers