Environment Variables

Overview

You can inject environment variables into a sandbox when creating it. These variables are available to all processes running inside the sandbox, making it easy to pass API keys, configuration values, and other runtime parameters.

Setting Environment Variables

Pass an envVars map (string to string) when creating a sandbox:

const sandbox = await client.createSandbox({
  templateID: "python",
  envVars: {
    OPENAI_API_KEY: "sk-...",
    DATABASE_URL: "postgresql://user:pass@host:5432/db",
    NODE_ENV: "production",
  },
});

curl -X POST https://api.lelantos.ai/sandboxes \
  -H "X-API-Key: lel_your_key_here" \
  -H "Content-Type: application/json" \
  -d '{
    "templateID": "python",
    "envVars": {
      "OPENAI_API_KEY": "sk-...",
      "DATABASE_URL": "postgresql://user:pass@host:5432/db",
      "NODE_ENV": "production"
    }
  }'

Accessing Environment Variables

Inside the sandbox, environment variables are available through the standard OS mechanisms:

# In a shell command
echo $OPENAI_API_KEY

# In Python
import os
api_key = os.environ["OPENAI_API_KEY"]

# In Node.js
const apiKey = process.env.OPENAI_API_KEY;

Best Practices

• Secrets management: Pass API keys and credentials via envVars rather than baking them into templates. This keeps your templates reusable and avoids storing secrets in images.
• Configuration: Use environment variables for any values that change between sandbox instances (endpoints, feature flags, runtime modes).
• Naming: Use UPPER_SNAKE_CASE for environment variable names, following standard convention.