Modus provides a local development environment that makes it easy to build and test your app, with local access to models.

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Launching your app in development mode

To run your app, from the project root, run: 
modus dev
The modus dev command compiles your app code, starts a local server, and provides a URL to access your app’s API. It also enables fast refresh, which automatically recompiles and reloads any changed functions while preserving app state during development. Once your app is running, you can access the graphical interface for your API at the URL located in your terminal. 
View endpoint: http://localhost:8686/explorer
The API Explorer interface allows you to interact with your app’s API and test your functions. API Graphical Interface.

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Environment secrets

When you run your app locally using modus dev, the runtime replaces the placeholders of the manifest with values from environment variables defined in your operating system or in .env files. The environment variables keys must be upper case and follow the naming convention: MODUS_<CONNECTION NAME>_<PLACEHOLDER> For example, with the following manifest:
modus.json
{
  "connections": {
    "openai": {
      "type": "http",
      "baseUrl": "https://api.openai.com/",
      "headers": {
        "Authorization": "Bearer {{API_KEY}}"
      }
    }
  }
}
The Modus runtime substitutes {{API_KEY}} with the value of the environment variable MODUS_OPENAI_API_KEY An easy way to define the environment variables when working locally is to use the file .env.dev.local located in your app folder. For the previous manifest, we can set the key in the .env.dev.local file as follow:
.env.dev.local
MODUS_OPENAI_API_KEY="your openai key"
You should exclude .env files from source control. Projects created with modus new exclude these files automatically when creating your project.

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Using Hypermode-hosted models

To use Hypermode-hosted models in your local environment, first install the Hyp CLI: 
npm install -g @hypermode/hyp-cli
Then log in to your Hypermode account: 
hyp login
After logging in, your app automatically connects to Hypermode’s Model Router when running locally.