freesewing/markdown/dev/reference/api/config/options/const/en.md

---
title: constant
---

If your option is a scalar value (like a string or a number),
it will be treated as a constant. Constant options are never
exposed in the frontend, but can still be set when using FreeSewing
via the API.

## Structure

Any option holding a scalar value is a constant option.

## Example

```js
options: {
  collarFactor: 4.8,
  fitCollar: false,
}
```

<Tip>

##### Why would you use this?

There are typically two use-cases for constant options:

-   Rather than define constants in your code, it's good practice to set
    them in your configuration file.  This way, people who extend your
    pattern can change them if they would like to.
-   A constant option can be used as a feature-flag. Enabling or disabling
    parts of the code beyond the control of the end user, but accessible to
    developers.

</Tip>