# Shopify Functions now support app-owned metafields and reserved prefixes — Shopify developer changelog
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## Shopify Functions now support app-owned metafields and reserved prefixes

You can now use the `$app:` metafield namespace prefix in Shopify Functions [input queries](https://shopify.dev/docs/apps/functions/input-output) to ensure your app's ownership of metafields used in your function.

We recommend use of reserved prefixes by default for all functions, so that you can control access to metafields used by your function. By default, they will be private to your app.

Learn more about [metafield ownership](https://shopify.dev/docs/apps/custom-data/ownership) and [using metafields with input queries](https://shopify.dev/docs/apps/functions/input-output/queries-metafields) on Shopify.dev.

*Published: February 27, 2023*
Tags: API, Update
Link: https://shopify.dev/changelog/shopify-functions-now-support-app-owned-metafields-and-reserved-prefixes

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