---
description: Variables and secrets are bound as follows:
title: Variables and Secrets
image: https://developers.cloudflare.com/og-docs.png
---

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# Variables and Secrets

Last updated Aug 24, 2026|Copy as Markdown|[View as Markdown](https://e8aee267.previews.developers.cloudflare.com/workers/testing/miniflare/core/variables-secrets/index.md)|[Agent setup](https://e8aee267.previews.developers.cloudflare.com/agent-setup/)

## Bindings

Variables and secrets are bound as follows:

```js
const mf = new Miniflare({
	bindings: {
		KEY1: "value1",
		KEY2: "value2",
	},
});
```

## Text and Data Blobs

Text and data blobs can be loaded from files. File contents will be read and bound as `string`s and `ArrayBuffer`s respectively.

```js
const mf = new Miniflare({
	textBlobBindings: { TEXT: "text.txt" },
	dataBlobBindings: { DATA: "data.bin" },
});
```

## Globals

Injecting arbitrary globals is not supported by [workerd ↗](https://github.com/cloudflare/workerd). If you're using a service Worker, bindings will be injected as globals, but these must be JSON-serializable.

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