env\_vars from the Fastly dashboard and link it to your Compute service. Then, at minimum, add these required key/value pairs:
```bash theme={null}
PROXY_TARGET="https://internal.mysite.io" # The non-edge URL to your website
GROWTHBOOK_API_HOST="https://cdn.growthbook.io"
GROWTHBOOK_CLIENT_KEY="sdk-abc123"
GROWTHBOOK_DECRYPTION_KEY="key_abc123" # Only include for encrypted SDK Connections
```
You may want to further customize the app. Here is a list of common customization variables:
```bash theme={null}
# Disable or change the rendering behavior of Visual Experiments:
# ==========
RUN_VISUAL_EDITOR_EXPERIMENTS="everywhere"|"edge"|"browser"|"skip" # default: "everywhere"
# URL Redirect Experiments are disabled on edge by default. Because the URL does not change, some sites
# may experience problems with loading assets or endpoints with relative paths:
# ==========
RUN_URL_REDIRECT_EXPERIMENTS="everywhere"|"edge"|"browser"|"skip" # default: "browser"
RUN_CROSS_ORIGIN_URL_REDIRECT_EXPERIMENTS="everywhere"|"edge"|"browser"|"skip" # default: "browser"
# Mutate browser URL via window.history.replaceState() to reflect the new URL:
INJECT_REDIRECT_URL_SCRIPT="true" # default "true".
# Do not inject a bootstrapped JavaScript SDK onto the page:
# ==========
DISABLE_INJECTIONS="true" # default "false"
# Customize the edge or injected browser SDK behavior:
# ==========
ENABLE_STREAMING="true" # default "false". Streaming SSE updates on browser.
ENABLE_STICKY_BUCKETING="true" # default "false". Use cookie-based sticky bucketing on edge and browser.
```
#### Runtime configuration
You may want to provide context to your edge app at runtime rather than using environment variables. For example, if you have additional [targeting attributes](/lib/js#attributes) available, you may inject them by modifying your request handler code:
```ts theme={null}
///