diff --git a/Dockerfile b/Dockerfile
index ba81de4..97b02c8 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -16,6 +16,7 @@ RUN npm i -g npm@8.10.0
 RUN npm i -g firebase-tools@11.16.0
 
 COPY LICENSE README.md /
+COPY *.env /
 COPY "entrypoint.sh" "/entrypoint.sh"
 
 ENTRYPOINT ["/entrypoint.sh"]
diff --git a/README.md b/README.md
index f7b2ab0..41bf964 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,12 @@ https://firebase.google.com/docs/hosting/github-integration
 
 * `CONFIG_VALUES` - **Optional**. The configuration values for Firebase function that would normally be set with `firebase functions:config:set [value]`. Example: `CONFIG_VALUES: stripe.secret_key=SECRET_KEY zapier.secret_key=SECRET_KEY`.
 
+
+### dotenv
+It's optionally possible to inject the env from an arbitrary `.env`, [as per documentation](https://firebase.google.com/docs/functions/config-env). Useful in particular when the Github Action environment (including secrets) need to be passed on to the Firebase app. 
+
+ATTENTION: It requires a step to copy the needed env inside a `.env.*` or simply `.env` file in the root folder.
+
 ## Example
 
 To authenticate with Firebase, and deploy to Firebase Hosting: