diff --git a/.github/workflows/docker.yml b/.github/workflows/docker.yml
index 01781f8..bf7fc06 100644
--- a/.github/workflows/docker.yml
+++ b/.github/workflows/docker.yml
@@ -20,6 +20,11 @@ jobs:
       -
         name: Checkout
         uses: actions/checkout@v3
+      -
+        name: Set environment variables
+        run: |
+          echo "BRANCH=${GITHUB_REF#refs/heads/}" >> $GITHUB_ENV
+          echo "NOW=$(date -R)" >> $GITHUB_ENV # date -Iseconds; date +'%Y-%m-%dT%H:%M:%S'
       -
         name: Set up QEMU
         uses: docker/setup-qemu-action@v2
@@ -29,6 +34,7 @@ jobs:
       -
         name: Login to Docker Hub
         uses: docker/login-action@v2
+        # if: ${{ secrets.DOCKERHUB_USERNAME && secrets.DOCKERHUB_TOKEN }}
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
@@ -44,8 +50,14 @@ jobs:
         uses: docker/build-push-action@v4
         with:
           context: .
-          platforms: linux/amd64,linux/arm64 # ,linux/arm/v7
           push: true
+          build-args: |
+            COMMIT=${{ github.sha }}
+            BRANCH=${{ env.BRANCH }}
+            NOW=${{ env.NOW }}
+          platforms: linux/amd64,linux/arm64 # ,linux/arm/v7
           tags: |
             voglerr/free-games-claimer:latest
             ghcr.io/vogler/free-games-claimer:latest
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
diff --git a/Dockerfile b/Dockerfile
index df20609..67a5e89 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -60,12 +60,19 @@ COPY . .
 RUN dos2unix *.sh && chmod +x *.sh
 COPY docker-entrypoint.sh /usr/local/bin/
 
+ARG COMMIT=""
+ARG BRANCH=""
+ARG NOW=""
+ENV COMMIT=${COMMIT}
+ENV BRANCH=${BRANCH}
+ENV NOW=${NOW}
+
 LABEL org.opencontainers.image.title="free-games-claimer" \
       org.opencontainers.image.name="free-games-claimer" \
       org.opencontainers.image.description="Automatically claims free games on the Epic Games Store, Amazon Prime Gaming and GOG" \
       org.opencontainers.image.url="https://github.com/vogler/free-games-claimer" \
       org.opencontainers.image.source="https://github.com/vogler/free-games-claimer" \
-      org.opencontainers.image.revision=${COMMIT_SHA} \
+      org.opencontainers.image.revision=${COMMIT} \
       org.opencontainers.image.ref.name=${BRANCH} \
       org.opencontainers.image.base.name="ubuntu:jammy" \
       org.opencontainers.image.version="latest"
diff --git a/docker-entrypoint.sh b/docker-entrypoint.sh
index 7796364..2b5ddee 100755
--- a/docker-entrypoint.sh
+++ b/docker-entrypoint.sh
@@ -2,6 +2,10 @@
 
 set -eo pipefail # exit on error, error on any fail in pipe (not just last cmd); add -x to print each cmd; see gist bash_strict_mode.md
 
+echo "Version: https://github.com/vogler/free-games-claimer/tree/${COMMIT}"
+[ ! -z $BRANCH ] && [ $BRANCH != "main" ] && echo "Branch: ${BRANCH}"
+echo "Build: $NOW"
+
 # Remove chromium profile lock.
 # When running in docker and then killing it, on the next run chromium displayed a dialog to unlock the profile which made the script time out.
 # Maybe due to changed hostname of container or due to how the docker container kills playwright - didn't check.
diff --git a/util.js b/util.js
index 8cc91e9..0b2dcbe 100644
--- a/util.js
+++ b/util.js
@@ -108,11 +108,11 @@ export const notify = (html) => new Promise((resolve, reject) => {
   const title = cfg.notify_title ? `-t ${cfg.notify_title}` : '';
   exec(`apprise ${cfg.notify} -i html '${title}' -b '${html}'`, (error, stdout, stderr) => {
     if (error) {
-        console.log(`error: ${error.message}`);
-        if (error.message.includes('command not found')) {
-          console.info('Run `pip install apprise`. See https://github.com/vogler/free-games-claimer#notifications');
-        }
-        return resolve();
+      console.log(`error: ${error.message}`);
+      if (error.message.includes('command not found')) {
+        console.info('Run `pip install apprise`. See https://github.com/vogler/free-games-claimer#notifications');
+      }
+      return resolve();
     }
     if (stderr) console.error(`stderr: ${stderr}`);
     if (stdout) console.log(`stdout: ${stdout}`);
diff --git a/version.js b/version.js
new file mode 100644
index 0000000..7b9ebef
--- /dev/null
+++ b/version.js
@@ -0,0 +1,50 @@
+// check if running the latest version
+
+import {log} from 'console';
+import { readFileSync } from 'fs';
+import { exec } from 'child_process';
+
+const execp = (cmd) => new Promise((resolve, reject) => {
+  exec(cmd, (error, stdout, stderr) => {
+    if (stderr) console.error(`stderr: ${stderr}`);
+    // if (stdout) console.log(`stdout: ${stdout}`);
+    if (error) {
+      console.log(`error: ${error.message}`);
+      if (error.message.includes('command not found')) {
+        console.info('Install git to check for updates!');
+      }
+      return reject();
+    }
+    resolve(stdout.trim());
+  });
+});
+
+const git_main = () => readFileSync('.git/refs/heads/main').toString().trim();
+
+let sha, date;
+// if (existsSync('/.dockerenv')) { // did not work
+if (process.env.NOVNC_PORT) {
+  log('Running inside Docker.');
+  ['COMMIT', 'BRANCH', 'NOW'].forEach(v => log(`  ${v}:`, process.env[v]));
+  sha = process.env.COMMIT;
+  date = process.env.NOW;
+} else {
+  log('Not running inside Docker.');
+  sha = await execp('git rev-parse HEAD');
+  date = await execp('git show -s --format=%cD'); // same as format as `date -R` (RFC2822)
+  // date = await execp('git show -s --format=%ch'); // %ch is same as --date=human (short/relative)
+}
+
+const gh = await (await fetch('https://api.github.com/repos/vogler/free-games-claimer/commits/main', {
+    // headers: { accept: 'application/vnd.github.VERSION.sha' }
+  })).json();
+// log(gh);
+
+log('Local commit:', sha, new Date(date));
+log('Online commit:', gh.sha, new Date(gh.commit.committer.date));
+
+if (sha == gh.sha) {
+  log('Running the latest version!')
+} else {
+  log('Not running the latest version!')
+}