diff --git a/docker-compose.yml b/docker-compose.yml
index 0fe4cc3..80738c2 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -1,6 +1,9 @@
 services:
   web:
-    build: ./web
+    build:
+      context: ./web
+      args:
+        SOURCE_COMMIT: ${SOURCE_COMMIT:-dev}
     container_name: lazyflat-web
     restart: unless-stopped
     depends_on:
diff --git a/web/Dockerfile b/web/Dockerfile
index ac31eb5..ba5000c 100644
--- a/web/Dockerfile
+++ b/web/Dockerfile
@@ -8,6 +8,13 @@ RUN pip install --no-cache-dir -r requirements.txt
 
 COPY . .
 
+# Stamp the image with the git SHA so the web footer can show which commit is
+# live. Coolify passes SOURCE_COMMIT as a build arg on every deploy; outside
+# Coolify the ARG defaults to "dev". Placed after COPY so only this thin layer
+# rebuilds when the SHA changes — pip install stays cached.
+ARG SOURCE_COMMIT=dev
+ENV GIT_COMMIT=${SOURCE_COMMIT}
+
 EXPOSE 8000
 
 HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
diff --git a/web/common.py b/web/common.py
index d8a89f3..35d7e39 100644
--- a/web/common.py
+++ b/web/common.py
@@ -23,7 +23,7 @@ import db
 import notifications
 from apply_client import ApplyClient, _row_to_profile
 from auth import issue_csrf_token
-from settings import APPLY_FAILURE_THRESHOLD, INTERNAL_API_KEY
+from settings import APPLY_FAILURE_THRESHOLD, GIT_COMMIT, INTERNAL_API_KEY
 
 
 logger = logging.getLogger("web")
@@ -114,6 +114,8 @@ def base_context(request: Request, user, active_tab: str) -> dict:
         "csrf": issue_csrf_token(user["id"]),
         "active_tab": active_tab,
         "is_admin": bool(user["is_admin"]),
+        "git_commit": GIT_COMMIT,
+        "git_commit_short": GIT_COMMIT[:7] if GIT_COMMIT and GIT_COMMIT != "dev" else GIT_COMMIT,
     }
 
 
diff --git a/web/settings.py b/web/settings.py
index 5df1d2e..6c3db0c 100644
--- a/web/settings.py
+++ b/web/settings.py
@@ -59,3 +59,8 @@ PUBLIC_URL: str = getenv("PUBLIC_URL", "https://flat.lab.moritz.run")
 # --- LLM enrichment (Anthropic Haiku) -----------------------------------------
 ANTHROPIC_API_KEY: str = getenv("ANTHROPIC_API_KEY", "")
 ANTHROPIC_MODEL: str = getenv("ANTHROPIC_MODEL", "claude-haiku-4-5-20251001")
+
+# --- Build info --------------------------------------------------------------
+# Baked into the image at docker build time via the Dockerfile ARG; rendered in
+# the site footer so the running commit is visible at a glance.
+GIT_COMMIT: str = getenv("GIT_COMMIT", "dev")
diff --git a/web/templates/_layout.html b/web/templates/_layout.html
index 418414f..f93a029 100644
--- a/web/templates/_layout.html
+++ b/web/templates/_layout.html
@@ -31,5 +31,9 @@
 </main>
 <footer class="text-center text-xs text-slate-500 py-6">
     Mit ♥ programmiert für Annika
+    {% if git_commit_short %}
+    <span class="mx-1">·</span>
+    <span title="{{ git_commit }}">build {{ git_commit_short }}</span>
+    {% endif %}
 </footer>
 {% endblock %}