diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fe5f3b9..9d73bb3 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -82,6 +82,11 @@ jobs:
       - name: Fix permissions
         run: |
           chmod +x scripts/*.sh
+      
+      - name: Write build info
+        run: |
+          echo "GIT_COMMIT=$(git rev-parse --short HEAD)" > build.txt
+          echo "BUILD_DATE=$(date -u +"%Y-%m-%dT%H:%M:%SZ")" >> build.txt
 
       - name: Upload client Spoolman artifact
         uses: actions/upload-artifact@v3
diff --git a/Dockerfile b/Dockerfile
index f8044c3..7730e65 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -59,6 +59,10 @@ ARG BUILD_DATE=unknown
 ENV GIT_COMMIT=${GIT_COMMIT}
 ENV BUILD_DATE=${BUILD_DATE}
 
+# Write GIT_COMMIT and BUILD_DATE to a build.txt file
+RUN echo "GIT_COMMIT=${GIT_COMMIT}" > build.txt \
+    && echo "BUILD_DATE=${BUILD_DATE}" >> build.txt
+
 # Run command
 EXPOSE 8000
 ENTRYPOINT ["/home/app/spoolman/entrypoint.sh"]
diff --git a/spoolman/env.py b/spoolman/env.py
index 682991a..7fe8c3b 100644
--- a/spoolman/env.py
+++ b/spoolman/env.py
@@ -286,10 +286,16 @@ def get_commit_hash() -> Optional[str]:
     Returns:
         Optional[str]: The commit hash.
     """
-    commit_hash = os.getenv("GIT_COMMIT", "unknown")
-    if commit_hash == "unknown":
+    # Read commit has from build.txt
+    # commit is written as GIT_COMMIT=<hash> in build.txt
+    build_file = Path("build.txt")
+    if not build_file.exists():
         return None
-    return commit_hash
+    with build_file.open(encoding="utf-8") as f:
+        for line in f:
+            if line.startswith("GIT_COMMIT="):
+                return line.split("=")[1].strip()
+    return None
 
 
 def get_build_date() -> Optional[datetime]:
@@ -298,10 +304,16 @@ def get_build_date() -> Optional[datetime]:
     Returns:
         Optional[datetime.datetime]: The build date.
     """
-    build_date = os.getenv("BUILD_DATE", "unknown")
-    if build_date == "unknown":
+    # Read build date has from build.txt
+    # build date is written as BUILD_DATE=<hash> in build.txt
+    build_file = Path("build.txt")
+    if not build_file.exists():
         return None
-    return datetime.fromisoformat(build_date)
+    with build_file.open(encoding="utf-8") as f:
+        for line in f:
+            if line.startswith("BUILD_DATE="):
+                return datetime.fromisoformat(line.split("=")[1].strip())
+    return None
 
 
 def can_write_to_data_dir() -> bool: