diff --git a/adbc_drivers_dev/make.py b/adbc_drivers_dev/make.py
index 3c88019..73c5d03 100644
--- a/adbc_drivers_dev/make.py
+++ b/adbc_drivers_dev/make.py
@@ -229,7 +229,9 @@ def detect_version(
                         )
                     )
             rev = check_output(["git", "rev-parse", "--short", "HEAD"], cwd=repo_root)
-            version += f"-dev.{count}.{rev}"
+            # Prefix the revision so an all-numeric hash with a leading zero is
+            # not interpreted as an invalid numeric SemVer identifier.
+            version += f"-dev.{count}.g{rev}"
 
     # Append -dirty if there are uncommitted changes
     dirty = check_output(["git", "status", "--porcelain"], cwd=repo_root).splitlines()
diff --git a/tests/test_detect_version.py b/tests/test_detect_version.py
index 9611663..f4a3d17 100644
--- a/tests/test_detect_version.py
+++ b/tests/test_detect_version.py
@@ -80,7 +80,7 @@ def test_after_tag(repo):
         cwd=repo,
     )
     version = detect_version(repo)
-    assert version.startswith("v1.2.3-dev.1."), version
+    assert version.startswith("v1.2.3-dev.1.g"), version
 
 
 def test_after_tag_subdir(repo):