diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 1a12a3e..f3912f0 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -99,8 +99,9 @@ jobs:
       - uses: actions/download-artifact@v4
         with:
           pattern: wheels-*
-          merge-multiple: true
-          path: dist
+          path: wheel-artifacts
+      - name: Merge wheel artifacts
+        run: python3 merge_wheel_artifacts.py wheel-artifacts dist
       - uses: actions/cache/restore@v4
         with:
           key: build-cache-v2-${{ matrix.platform }}-${{ hashFiles('build.sh', 'setup.sh', '*/pyproject.toml', '*/setup.py', '*/build.sh') }}
diff --git a/merge_wheel_artifacts.py b/merge_wheel_artifacts.py
new file mode 100644
index 0000000..aacfb27
--- /dev/null
+++ b/merge_wheel_artifacts.py
@@ -0,0 +1,77 @@
+#!/usr/bin/env python3
+import hashlib
+import pathlib
+import shutil
+import sys
+import zipfile
+
+
+ARTIFACT_PRIORITY = (
+  "wheels-linux-x86_64",
+  "wheels-linux-arm64",
+  "wheels-macos",
+)
+
+
+def wheel_digest(path: pathlib.Path) -> str:
+  h = hashlib.sha256()
+  with path.open("rb") as f:
+    for chunk in iter(lambda: f.read(1024 * 1024), b""):
+      h.update(chunk)
+  return h.hexdigest()
+
+
+def validate_wheel(path: pathlib.Path) -> str:
+  with zipfile.ZipFile(path) as zf:
+    bad_file = zf.testzip()
+  if bad_file is not None:
+    raise RuntimeError(f"{path}: bad zip entry {bad_file}")
+  return wheel_digest(path)
+
+
+def source_priority(artifacts_dir: pathlib.Path, path: pathlib.Path) -> tuple[int, str, str]:
+  source = path.relative_to(artifacts_dir).parts[0]
+  try:
+    index = ARTIFACT_PRIORITY.index(source)
+  except ValueError:
+    index = len(ARTIFACT_PRIORITY)
+  return index, source, str(path)
+
+
+def main() -> int:
+  if len(sys.argv) != 3:
+    print("usage: merge_wheel_artifacts.py <artifacts-dir> <dist-dir>", file=sys.stderr)
+    return 2
+
+  artifacts_dir = pathlib.Path(sys.argv[1])
+  dist_dir = pathlib.Path(sys.argv[2])
+
+  wheels_by_name: dict[str, list[pathlib.Path]] = {}
+  for wheel in artifacts_dir.glob("*/*.whl"):
+    wheels_by_name.setdefault(wheel.name, []).append(wheel)
+
+  if not wheels_by_name:
+    print(f"no wheels found in {artifacts_dir}", file=sys.stderr)
+    return 1
+
+  if dist_dir.exists():
+    shutil.rmtree(dist_dir)
+  dist_dir.mkdir(parents=True)
+
+  for name, wheels in sorted(wheels_by_name.items()):
+    checked = [(source_priority(artifacts_dir, wheel), wheel, validate_wheel(wheel)) for wheel in wheels]
+    checked.sort(key=lambda item: item[0])
+
+    selected = checked[0]
+    if len(checked) > 1:
+      sources = ", ".join(f"{item[0][1]}:{item[2][:12]}" for item in checked)
+      print(f"{name}: duplicate artifact, using {selected[0][1]} ({sources})")
+
+    shutil.copy2(selected[1], dist_dir / name)
+
+  print(f"merged {len(wheels_by_name)} wheels into {dist_dir}")
+  return 0
+
+
+if __name__ == "__main__":
+  sys.exit(main())