Add MODULE.bzl

.bazelci/presubmit.yml

@@ -1,8 +1,5 @@
 ---
 tasks:
-  ubuntu1804:
-    build_targets:
-    - "//..."
   ubuntu2004:
     build_targets:
     - "//..."
@@ -12,3 +9,11 @@ tasks:
   windows:
     build_targets:
     - "//..."
+  ubuntu2004:
+    # No need to check bzlmod on every platform. This repository only holds
+    # constants and has no per-platform behavior.
+    name: check_bzlmod
+    build_targets:
+    - "//..."
+    build_flags:
+    - "--experimental_enable_bzlmod"

MODULE.bazel

@@ -0,0 +1,5 @@
+module(
+    name = "platforms",
+    version = "0.0.6",  # keep in sync with version.bzl
+    compatibility_level = 1,
+)