diff --git a/mylang/repositories.bzl b/mylang/repositories.bzl
index 22bd310..44c2105 100644
--- a/mylang/repositories.bzl
+++ b/mylang/repositories.bzl
@@ -22,17 +22,15 @@ def _mylang_repo_impl(repository_ctx):
         url = url,
         integrity = TOOL_VERSIONS[repository_ctx.attr.mylang_version][repository_ctx.attr.platform],
     )
+    ext = ".exe" if repository_ctx.attr.platform.find("windows") >= 0 else ""
     build_content = """# Generated by mylang/repositories.bzl
 load("@com_myorg_rules_mylang//mylang:toolchain.bzl", "mylang_toolchain")
 
 mylang_toolchain(
     name = "mylang_toolchain",
-    target_tool = select({
-        "@bazel_tools//src/conditions:host_windows": "mylang_tool.exe",
-        "//conditions:default": "mylang_tool",
-    }),
+    target_tool = "mylang_tool{ext}",
 )
-"""
+""".format(ext = ext)
 
     # Base BUILD file for this repository
     repository_ctx.file("BUILD.bazel", build_content)