diff --git a/setup.py b/setup.py
index 8e4aad6..48272c6 100644
--- a/setup.py
+++ b/setup.py
@@ -108,6 +108,16 @@ def ensure_local_folder() -> None:
     pkg_resources.ensure_directory(bin_path)
 
 
+PLATFORM_MAP = {
+    "win32": "win32",
+    "win64": "win64",
+    "linux32": "linux32",
+    "linux64": "linux64",
+    "darwin64": "macos",
+    "darwin32": "macos",  # This is impossible (?)
+}
+
+
 def assemble_driver_uri(
     version: T.Optional[str] = None, platform: T.Optional[str] = None
 ) -> str:
@@ -129,7 +139,7 @@ def assemble_driver_uri(
     else:
         ext = "tar.gz"
     return "{base}/releases/download/{vers}/geckodriver-{vers}-{platform}.{ext}".format(
-        base=GECKO_RELEASE_PATH, vers=version, platform=platform, ext=ext
+        base=GECKO_RELEASE_PATH, vers=version, platform=PLATFORM_MAP[platform], ext=ext
     )