diff --git a/buf/plugin.toml b/buf/plugin.toml
index 9ba58ef..87962e5 100644
--- a/buf/plugin.toml
+++ b/buf/plugin.toml
@@ -4,12 +4,8 @@ type = "cli"
 [resolve]
 git-url = "https://github.com/bufbuild/buf"
 
-# buf names macOS arm assets "arm64". Linux arm assets are "aarch64", but the CI
-# matrix has no Linux arm target, so aarch64 only ever resolves on macOS here.
-[install.arch]
-aarch64 = "arm64"
-x86_64 = "x86_64"
-
+# buf spells the arm architecture per OS: Linux assets say "aarch64", Darwin and
+# Windows ones say "arm64", so the rename lives on those two platforms only.
 [platform.linux]
 download-file = "buf-Linux-{arch}.tar.gz"
 checksum-file = "sha256.txt"
@@ -20,11 +16,17 @@ download-file = "buf-Darwin-{arch}.tar.gz"
 checksum-file = "sha256.txt"
 exe-path = "buf/bin/buf"
 
+[platform.macos.arch]
+aarch64 = "arm64"
+
 [platform.windows]
 download-file = "buf-Windows-{arch}.zip"
 checksum-file = "sha256.txt"
 exe-path = "buf/bin/buf.exe"
 
+[platform.windows.arch]
+aarch64 = "arm64"
+
 [install]
 download-url = "https://github.com/bufbuild/buf/releases/download/v{version}/{download_file}"
 checksum-url = "https://github.com/bufbuild/buf/releases/download/v{version}/{checksum_file}"