diff --git a/cmd/authbridge_plugin_sparc.go b/cmd/authbridge_plugin_sparc.go
deleted file mode 100644
index d9acc36..0000000
--- a/cmd/authbridge_plugin_sparc.go
+++ /dev/null
@@ -1,10 +0,0 @@
-//go:build !exclude_plugin_sparc
-
-package cmd
-
-// Registering sparc in the command package (not authlib) mirrors the authbridge
-// binaries: each plugin is a blank import in its own build-tag-excludable file,
-// so a build can drop one with -tags exclude_plugin_sparc without touching code.
-// Without these imports the plugin registry is empty and any config naming a
-// plugin fails with "unknown plugin".
-import _ "github.com/rossoctl/cortex/authbridge/authlib/plugins/sparc"
diff --git a/cmd/authbridge_plugin_sparcplugin.go b/cmd/authbridge_plugin_sparcplugin.go
new file mode 100644
index 0000000..e4bbddd
--- /dev/null
+++ b/cmd/authbridge_plugin_sparcplugin.go
@@ -0,0 +1,22 @@
+//go:build !exclude_plugin_sparc
+
+package cmd
+
+// Registering sparc in the command package (not authlib) mirrors the authbridge
+// binaries: each plugin is a blank import in its own build-tag-excludable file,
+// so a build can drop one with -tags exclude_plugin_sparc without touching code.
+// Without these imports the plugin registry is empty and any config naming a
+// plugin fails with "unknown plugin".
+//
+// The file name ends in "sparcplugin", not "sparc", and must keep doing so.
+// "sparc" is one of the architecture names Go recognizes in the implicit
+// filename constraint, so a file called authbridge_plugin_sparc.go is
+// constrained to GOARCH=sparc and silently dropped everywhere else: it lands in
+// `go list`'s IgnoredGoFiles, this import never runs, and a config naming the
+// plugin fails with `unknown plugin "sparc"` on amd64 and arm64 alike. The
+// build tag above cannot save it, because the file name is applied first. The
+// same suffix is used by cortex's own cmd/authbridge-proxy/plugins_sparcplugin.go.
+//
+// Renaming this file to match its siblings exactly would reintroduce that bug
+// (rossoctl-cli#68), and nothing would fail at build time to say so.
+import _ "github.com/rossoctl/cortex/authbridge/authlib/plugins/sparc"