diff --git a/rust/rust.go b/rust/rust.go
index 61b51e5..4f5e7fb 100644
--- a/rust/rust.go
+++ b/rust/rust.go
@@ -496,7 +496,7 @@
 	}
 
 	// proc_macros are compiler plugins, and so we need the host arch variant as a dependendcy.
-	actx.AddFarVariationDependencies([]blueprint.Variation{{Mutator: "arch", Variation: ctx.Config().BuildOsVariant}}, procMacroDepTag, deps.ProcMacros...)
+	actx.AddFarVariationDependencies(ctx.Config().BuildOSTarget.Variations(), procMacroDepTag, deps.ProcMacros...)
 }
 
 func (mod *Module) Name() string {