diff --git a/internal/impl/legacy_extension.go b/internal/impl/message_field_extension.go
similarity index 100%
rename from internal/impl/legacy_extension.go
rename to internal/impl/message_field_extension.go
diff --git a/internal/impl/legacy_unknown.go b/internal/impl/message_field_unknown.go
similarity index 100%
rename from internal/impl/legacy_unknown.go
rename to internal/impl/message_field_unknown.go