diff --git a/crates/fayalite-proc-macros-impl/src/hdl_bundle.rs b/crates/fayalite-proc-macros-impl/src/hdl_bundle.rs
index 09189bd9..538c2da2 100644
--- a/crates/fayalite-proc-macros-impl/src/hdl_bundle.rs
+++ b/crates/fayalite-proc-macros-impl/src/hdl_bundle.rs
@@ -345,6 +345,7 @@ impl ToTokens for Builder {
                     }
                 }));
             quote_spanned! {self.ident.span()=>
+                #[automatically_derived]
                 #[allow(non_camel_case_types, non_snake_case, dead_code)]
                 impl #impl_generics #unfilled_ty
                 #where_clause
diff --git a/crates/fayalite-proc-macros-impl/src/hdl_enum.rs b/crates/fayalite-proc-macros-impl/src/hdl_enum.rs
index 47a5df10..e5cbe277 100644
--- a/crates/fayalite-proc-macros-impl/src/hdl_enum.rs
+++ b/crates/fayalite-proc-macros-impl/src/hdl_enum.rs
@@ -549,6 +549,7 @@ impl ToTokens for ParsedEnum {
         for (index, ParsedVariant { ident, field, .. }) in variants.iter().enumerate() {
             if let Some(ParsedVariantField { ty, .. }) = field {
                 quote_spanned! {span=>
+                    #[automatically_derived]
                     impl #impl_generics #target #type_generics
                     #where_clause
                     {
@@ -570,6 +571,7 @@ impl ToTokens for ParsedEnum {
                             )
                         }
                     }
+                    #[automatically_derived]
                     impl #impl_generics #sim_builder_ident #type_generics
                     #where_clause
                     {
@@ -591,6 +593,7 @@ impl ToTokens for ParsedEnum {
                 }
             } else {
                 quote_spanned! {span=>
+                    #[automatically_derived]
                     impl #impl_generics #target #type_generics
                     #where_clause
                     {
@@ -605,6 +608,7 @@ impl ToTokens for ParsedEnum {
                             )
                         }
                     }
+                    #[automatically_derived]
                     impl #impl_generics #sim_builder_ident #type_generics
                     #where_clause
                     {