diff --git a/src/parser.rs b/src/parser.rs
index b4e7bca..3ba7d67 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -5,7 +5,7 @@ use std::convert::identity;
 use convert_case::{Case, Casing};
 use darling::{
     ast::{self, Data},
-    util::{Override, PathList},
+    util::{Flag, Override, PathList},
     Error, FromDeriveInput, FromField, FromMeta,
 };
 use proc_macro2::{Span, TokenStream};
@@ -26,6 +26,7 @@ pub struct ConfigField {
     typ: Option<syn::Type>,
     get: Option<syn::Path>,
     set: Option<syn::Path>,
+    no_serde: Flag,
     #[darling(skip)]
     description: Option<syn::Expr>,
     #[darling(skip)]
@@ -34,7 +35,7 @@ pub struct ConfigField {
 
 impl ConfigField {
     pub(crate) fn needs_newtype(&self) -> bool {
-        self.helper_keys().len() > 1
+        self.helper_keys().len() > 1 || self.typ.is_some()
     }
 
     pub(crate) fn helper(&self, attrs: &[syn::Attribute]) -> (Option<TokenStream>, syn::Type) {
@@ -170,7 +171,10 @@ impl ConfigField {
         })
     }
 
-    pub(crate) fn helper_serde(&self) -> TokenStream {
+    pub(crate) fn helper_serde(&self) -> Option<TokenStream> {
+        if self.no_serde.is_present() {
+            return None;
+        }
         let ident = self.helper_ident();
         let conversion = if self.has_custom_limits() {
             quote! {
@@ -184,7 +188,7 @@ impl ConfigField {
             }
         };
         let ty = &self.ty;
-        quote! {
+        Some(quote! {
             impl ::serde::Serialize for #ident {
                 fn serialize<S>(&self, serializer: S) -> ::core::result::Result::<S::Ok, S::Error>
                 where
@@ -204,7 +208,7 @@ impl ConfigField {
                     #conversion
                 }
             }
-        }
+        })
     }
 
     pub(crate) fn helper_tree(&self) -> TokenStream {
@@ -350,6 +354,13 @@ impl ConfigField {
             .typ
             .as_ref()
             .map_or_else(|| quote!(Self), |typ| quote!(#typ));
+        let match_range = if num_keys > 1 {
+            Some(
+                quote!(1..=#num_keys => ::core::result::Result::Err(::miniconf::Traversal::Access(0, "Cannot write limits").into()),),
+            )
+        } else {
+            None
+        };
         quote! {
             impl<'de> ::miniconf::TreeDeserialize<'de, 1> for #ident {
                 fn deserialize_by_key<K, D>(
@@ -374,8 +385,7 @@ impl ConfigField {
                             #set(<#typ as ::serde::Deserialize>::deserialize(de).map_err(|err| ::miniconf::Error::Inner(0, err))?)?;
                             Ok(0)
                         }
-                        ,
-                        1..=#num_keys => ::core::result::Result::Err(::miniconf::Traversal::Access(0, "Cannot write limits").into()),
+                        #match_range
                         _ => unreachable!(),
                     }
                 }
@@ -391,6 +401,13 @@ impl ConfigField {
         } else {
             quote!(::core::result::Result::Ok(&mut *self))
         };
+        let match_range = if num_keys > 1 {
+            Some(
+                quote!(1..#num_keys => ::core::result::Result::Err(::miniconf::Traversal::Access(1, "cannot return reference to local variable")),),
+            )
+        } else {
+            None
+        };
         quote! {
             impl ::miniconf::TreeAny<1> for #ident {
                 fn ref_any_by_key<K>(&self, mut keys: K) -> ::core::result::Result<&dyn ::core::any::Any, ::miniconf::Traversal>
@@ -406,7 +423,7 @@ impl ConfigField {
                     }
                     match index {
                         0 => ::core::result::Result::Ok(&*self),
-                        1..#num_keys => ::core::result::Result::Err(::miniconf::Traversal::Access(1, "cannot return reference to local variable")),
+                        #match_range
                         _ => unreachable!(),
                     }
                 }
@@ -424,7 +441,7 @@ impl ConfigField {
                     }
                     match index {
                         0 => #ref_mut,
-                        1..#num_keys => ::core::result::Result::Err(::miniconf::Traversal::Access(1, "cannot return reference to local variable")),
+                        #match_range
                         _ => unreachable!(),
                     }
                 }