diff --git a/ipc/codegen/src/codegen.rs b/ipc/codegen/src/codegen.rs
index f56e00430..a2fa0ee49 100644
--- a/ipc/codegen/src/codegen.rs
+++ b/ipc/codegen/src/codegen.rs
@@ -28,6 +28,7 @@ use syntax::ast::{
 	TraitRef,
 	Ident,
 	Generics,
+	TraitItemKind,
 };
 
 use syntax::ast;
@@ -80,19 +81,23 @@ pub fn replace_slice_u8(builder: &aster::AstBuilder, ty: &P<ast::Ty>) -> P<ast::
 	ty.clone()
 }
 
+struct NamedSignature<'a> {
+	sig: &'a MethodSig,
+	ident: &'a Ident,
+}
+
 fn push_invoke_signature_aster(
 	builder: &aster::AstBuilder,
-	implement: &ImplItem,
-	signature: &MethodSig,
+	named_signature: &NamedSignature,
 	push: &mut FnMut(Annotatable),
 ) -> Dispatch {
-	let inputs = &signature.decl.inputs;
+	let inputs = &named_signature.sig.decl.inputs;
 	let (input_type_name, input_arg_names, input_arg_tys) = if inputs.len() > 0 {
 		let first_field_name = field_name(builder, &inputs[0]).name.as_str();
 		if first_field_name == "self" && inputs.len() == 1 { (None, vec![], vec![]) }
 		else {
 			let skip = if first_field_name == "self" { 2 } else { 1 };
-			let name_str = format!("{}_input", implement.ident.name.as_str());
+			let name_str = format!("{}_input", named_signature.ident.name.as_str());
 
 			let mut arg_names = Vec::new();
 			let mut arg_tys = Vec::new();
@@ -126,9 +131,9 @@ fn push_invoke_signature_aster(
 		(None, vec![], vec![])
 	};
 
-	let return_type_ty = match signature.decl.output {
+	let return_type_ty = match named_signature.sig.decl.output {
 		FunctionRetTy::Ty(ref ty) => {
-			let name_str = format!("{}_output", implement.ident.name.as_str());
+			let name_str = format!("{}_output", named_signature.ident.name.as_str());
 			let tree = builder.item()
 				.attr().word("derive(Binary)")
 				.attr().word("allow(non_camel_case_types)")
@@ -141,7 +146,7 @@ fn push_invoke_signature_aster(
 	};
 
 	Dispatch {
-		function_name: format!("{}", implement.ident.name.as_str()),
+		function_name: format!("{}", named_signature.ident.name.as_str()),
 		input_type_name: input_type_name,
 		input_arg_names: input_arg_names,
 		input_arg_tys: input_arg_tys,
@@ -587,8 +592,8 @@ fn push_client_implementation(
 	let handshake_item = quote_impl_item!(cx,
 		pub fn handshake(&self) -> Result<(), ::ipc::Error> {
 			let payload = ::ipc::Handshake {
-				protocol_version: Arc::<$endpoint>::protocol_version(),
-				api_version: Arc::<$endpoint>::api_version(),
+				protocol_version: ::std::sync::Arc::<$endpoint>::protocol_version(),
+				api_version: ::std::sync::Arc::<$endpoint>::api_version(),
 			};
 
 			::ipc::invoke(
@@ -771,8 +776,43 @@ fn implement_interface(
 	item: &Item,
 	push: &mut FnMut(Annotatable),
 ) -> Result<InterfaceMap, Error> {
-	let (generics, impl_trait, original_ty, impl_items) = match item.node {
-		ast::ItemKind::Impl(_, _, ref generics, ref impl_trait, ref ty, ref impl_items) => (generics, impl_trait, ty, impl_items),
+	let (generics, impl_trait, original_ty, dispatch_table) = match item.node {
+		ast::ItemKind::Impl(_, _, ref generics, ref impl_trait, ref ty, ref impl_items) => {
+			let mut method_signatures = Vec::new();
+			for impl_item in impl_items {
+				if let ImplItemKind::Method(ref signature, _) = impl_item.node {
+					method_signatures.push(NamedSignature { ident: &impl_item.ident, sig: signature });
+				}
+			}
+
+			let dispatch_table = method_signatures.iter().map(|named_signature|
+				push_invoke_signature_aster(builder, named_signature, push))
+			.collect::<Vec<Dispatch>>();
+
+			(generics, impl_trait.clone(), ty.clone(), dispatch_table)
+		},
+		ast::ItemKind::Trait(_, ref generics, _, ref trait_items) => {
+			let mut method_signatures = Vec::new();
+			for trait_item  in trait_items {
+				if let TraitItemKind::Method(ref signature, _) = trait_item.node {
+					method_signatures.push(NamedSignature { ident: &trait_item.ident, sig: signature });
+				}
+			}
+
+			let dispatch_table = method_signatures.iter().map(|named_signature|
+				push_invoke_signature_aster(builder, named_signature, push))
+			.collect::<Vec<Dispatch>>();
+
+			(
+				generics,
+				Some(ast::TraitRef {
+					path: builder.path().ids(&[item.ident.name]).build(),
+					ref_id: item.id,
+				}),
+				builder.ty().id(item.ident),
+				dispatch_table
+			)
+		},
 		_ => {
 			cx.span_err(
 				item.span,
@@ -783,30 +823,19 @@ fn implement_interface(
 	let impl_generics = builder.from_generics(generics.clone()).build();
 	let where_clause = &impl_generics.where_clause;
 
-	let mut method_signatures = Vec::new();
-	for impl_item in impl_items {
-		if let ImplItemKind::Method(ref signature, _) = impl_item.node {
-			method_signatures.push((impl_item, signature))
-		}
-	}
-
-	let dispatch_table = method_signatures.iter().map(|&(impl_item, signature)|
-			push_invoke_signature_aster(builder, impl_item, signature, push))
-		.collect::<Vec<Dispatch>>();
-
 	let dispatch_arms = implement_dispatch_arms(cx, builder, &dispatch_table, false);
 	let dispatch_arms_buffered = implement_dispatch_arms(cx, builder, &dispatch_table, true);
 
 	let (handshake_arm, handshake_arm_buf) = implement_handshake_arm(cx);
 
 	let ty = ty_ident_map(&original_ty).ident(builder);
-	let interface_endpoint = match *impl_trait {
-		Some(ref trait_) => builder.id(::syntax::print::pprust::path_to_string(&trait_.path)),
-		None => ty
+	let (interface_endpoint, host_generics) = match impl_trait {
+		Some(ref trait_) => (builder.id(::syntax::print::pprust::path_to_string(&trait_.path)), None),
+		None => (ty, Some(&impl_generics)),
 	};
 
 	let ipc_item = quote_item!(cx,
-		impl $impl_generics ::ipc::IpcInterface<$interface_endpoint> for Arc<$interface_endpoint> $where_clause {
+		impl $host_generics ::ipc::IpcInterface<$interface_endpoint> for ::std::sync::Arc<$interface_endpoint> $where_clause {
 			fn dispatch<R>(&self, r: &mut R) -> Vec<u8>
 				where R: ::std::io::Read
 			{
diff --git a/ipc/tests/examples.rs b/ipc/tests/examples.rs
index 8b52be11c..7afcd583d 100644
--- a/ipc/tests/examples.rs
+++ b/ipc/tests/examples.rs
@@ -19,10 +19,11 @@ mod tests {
 
 	use super::super::service::*;
 	use super::super::binary::*;
-	use super::super::nested::{DBClient,DBWriter};
+	use super::super::nested::{DBClient, DBWriter};
 	use ipc::*;
 	use devtools::*;
 	use semver::Version;
+	use std::sync::Arc;
 
 	#[test]
 	fn call_service() {
@@ -33,7 +34,7 @@ mod tests {
 			4, 0, 0, 0, 0, 0, 0, 0,
 			10, 0, 0, 0]);
 
-		let service = Service::new();
+		let service = Arc::new(Service::new());
 		assert_eq!(0, *service.commits.read().unwrap());
 
 		service.dispatch(&mut socket);
@@ -65,7 +66,7 @@ mod tests {
 				0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 			]);
 
-		let service = Service::new();
+		let service = Arc::new(Service::new());
 		let result = service.dispatch(&mut socket);
 
 		// single `true`
@@ -109,9 +110,9 @@ mod tests {
 
 	#[test]
 	fn query_default_version() {
-		let ver = Service::protocol_version();
+		let ver = Arc::<Service>::protocol_version();
 		assert_eq!(ver, Version::parse("1.0.0").unwrap());
-		let ver = Service::api_version();
+		let ver = Arc::<Service>::api_version();
 		assert_eq!(ver, Version::parse("1.0.0").unwrap());
 	}
 
diff --git a/ipc/tests/nested.rs.in b/ipc/tests/nested.rs.in
index 26f344d92..c249799f2 100644
--- a/ipc/tests/nested.rs.in
+++ b/ipc/tests/nested.rs.in
@@ -33,7 +33,7 @@ pub trait DBWriter {
 	fn write_slice(&self, data: &[u8]) -> Result<(), DBError>;
 }
 
-impl<L: Sized> IpcConfig for DB<L> {}
+impl IpcConfig<DBWriter> for ::std::sync::Arc<DBWriter> {}
 
 #[derive(Binary)]
 pub enum DBError { Write, Read }
@@ -53,3 +53,9 @@ impl<L: Sized> DBWriter for DB<L> {
 	}
 }
 
+#[derive(Ipc)]
+trait DBNotify {
+	fn notify(&self, a: u64, b: u64) -> bool;
+}
+
+impl IpcConfig<DBNotify> for ::std::sync::Arc<DBNotify> { }
diff --git a/ipc/tests/service.rs.in b/ipc/tests/service.rs.in
index 6bee63133..1e3d235e5 100644
--- a/ipc/tests/service.rs.in
+++ b/ipc/tests/service.rs.in
@@ -70,4 +70,4 @@ impl Service {
 	}
 }
 
-impl ::ipc::IpcConfig for Service {}
+impl ::ipc::IpcConfig<Service> for ::std::sync::Arc<Service> {}
diff --git a/ipc/tests/with_attrs.rs.in b/ipc/tests/with_attrs.rs.in
index 0168f3a72..8458667ef 100644
--- a/ipc/tests/with_attrs.rs.in
+++ b/ipc/tests/with_attrs.rs.in
@@ -31,4 +31,4 @@ impl BadlyNamedService {
 	}
 }
 
-impl ::ipc::IpcConfig for BadlyNamedService {}
+impl ::ipc::IpcConfig<BadlyNamedService> for ::std::sync::Arc<BadlyNamedService> {}