diff --git a/src/librustc_codegen_llvm/builder.rs b/src/librustc_codegen_llvm/builder.rs
index 6decc18561444de7323793b134ef3e60e32049d1..289010713395ac34118e984b10aa49281521db55 100644
--- a/src/librustc_codegen_llvm/builder.rs
+++ b/src/librustc_codegen_llvm/builder.rs
@@ -18,7 +18,7 @@
 use rustc::ty::layout::{Align, Size};
 use rustc::session::{config, Session};
 use rustc_data_structures::small_c_str::SmallCStr;
-use interfaces::BuilderMethods;
+use interfaces::{BuilderMethods, Backend};
 use syntax;
 
 use std::borrow::Cow;
@@ -55,11 +55,13 @@ pub struct MemFlags: u8 {
     }
 }
 
-impl BuilderMethods<'a, 'll, 'tcx> for Builder<'a, 'll, 'tcx> {
-    type Value = &'ll Value;
-    type BasicBlock = &'ll BasicBlock;
-    type Type = &'ll type_::Type;
+impl Backend for Builder<'a, 'll, 'tcx>  {
+        type Value = &'ll Value;
+        type BasicBlock = &'ll BasicBlock;
+        type Type = &'ll type_::Type;
+}
 
+impl BuilderMethods<'a, 'll, 'tcx> for Builder<'a, 'll, 'tcx> {
     fn new_block<'b>(
         cx: &'a CodegenCx<'ll, 'tcx>,
         llfn: &'ll Value,
diff --git a/src/librustc_codegen_llvm/interfaces/backend.rs b/src/librustc_codegen_llvm/interfaces/backend.rs
new file mode 100644
index 0000000000000000000000000000000000000000..b2a6bf2dd8c0a5058f9293d290328e651011e858
--- /dev/null
+++ b/src/librustc_codegen_llvm/interfaces/backend.rs
@@ -0,0 +1,15 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub trait Backend {
+    type Value;
+    type BasicBlock;
+    type Type;
+}
diff --git a/src/librustc_codegen_llvm/interfaces/builder.rs b/src/librustc_codegen_llvm/interfaces/builder.rs
index 994ddd65d3df88051aff7c0e61b3e907a72aaa0d..c43e41724eec9f15e1a012748bff86cd7abc1878 100644
--- a/src/librustc_codegen_llvm/interfaces/builder.rs
+++ b/src/librustc_codegen_llvm/interfaces/builder.rs
@@ -14,6 +14,7 @@
 use rustc::ty::layout::{Align, Size};
 use rustc::session::Session;
 use builder::MemFlags;
+use super::backend::Backend;
 
 use std::borrow::Cow;
 use std::ops::Range;
@@ -21,10 +22,7 @@
 
 
 
-pub trait BuilderMethods<'a, 'll :'a, 'tcx: 'll> {
-    type Value;
-    type BasicBlock;
-    type Type;
+pub trait BuilderMethods<'a, 'll :'a, 'tcx: 'll> : Backend {
 
     fn new_block<'b>(
         cx: &'a CodegenCx<'ll, 'tcx, Self::Value>,
diff --git a/src/librustc_codegen_llvm/interfaces/mod.rs b/src/librustc_codegen_llvm/interfaces/mod.rs
index d0cd8e6a696ede82510ffd85596a0116891e1372..b9a356874ba969e5b0294a27b694c1f89e7d87c5 100644
--- a/src/librustc_codegen_llvm/interfaces/mod.rs
+++ b/src/librustc_codegen_llvm/interfaces/mod.rs
@@ -9,5 +9,7 @@
 // except according to those terms.
 
 mod builder;
+mod backend;
 
 pub use self::builder::BuilderMethods;
+pub use self::backend::Backend;