diff --git a/src/environment.hpp b/src/environment.hpp
index a48839aa7..08452ea32 100644
--- a/src/environment.hpp
+++ b/src/environment.hpp
@@ -112,6 +112,7 @@ namespace Sass {
 
   // define typedef for our use case
   typedef Environment<AST_Node_Obj> Env;
+  typedef std::vector<Env*> EnvStack;
 
 }
 
diff --git a/src/expand.cpp b/src/expand.cpp
index 0e2c22e17..9731d80fa 100644
--- a/src/expand.cpp
+++ b/src/expand.cpp
@@ -24,7 +24,7 @@ namespace Sass {
     in_keyframes(false),
     at_root_without_rule(false),
     old_at_root_without_rule(false),
-    env_stack(std::vector<Env*>()),
+    env_stack(EnvStack()),
     block_stack(BlockStack()),
     call_stack(CallStack()),
     selector_stack(SelectorStack()),
diff --git a/src/expand.hpp b/src/expand.hpp
index 401843b67..1c494194e 100644
--- a/src/expand.hpp
+++ b/src/expand.hpp
@@ -30,7 +30,7 @@ namespace Sass {
     bool              old_at_root_without_rule;
 
     // it's easier to work with vectors
-    std::vector<Env*>              env_stack;
+    EnvStack      env_stack;
     BlockStack    block_stack;
     CallStack     call_stack;
     SelectorStack selector_stack;