diff --git a/include/sparrow/buffer.hpp b/include/sparrow/buffer.hpp
index 053853ff..fc8f6bb0 100644
--- a/include/sparrow/buffer.hpp
+++ b/include/sparrow/buffer.hpp
@@ -128,7 +128,10 @@ namespace sparrow
 
         template <class A>
         requires (not std::same_as<A, buffer<T>> and allocator<A>)
-        constexpr explicit buffer(const A& a);
+        constexpr explicit buffer(const A& a) 
+            : base_type(a)
+        {
+        }
 
         template <allocator A = allocator_type>
         explicit buffer(size_type n, const A& a = A());
@@ -374,14 +377,6 @@ namespace sparrow
      * buffer implementation *
      *************************/
 
-    template <class T>
-    template <class A>
-    requires (not std::same_as<A, buffer<T>> and allocator<A>)
-    constexpr buffer<T>::buffer(const A& a)
-        : base_type(a)
-    {
-    }
-
     template <class T>
     template <allocator A>
     buffer<T>::buffer(size_type n, const A& a)