diff --git a/beast/nudb/api.h b/beast/nudb/api.h
index 65ad74919..4891b364f 100644
--- a/beast/nudb/api.h
+++ b/beast/nudb/api.h
@@ -21,6 +21,7 @@
 #define BEAST_NUDB_API_H_INCLUDED
 
 #include <beast/nudb/create.h>
+#include <beast/nudb/identity.h>
 #include <beast/nudb/store.h>
 #include <beast/nudb/recover.h>
 #include <beast/nudb/verify.h>
@@ -34,7 +35,7 @@ namespace nudb {
 //
 template <
     class Hasher,
-    class Codec,
+    class Codec = identity,
     class File = native_file,
     std::size_t BufferSize = 16 * 1024 * 1024
 >
diff --git a/beast/nudb/identity_codec.h b/beast/nudb/identity.h
similarity index 97%
rename from beast/nudb/identity_codec.h
rename to beast/nudb/identity.h
index 0846e3002..18b3dcad8 100644
--- a/beast/nudb/identity_codec.h
+++ b/beast/nudb/identity.h
@@ -26,12 +26,12 @@ namespace beast {
 namespace nudb {
 
 /** Codec which maps input directly to output. */
-class identity_codec
+class identity
 {
 public:
     template <class... Args>
     explicit
-    identity_codec(Args&&... args)
+    identity(Args&&... args)
     {
     }
 
diff --git a/beast/nudb/store.h b/beast/nudb/store.h
index 49b4abbb1..e06c00828 100644
--- a/beast/nudb/store.h
+++ b/beast/nudb/store.h
@@ -372,7 +372,7 @@ store<Hasher, Codec, File>::open (
     key_file_header kh;
     read (df, dh);
     read (kf, kh);
-    verify<Codec> (dh);
+    verify (dh);
     verify<Hasher> (kh);
     verify<Hasher> (dh, kh);
     auto s = std::make_unique<state>(
diff --git a/beast/nudb/tests/common.h b/beast/nudb/tests/common.h
index 82c6e5143..4f7e456f2 100644
--- a/beast/nudb/tests/common.h
+++ b/beast/nudb/tests/common.h
@@ -21,7 +21,7 @@
 #define BEAST_NUDB_TESTS_COMMON_H_INCLUDED
 
 #include <beast/nudb.h>
-#include <beast/nudb/identity_codec.h>
+#include <beast/nudb/identity.h>
 #include <beast/nudb/tests/fail_file.h>
 #include <beast/hash/xxhasher.h>
 #include <beast/random/xor_shift_engine.h>
@@ -37,7 +37,7 @@ using key_type = std::size_t;
 
 // xxhasher is fast and produces good results
 using test_api_base =
-    nudb::api<xxhasher, identity_codec, native_file>;
+    nudb::api<xxhasher, identity, native_file>;
 
 struct test_api : test_api_base
 {
diff --git a/beast/nudb/visit.h b/beast/nudb/visit.h
index d0167b5fd..9243101f6 100644
--- a/beast/nudb/visit.h
+++ b/beast/nudb/visit.h
@@ -56,7 +56,7 @@ visit(
     df.open (file_mode::scan, path);
     dat_file_header dh;
     read (df, dh);
-    verify<Codec> (dh);
+    verify (dh);
     Codec codec;
     // Iterate Data File
     bulk_reader<File> r(
diff --git a/beast/nudb/win32_file.h b/beast/nudb/win32_file.h
index ca6a21a93..467f9abf6 100644
--- a/beast/nudb/win32_file.h
+++ b/beast/nudb/win32_file.h
@@ -42,6 +42,9 @@
 # ifndef STRICT
 #  define STRICT
 # endif
+# ifndef WIN32_LEAN_AND_MEAN
+#  define WIN32_LEAN_AND_MEAN
+# endif
 # include <Windows.h>
 # undef NOMINMAX
 # undef UNICODE