diff --git a/game.cpp b/game.cpp
index 7dcf91bc..e4e9e3d6 100644
--- a/game.cpp
+++ b/game.cpp
@@ -144,7 +144,7 @@ cellwalker cwt;       // single player character position
 inline cell*& singlepos() { return cwt.c; }
 inline bool singleused() { return !(shmup::on || multi::players > 1); }
 
-mt19937 r;
+std::mt19937 r;
 
 void shrand(int i) {
   r.seed(i);
@@ -161,7 +161,7 @@ ld hrandf() {
   }
 
 int hrandstate() {
-  mt19937 r2 = r;
+  std::mt19937 r2 = r;
   return r2() & HRANDMAX;
   }
 
diff --git a/hyper.h b/hyper.h
index e313e831..d45f8db3 100644
--- a/hyper.h
+++ b/hyper.h
@@ -10,7 +10,34 @@
 
 namespace hr {
 
-using namespace std;
+// functions and types used from the standard library
+using std::vector;
+using std::map;
+using std::array;
+using std::unordered_map;
+using std::sort;
+using std::multimap;
+using std::set;
+using std::string;
+using std::function;
+using std::pair;
+using std::tuple;
+using std::shared_ptr;
+using std::make_shared;
+using std::min;
+using std::max;
+using std::make_pair;
+using std::tie;
+using std::queue;
+using std::swap;
+using std::complex;
+using std::reverse;
+using std::real;
+using std::imag;
+using std::stable_sort;
+using std::out_of_range;
+using std::get;
+using std::random_shuffle;
 
 // genus (in grammar)
 #define GEN_M 0
@@ -369,9 +396,7 @@ string cts(char c);
 string its(int i);
 int hrand(int i);
 
-#ifndef STDSIZE
 template<class T> int size(const T& x) {return x.size(); }
-#endif
 
 // initialize the achievement system.
 void achievement_init();
diff --git a/inventory.cpp b/inventory.cpp
index abfa0d0b..34be2d38 100644
--- a/inventory.cpp
+++ b/inventory.cpp
@@ -93,7 +93,7 @@ namespace hr { namespace inv {
     return int(mirrorqty0(orb) * sqrt(1.000001+items[itPower]/20.));
     }
     
-  mt19937 invr;
+  std::mt19937 invr;
   
   void sirand(int i) {
     invr.seed(i);
diff --git a/langen.cpp b/langen.cpp
index 1600ae50..9230e542 100644
--- a/langen.cpp
+++ b/langen.cpp
@@ -9,14 +9,17 @@
 
 #include <map>
 #include <string>
-#include <stdio.h>
+#include <cstdio>
 #include <vector>
-#include <stdlib.h>
-using namespace std;
+#include <cstdlib>
+#include <set>
+
+using std::string;
+using std::map;
+using std::vector;
+using std::set;
 
-#ifndef STDSIZE
 template<class T> int size(const T& x) { return x.size(); }
-#endif
 
 #define NUMLAN 7
 
@@ -44,8 +47,6 @@ struct noun {
 
 dictionary<noun> nouns[NUMLAN];
 
-#include <set>
-
 int utfsize(char c) {
   unsigned char cu = c;
   if(cu < 128) return 1;
diff --git a/rogueviz.cpp b/rogueviz.cpp
index 2c506e41..561ebe86 100644
--- a/rogueviz.cpp
+++ b/rogueviz.cpp
@@ -577,7 +577,7 @@ namespace sag {
     return cost;
     }
   
-  mt19937 los;
+  std::mt19937 los;
 
   bool infullsa;