diff -ruN a/src/config.cpp b/src/config.cpp
--- a/src/config.cpp
+++ b/src/config.cpp
@@ -20,8 +20,14 @@
         const std::string help_roguelike_wizard = "data/rl_help_wizard.txt";
         const std::string death_tomb = "data/death_tomb.txt";
         const std::string death_royal = "data/death_royal.txt";
+        #ifdef __EMSCRIPTEN__
+        // The page keeps /saves in the browser (IndexedDB).
+        const std::string scores = "/saves/scores.dat";
+        std::string save_game = "/saves/game.sav";
+#else
         const std::string scores = "scores.dat";
         std::string save_game = "game.sav";
+#endif
     } // namespace files
 
     // Game options as set on startup and with `=` set options command -CJS-
diff -ruN a/src/headers.h b/src/headers.h
--- a/src/headers.h
+++ b/src/headers.h
@@ -18,7 +18,7 @@
     #include <io.h>
     #include <sys/types.h>
 
-#elif __APPLE__ ||  __linux__ || __NetBSD__ || __MORPHOS__
+#elif __APPLE__ ||  __linux__ || __NetBSD__ || __MORPHOS__ || __EMSCRIPTEN__
 
     #include <pwd.h>
     #include <unistd.h>
diff -ruN a/src/ui_io.cpp b/src/ui_io.cpp
--- a/src/ui_io.cpp
+++ b/src/ui_io.cpp
@@ -521,7 +521,16 @@
 // a certain point, sleep for a second. There would need to be a way of resetting
 // the count, with a call made for commands like run or rest.
 bool checkForNonBlockingKeyPress(int microseconds) {
-#ifdef _WIN32
+#ifdef __EMSCRIPTEN__
+    // There is no stdin to select() on in the browser: look at the keys the page has queued.
+    (void) microseconds;
+
+    timeout(0);
+    int result = getch();
+    timeout(-1);
+
+    return result > 0;
+#elif defined(_WIN32)
     (void) microseconds;
 
     // Ugly non-blocking read...Ugh! -MRC-
@@ -656,7 +665,7 @@
 // Check user permissions on Unix based systems,
 // or if on Windows just return. -MRC-
 bool checkFilePermissions() {
-#ifndef _WIN32
+#if !defined(_WIN32) && !defined(__EMSCRIPTEN__)
     if (0 != setuid(getuid())) {
         perror("Can't set permissions correctly!  Setuid call failed.\n");
         return false;