diff --git a/src/config.h b/src/config.h
index 1d6922a..e48a034 100644
--- a/src/config.h
+++ b/src/config.h
@@ -84,7 +84,9 @@
  *
  * This will handle "gids" correctly once the permissions are set right.
  */
+#ifndef __EMSCRIPTEN__ /* the browser has no user ids to drop */
 #define SAFE_SETUID
+#endif
 
 /*
  * This flag enables the "POSIX" methods for "SAFE_SETUID".
diff --git a/src/init2.c b/src/init2.c
index c334a9a..eff3c1f 100644
--- a/src/init2.c
+++ b/src/init2.c
@@ -12,6 +12,10 @@
 
 #include "init.h"
 
+#ifdef __EMSCRIPTEN__
+#include <sys/stat.h>
+#endif
+
 #ifdef RUNTIME_PRIVATE_USER_PATH
 /*
  * This is a hook so the main program can set a runtime value for the private
@@ -212,6 +216,25 @@ void init_file_paths(char* path)
 
 #endif /* VM */
 
+#ifdef __EMSCRIPTEN__
+    /* The browser build: the game files are preloaded in /sil/lib/ (read only); the saved games, the high
+     * scores and the user files are in /sil-user/, which the page keeps in the browser (IndexedDB); the raw
+     * data files are made on every start, in memory (/sil-data/). */
+    string_free(ANGBAND_DIR_DATA);
+    string_free(ANGBAND_DIR_APEX);
+    string_free(ANGBAND_DIR_SAVE);
+    string_free(ANGBAND_DIR_USER);
+    ANGBAND_DIR_DATA = string_make("/sil-data/");
+    ANGBAND_DIR_APEX = string_make("/sil-user/apex/");
+    ANGBAND_DIR_SAVE = string_make("/sil-user/save/");
+    ANGBAND_DIR_USER = string_make("/sil-user/user/");
+    mkdir("/sil-data", 0755);
+    mkdir("/sil-user", 0755);
+    mkdir("/sil-user/apex", 0755);
+    mkdir("/sil-user/save", 0755);
+    mkdir("/sil-user/user", 0755);
+#endif /* __EMSCRIPTEN__ */
+
 #ifdef NeXT
 
     /* Allow "fat binary" usage with NeXT */
diff --git a/src/main.c b/src/main.c
index 94600f7..f480827 100644
--- a/src/main.c
+++ b/src/main.c
@@ -19,6 +19,10 @@
 
 #include "main.h"
 
+#ifdef __EMSCRIPTEN__
+extern void cw_set_nokeypad_keys(const char* keys); /* curses-web/curses.h */
+#endif
+
 /*
  * Sil-y: game in progress
  */
@@ -373,6 +377,11 @@ int main(int argc, char* argv[])
     /* Save the "program name" XXX XXX XXX */
     argv0 = argv[0];
 
+#ifdef __EMSCRIPTEN__
+    /* The arrow keys and Home/End/PageUp/PageDown walk (the curses layer sends these digits for them) */
+    cw_set_nokeypad_keys("82467193");
+#endif
+
 #ifdef USE_286
     /* Attempt to use XMS (or EMS) memory for swap space */
     if (_OvrInitExt(0L, 0L))
diff --git a/src/util.c b/src/util.c
index bdc0c1d..408896c 100644
--- a/src/util.c
+++ b/src/util.c
@@ -60,6 +60,13 @@ void user_name(char* buf, size_t len, int id)
 {
     struct passwd* pw;
 
+#ifdef __EMSCRIPTEN__
+    /* the browser has no user names */
+    (void)id;
+    my_strcpy(buf, "Player", len);
+    return;
+#endif
+
     /* Look up the user name */
     if ((pw = getpwuid(id)))
     {