diff --git a/src/client/client.h b/src/client/client.h
index 9f898e78ab63..42049791f1cd 100644
--- a/src/client/client.h
+++ b/src/client/client.h
@@ -36,9 +36,12 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "network/peerhandler.h"
 #include "gameparams.h"
 #include "clientdynamicinfo.h"
-#include <fstream>
 #include "util/numeric.h"
 
+#ifdef SERVER
+#error Do not include in server builds
+#endif
+
 #define CLIENT_CHAT_MESSAGE_LIMIT_PER_10S 10.0f
 
 struct ClientEvent;
diff --git a/src/client/clientenvironment.h b/src/client/clientenvironment.h
index 407473be7524..bdb8b97260d6 100644
--- a/src/client/clientenvironment.h
+++ b/src/client/clientenvironment.h
@@ -24,6 +24,10 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "activeobjectmgr.h" // client::ActiveObjectMgr
 #include <set>
 
+#ifdef SERVER
+#error Do not include in server builds
+#endif
+
 class ClientSimpleObject;
 class ClientMap;
 class ClientScripting;
diff --git a/src/client/game.h b/src/client/game.h
index c1e8bb0a5565..0282e5ea9411 100644
--- a/src/client/game.h
+++ b/src/client/game.h
@@ -22,6 +22,10 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "irrlichttypes.h"
 #include <string>
 
+#ifdef SERVER
+#error Do not include in server builds
+#endif
+
 class InputHandler;
 class ChatBackend;
 class RenderingEngine;
diff --git a/src/client/renderingengine.h b/src/client/renderingengine.h
index 948485d82dc8..b8ae62fc4b31 100644
--- a/src/client/renderingengine.h
+++ b/src/client/renderingengine.h
@@ -30,6 +30,10 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 // include the shadow mapper classes too
 #include "client/shadows/dynamicshadowsrender.h"
 
+#ifdef SERVER
+#error Do not include in server builds
+#endif
+
 struct VideoDriverInfo {
 	std::string name;
 	std::string friendly_name;
diff --git a/src/client/sound.h b/src/client/sound.h
index 132da708ecfa..8b19f7761a63 100644
--- a/src/client/sound.h
+++ b/src/client/sound.h
@@ -26,6 +26,10 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include <unordered_set>
 #include <vector>
 
+#ifdef SERVER
+#error Do not include in server builds
+#endif
+
 struct SoundSpec;
 
 class SoundFallbackPathProvider
diff --git a/src/main.cpp b/src/main.cpp
index e7ec6dd53835..763a8ae37190 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -17,9 +17,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
-#include "irrlichttypes.h" // must be included before anything irrlicht, see comment in the file
+#include "irrlichttypes_bloated.h"
 #include "irrlicht.h" // createDevice
-#include "irrlichttypes_extrabloated.h"
 #include "irrlicht_changes/printing.h"
 #include "benchmark/benchmark.h"
 #include "chat_interface.h"
@@ -28,7 +27,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "server.h"
 #include "filesys.h"
 #include "version.h"
-#include "client/game.h"
 #include "defaultsettings.h"
 #include "gettext.h"
 #include "log.h"
diff --git a/src/unittest/test.cpp b/src/unittest/test.cpp
index 761c908135d5..1fd9001bfcf5 100644
--- a/src/unittest/test.cpp
+++ b/src/unittest/test.cpp
@@ -19,7 +19,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #include "test.h"
 
-#include "client/sound.h"
 #include "nodedef.h"
 #include "itemdef.h"
 #include "dummygamedef.h"
diff --git a/src/util/string.h b/src/util/string.h
index ac45463d7f41..beb75b6d3288 100644
--- a/src/util/string.h
+++ b/src/util/string.h
@@ -20,7 +20,9 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #pragma once
 
 #include "irrlichttypes_bloated.h"
+#ifndef SERVER
 #include "irrString.h"
+#endif
 #include <cstdlib>
 #include <string>
 #include <string_view>
@@ -732,6 +734,7 @@ inline std::string str_join(const std::vector<std::string> &list,
 	return oss.str();
 }
 
+#ifndef SERVER
 /**
  * Create a UTF8 std::string from an irr::core::stringw.
  */
@@ -749,6 +752,7 @@ inline irr::core::stringw utf8_to_stringw(std::string_view input)
 	std::wstring str = utf8_to_wide(input);
 	return irr::core::stringw(str.c_str(), str.size());
 }
+#endif
 
 /**
  * Sanitize the name of a new directory. This consists of two stages: