diff --git a/.ci/ubuntu_install.sh b/.ci/ubuntu_install.sh
index 1951259..2d501a1 100755
--- a/.ci/ubuntu_install.sh
+++ b/.ci/ubuntu_install.sh
@@ -1,3 +1,3 @@
 #!/bin/bash
 apt-get update -qq
-apt-get install cmake git gcc g++ make qtbase5-dev -qq
+apt-get install cmake git gcc g++ make ninja-build qtbase5-dev -qq
diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
index 6c1c322..dc26164 100644
--- a/.github/workflows/ubuntu.yml
+++ b/.github/workflows/ubuntu.yml
@@ -19,6 +19,6 @@ jobs:
     - name: Install packages
       run: sudo .ci/ubuntu_install.sh
     - name: Configure CMake
-      run: cmake -B ${{github.workspace}}/build -DCMAKE_BUILD_TYPE=${{env.BUILD_TYPE}} -DBUILD_SHARED=OFF
+      run: cmake -B ${{github.workspace}}/build -DCMAKE_BUILD_TYPE=${{env.BUILD_TYPE}} -DBUILD_SHARED=OFF -GNinja
     - name: Build
       run: cmake --build ${{github.workspace}}/build --config ${{env.BUILD_TYPE}}
diff --git a/src/3rdparty/lua54/CMakeLists.txt b/src/3rdparty/lua54/CMakeLists.txt
index a68a690..af7c8e7 100644
--- a/src/3rdparty/lua54/CMakeLists.txt
+++ b/src/3rdparty/lua54/CMakeLists.txt
@@ -71,9 +71,13 @@ target_include_directories(xmppbotlua PUBLIC
     ${CMAKE_CURRENT_SOURCE_DIR}
 )
 
+if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+    set(LUA_DEFINES -DLUA_USE_LINUX)
+endif()
+
 target_compile_definitions(xmppbotlua PUBLIC
     -DLUA_COMPAT_5_2
-    -DLUA_USE_LINUX
+    ${LUA_DEFINES}
 )
 
 target_link_libraries(xmppbotlua PUBLIC