diff --git a/.github/workflows/cibuild.yml b/.github/workflows/cibuild.yml
index a03b5a26420..1e1e61bdf98 100644
--- a/.github/workflows/cibuild.yml
+++ b/.github/workflows/cibuild.yml
@@ -113,6 +113,10 @@ jobs:
           CXX: ${{ matrix.CXX }}
       run: cmake --build build --config ${{ matrix.Configuration }} --parallel $(nproc || echo 4)
 
+    - name: Run CTest
+      working-directory: build
+      run: ctest --parallel $(nproc || echo 4)
+
     - name: Make package
       if: ${{ steps.cmake-build.outcome == 'success' }}
       id: make-package
@@ -171,6 +175,10 @@ jobs:
       shell: alpine.sh {0}
       run: cmake --build build --config ${{ matrix.Configuration }} --parallel $(nproc || echo 4)
 
+    - name: Run CTest
+      shell: alpine.sh {0}
+      run: ctest --parallel $(nproc || echo 4)
+
   build-macos:
     name: macOS ${{ matrix.Configuration }} ${{ matrix.Platform }}
     runs-on: macos-latest
@@ -197,3 +205,6 @@ jobs:
 
     - name: Run CMake Build
       run: cmake --build build --config ${{ matrix.Configuration }} --parallel $(sysctl -n hw.ncpu || echo 4)
+
+    - name: Run CTest
+      run: ctest --parallel $(sysctl -n hw.ncpu || echo 4)
diff --git a/.gitmodules b/.gitmodules
index d653b46d1ba..62beff6839d 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -46,3 +46,7 @@
 [submodule "Externals/xrLuaFix"]
 	path = Externals/xrLuaFix
 	url = https://github.com/OpenXRay/xrLuaFix.git
+[submodule "Externals/doctest"]
+	path = Externals/doctest
+	url = https://github.com/doctest/doctest.git
+	branch = master
diff --git a/CMakeLists.txt b/CMakeLists.txt
index b24593b8b1e..35ea73bba57 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -298,6 +298,13 @@ add_subdirectory(src)
 add_subdirectory(res)
 add_subdirectory(misc)
 
+# Tests
+option(BUILD_TESTS "Build tests" ON)
+if (BUILD_TESTS)
+    include(CTest)
+    add_subdirectory(tests)
+endif()
+
 get_property(LIB64 GLOBAL PROPERTY FIND_LIBRARY_USE_LIB64_PATHS)
 
 if ("${LIB64}" STREQUAL "TRUE")
diff --git a/Externals/CMakeLists.txt b/Externals/CMakeLists.txt
index 6ee73375534..738f1cda7ff 100644
--- a/Externals/CMakeLists.txt
+++ b/Externals/CMakeLists.txt
@@ -23,3 +23,5 @@ if (NOT TARGET xrLuabind)
         "Read the build instructions: https://github.com/OpenXRay/xray-16/wiki"
     )
 endif()
+
+add_subdirectory(doctest EXCLUDE_FROM_ALL)
diff --git a/Externals/doctest b/Externals/doctest
new file mode 160000
index 00000000000..ae7a13539fb
--- /dev/null
+++ b/Externals/doctest
@@ -0,0 +1 @@
+Subproject commit ae7a13539fb71f270b87eb2e874fbac80bc8dda2
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
new file mode 100644
index 00000000000..bef9148cd2f
--- /dev/null
+++ b/tests/CMakeLists.txt
@@ -0,0 +1 @@
+add_subdirectory(xrCore)
diff --git a/tests/xrCore/CMakeLists.txt b/tests/xrCore/CMakeLists.txt
new file mode 100644
index 00000000000..a2fd296c839
--- /dev/null
+++ b/tests/xrCore/CMakeLists.txt
@@ -0,0 +1,9 @@
+
+add_executable(
+    xrCoreTests
+    main.cpp
+    xr_ini_test.cpp)
+
+target_link_libraries(xrCoreTests xrCore doctest::doctest)
+target_include_directories(xrCoreTests PRIVATE "${CMAKE_SOURCE_DIR}/src")
+add_test(NAME xrCoreTests COMMAND xrCoreTests)
diff --git a/tests/xrCore/main.cpp b/tests/xrCore/main.cpp
new file mode 100644
index 00000000000..fec512c36de
--- /dev/null
+++ b/tests/xrCore/main.cpp
@@ -0,0 +1,17 @@
+#define DOCTEST_CONFIG_IMPLEMENT
+#include <doctest/doctest.h>
+
+#include <Common/Platform.hpp>
+#include <xrCore/xrCore.h>
+
+int main(int argc, char** argv)
+{
+  doctest::Context context;
+
+  context.applyCommandLine(argc, argv);
+
+  // Initialize memory
+  Memory._initialize();
+
+  return context.run();
+}
diff --git a/tests/xrCore/xr_ini_test.cpp b/tests/xrCore/xr_ini_test.cpp
new file mode 100644
index 00000000000..0c4d7291c05
--- /dev/null
+++ b/tests/xrCore/xr_ini_test.cpp
@@ -0,0 +1,88 @@
+#include <doctest/doctest.h>
+
+#include <Common/Platform.hpp>
+#include <xrCore/xrCore.h>
+#include <xrCore/xr_types.h>
+
+#include <xrCore/xr_ini.h>
+
+CInifile
+read_from_string(pcstr str,
+                 CInifile::allow_include_func_t allow_include = nullptr) {
+  IReader reader = IReader(const_cast<pstr>(str), xr_strlen(str));
+  return CInifile(&reader, "test.ini", allow_include);
+}
+
+TEST_CASE("parse empty file") {
+  CInifile ini = read_from_string("");
+
+  CHECK_EQ(ini.section_count(), 0);
+}
+
+TEST_CASE("parse empty section") {
+  CInifile ini = read_from_string("[a]");
+
+  CHECK_EQ(ini.section_count(), 1);
+  CHECK_UNARY(ini.section_exist("a"));
+}
+
+TEST_CASE("parse simple section") {
+  CInifile ini = read_from_string(
+      R"ini(
+[a]
+key = value
+)ini");
+
+  CHECK_UNARY(ini.section_exist("a"));
+  CHECK_UNARY(ini.line_exist("a", "key"));
+  CHECK_EQ(xr_strcmp(ini.read<pcstr>("a", "key"), "value"), 0);
+}
+
+TEST_CASE("parse integer value") {
+  CInifile ini = read_from_string(
+      R"ini(
+[a]
+key = 123
+)ini");
+
+  CHECK_UNARY(ini.section_exist("a"));
+  CHECK_UNARY(ini.line_exist("a", "key"));
+  CHECK_EQ(ini.read<u32>("a", "key"), 123);
+}
+
+TEST_CASE("Parse float value") {
+  CInifile ini = read_from_string(
+      R"ini(
+[a]
+key = 123.456
+)ini");
+
+  CHECK_UNARY(ini.section_exist("a"));
+  CHECK_UNARY(ini.line_exist("a", "key"));
+  CHECK_EQ(ini.read<f32>("a", "key"), 123.456f);
+}
+
+TEST_CASE("Parse quoted value") {
+  CInifile ini = read_from_string(
+      R"ini(
+[a]
+key = "value"
+)ini");
+
+  CHECK_UNARY(ini.section_exist("a"));
+  CHECK_UNARY(ini.line_exist("a", "key"));
+  CHECK_EQ(xr_strcmp(ini.read<pcstr>("a", "key"), "\"value\""), 0);
+}
+
+TEST_CASE("Parse multiline value") {
+  CInifile ini = read_from_string(
+      R"ini(
+[a]
+key = "multiline
+value"
+)ini");
+
+  CHECK_UNARY(ini.section_exist("a"));
+  CHECK_UNARY(ini.line_exist("a", "key"));
+  CHECK_EQ(xr_strcmp(ini.read<pcstr>("a", "key"), "\"multiline\r\nvalue\""), 0);
+}