diff --git a/.gitignore b/.gitignore
index 33389b6..485c2f2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,6 +9,8 @@ build-macos/
 build-ohos/
 build-windows/
 cmake-build-debug/
+_codeql_build_dir/
+_codeql_detected_source_root
 
 # Generated test binaries and object files
 *.o
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index c1e8cf2..acd5f74 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -1,3 +1,9 @@
 add_executable(url_opener_test url_opener_test.cpp)
 target_link_libraries(url_opener_test PRIVATE nativeapi)
 add_test(NAME url_opener_test COMMAND url_opener_test)
+
+if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+  add_executable(autostart_test autostart_test.cpp)
+  target_link_libraries(autostart_test PRIVATE nativeapi)
+  add_test(NAME autostart_test COMMAND autostart_test)
+endif()
diff --git a/tests/autostart_test.cpp b/tests/autostart_test.cpp
new file mode 100644
index 0000000..5b7f566
--- /dev/null
+++ b/tests/autostart_test.cpp
@@ -0,0 +1,350 @@
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <cstdlib>
+#include <fstream>
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <vector>
+
+#include "../src/autostart.h"
+
+namespace {
+
+// Return a temporary XDG_CONFIG_HOME directory unique to this test run
+static std::string MakeTempConfigDir() {
+  const char* tmpbase = std::getenv("TMPDIR");
+  if (!tmpbase || !*tmpbase)
+    tmpbase = "/tmp";
+  std::string tmpl = std::string(tmpbase) + "/autostart_test_XXXXXX";
+  const char* dir = mkdtemp(tmpl.data());
+  if (!dir) {
+    std::cerr << "mkdtemp failed" << std::endl;
+    return std::string();
+  }
+  return std::string(dir);
+}
+
+// Remove a directory tree (non-recursively safe: only removes known files).
+// Failures are intentionally ignored since this is test cleanup only.
+static void RemoveDesktopFile(const std::string& config_dir, const std::string& id) {
+  std::string path = config_dir + "/autostart/" + id + ".desktop";
+  unlink(path.c_str());
+  rmdir((config_dir + "/autostart").c_str());
+  rmdir(config_dir.c_str());
+}
+
+// Read file contents into a string
+static std::string ReadFile(const std::string& path) {
+  std::ifstream ifs(path);
+  if (!ifs.is_open())
+    return std::string();
+  std::ostringstream oss;
+  oss << ifs.rdbuf();
+  return oss.str();
+}
+
+// Scoped XDG_CONFIG_HOME override to isolate tests
+struct ScopedConfigHome {
+  std::string dir;
+  std::string prev;
+
+  explicit ScopedConfigHome(const std::string& d) : dir(d) {
+    const char* p = std::getenv("XDG_CONFIG_HOME");
+    prev = p ? std::string(p) : std::string();
+    setenv("XDG_CONFIG_HOME", dir.c_str(), 1);
+  }
+
+  ~ScopedConfigHome() {
+    if (prev.empty()) {
+      unsetenv("XDG_CONFIG_HOME");
+    } else {
+      setenv("XDG_CONFIG_HOME", prev.c_str(), 1);
+    }
+  }
+};
+
+int RunTests() {
+  using namespace nativeapi;
+
+  // IsSupported returns true on Linux
+  {
+    if (!AutoStart::IsSupported()) {
+      std::cerr << "AutoStart::IsSupported() should return true on Linux." << std::endl;
+      return 1;
+    }
+  }
+
+  // Constructors and getters
+  {
+    const std::string tmpDir = MakeTempConfigDir();
+    if (tmpDir.empty())
+      return 1;
+    ScopedConfigHome scope(tmpDir);
+
+    AutoStart as("com.example.testapp", "TestApp");
+    if (as.GetId() != "com.example.testapp") {
+      std::cerr << "GetId() should return 'com.example.testapp', got '" << as.GetId() << "'"
+                << std::endl;
+      rmdir(tmpDir.c_str());
+      return 1;
+    }
+    if (as.GetDisplayName() != "TestApp") {
+      std::cerr << "GetDisplayName() should return 'TestApp', got '" << as.GetDisplayName() << "'"
+                << std::endl;
+      rmdir(tmpDir.c_str());
+      return 1;
+    }
+    rmdir(tmpDir.c_str());
+  }
+
+  // SetDisplayName
+  {
+    const std::string tmpDir = MakeTempConfigDir();
+    if (tmpDir.empty())
+      return 1;
+    ScopedConfigHome scope(tmpDir);
+
+    AutoStart as("com.example.testapp", "OriginalName");
+    if (!as.SetDisplayName("NewName")) {
+      std::cerr << "SetDisplayName() should return true." << std::endl;
+      rmdir(tmpDir.c_str());
+      return 1;
+    }
+    if (as.GetDisplayName() != "NewName") {
+      std::cerr << "GetDisplayName() after SetDisplayName() should return 'NewName', got '"
+                << as.GetDisplayName() << "'" << std::endl;
+      rmdir(tmpDir.c_str());
+      return 1;
+    }
+    rmdir(tmpDir.c_str());
+  }
+
+  // SetProgram / GetExecutablePath / GetArguments
+  {
+    const std::string tmpDir = MakeTempConfigDir();
+    if (tmpDir.empty())
+      return 1;
+    ScopedConfigHome scope(tmpDir);
+
+    AutoStart as("com.example.testapp", "TestApp");
+    std::vector<std::string> args = {"--minimized", "--tray"};
+    if (!as.SetProgram("/usr/bin/testapp", args)) {
+      std::cerr << "SetProgram() should return true." << std::endl;
+      rmdir(tmpDir.c_str());
+      return 1;
+    }
+    if (as.GetExecutablePath() != "/usr/bin/testapp") {
+      std::cerr << "GetExecutablePath() should return '/usr/bin/testapp', got '"
+                << as.GetExecutablePath() << "'" << std::endl;
+      rmdir(tmpDir.c_str());
+      return 1;
+    }
+    auto gotArgs = as.GetArguments();
+    if (gotArgs != args) {
+      std::cerr << "GetArguments() returned unexpected values." << std::endl;
+      rmdir(tmpDir.c_str());
+      return 1;
+    }
+    rmdir(tmpDir.c_str());
+  }
+
+  // Enable creates .desktop file and IsEnabled returns true
+  {
+    const std::string tmpDir = MakeTempConfigDir();
+    if (tmpDir.empty())
+      return 1;
+    ScopedConfigHome scope(tmpDir);
+
+    const std::string testId = "com.example.autostarttest";
+    AutoStart as(testId, "AutoStartTest");
+    as.SetProgram("/usr/bin/testapp", {});
+
+    if (!as.Enable()) {
+      std::cerr << "Enable() should return true." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+
+    if (!as.IsEnabled()) {
+      std::cerr << "IsEnabled() should return true after Enable()." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+
+    RemoveDesktopFile(tmpDir, testId);
+  }
+
+  // Disable removes .desktop file and IsEnabled returns false
+  {
+    const std::string tmpDir = MakeTempConfigDir();
+    if (tmpDir.empty())
+      return 1;
+    ScopedConfigHome scope(tmpDir);
+
+    const std::string testId = "com.example.autostarttest";
+    AutoStart as(testId, "AutoStartTest");
+    as.SetProgram("/usr/bin/testapp", {});
+
+    if (!as.Enable()) {
+      std::cerr << "Enable() should return true (precondition for Disable test)." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+
+    if (!as.Disable()) {
+      std::cerr << "Disable() should return true." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+
+    if (as.IsEnabled()) {
+      std::cerr << "IsEnabled() should return false after Disable()." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+
+    RemoveDesktopFile(tmpDir, testId);
+  }
+
+  // Disable is idempotent (no error when file does not exist)
+  {
+    const std::string tmpDir = MakeTempConfigDir();
+    if (tmpDir.empty())
+      return 1;
+    ScopedConfigHome scope(tmpDir);
+
+    AutoStart as("com.example.autostarttest", "AutoStartTest");
+    if (!as.Disable()) {
+      std::cerr << "Disable() on non-existent entry should return true (idempotent)." << std::endl;
+      rmdir(tmpDir.c_str());
+      return 1;
+    }
+    rmdir(tmpDir.c_str());
+  }
+
+  // IsEnabled returns false before Enable() is called
+  {
+    const std::string tmpDir = MakeTempConfigDir();
+    if (tmpDir.empty())
+      return 1;
+    ScopedConfigHome scope(tmpDir);
+
+    AutoStart as("com.example.autostarttest", "AutoStartTest");
+    if (as.IsEnabled()) {
+      std::cerr << "IsEnabled() should return false before Enable() is called." << std::endl;
+      rmdir(tmpDir.c_str());
+      return 1;
+    }
+    rmdir(tmpDir.c_str());
+  }
+
+  // Enable() writes valid .desktop content
+  {
+    const std::string tmpDir = MakeTempConfigDir();
+    if (tmpDir.empty())
+      return 1;
+    ScopedConfigHome scope(tmpDir);
+
+    const std::string testId = "com.example.contenttest";
+    AutoStart as(testId, "ContentTestApp");
+    as.SetProgram("/usr/local/bin/myapp", {"--flag", "value with space"});
+
+    if (!as.Enable()) {
+      std::cerr << "Enable() should return true." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+
+    std::string desktopPath = tmpDir + "/autostart/" + testId + ".desktop";
+    std::string content = ReadFile(desktopPath);
+
+    if (content.find("[Desktop Entry]") == std::string::npos) {
+      std::cerr << "Desktop file missing [Desktop Entry] section." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+    if (content.find("Type=Application") == std::string::npos) {
+      std::cerr << "Desktop file missing 'Type=Application'." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+    if (content.find("Name=ContentTestApp") == std::string::npos) {
+      std::cerr << "Desktop file missing 'Name=ContentTestApp'." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+    if (content.find("Exec=") == std::string::npos) {
+      std::cerr << "Desktop file missing 'Exec=' line." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+    if (content.find("/usr/local/bin/myapp") == std::string::npos) {
+      std::cerr << "Desktop file Exec line missing executable path." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+    if (content.find("Hidden=false") == std::string::npos) {
+      std::cerr << "Desktop file missing 'Hidden=false'." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+    if (content.find("X-GNOME-Autostart-enabled=true") == std::string::npos) {
+      std::cerr << "Desktop file missing 'X-GNOME-Autostart-enabled=true'." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+
+    RemoveDesktopFile(tmpDir, testId);
+  }
+
+  // Enable() then Enable() again updates the entry (re-enables)
+  {
+    const std::string tmpDir = MakeTempConfigDir();
+    if (tmpDir.empty())
+      return 1;
+    ScopedConfigHome scope(tmpDir);
+
+    const std::string testId = "com.example.autostarttest";
+    AutoStart as(testId, "AutoStartTest");
+    as.SetProgram("/usr/bin/testapp", {});
+
+    if (!as.Enable()) {
+      std::cerr << "Enable() first call should return true." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+    // Update program and enable again
+    as.SetProgram("/usr/bin/testapp2", {});
+    if (!as.Enable()) {
+      std::cerr << "Enable() second call should return true." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+    if (!as.IsEnabled()) {
+      std::cerr << "IsEnabled() should return true after second Enable()." << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+
+    std::string desktopPath = tmpDir + "/autostart/" + testId + ".desktop";
+    std::string content = ReadFile(desktopPath);
+    if (content.find("/usr/bin/testapp2") == std::string::npos) {
+      std::cerr << "Desktop file should reference updated executable after second Enable()."
+                << std::endl;
+      RemoveDesktopFile(tmpDir, testId);
+      return 1;
+    }
+
+    RemoveDesktopFile(tmpDir, testId);
+  }
+
+  return 0;
+}
+
+}  // namespace
+
+int main() {
+  return RunTests();
+}