diff --git a/CMakeLists.txt b/CMakeLists.txt
index 10b3301f..03842f91 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -113,22 +113,27 @@ else()
     list( APPEND IXWEBSOCKET_HEADERS ixwebsocket/IXSelectInterruptEventFd.h)
 endif()
 
-if (WIN32)
-  set(USE_MBED_TLS TRUE)
-endif()
+option(USE_TLS "Enable TLS support" FALSE)
 
 if (USE_TLS)
+    if (WIN32)
+        option(USE_MBED_TLS "Use Mbed TLS" ON)
+    else()
+        option(USE_MBED_TLS "Use Mbed TLS" OFF)
+    endif()
+    option(USE_OPEN_SSL "Use OpenSSL" OFF)
+    
     if (USE_MBED_TLS)
         list( APPEND IXWEBSOCKET_HEADERS ixwebsocket/IXSocketMbedTLS.h)
         list( APPEND IXWEBSOCKET_SOURCES ixwebsocket/IXSocketMbedTLS.cpp)
     elseif (APPLE AND NOT USE_OPEN_SSL)
         list( APPEND IXWEBSOCKET_HEADERS ixwebsocket/IXSocketAppleSSL.h)
         list( APPEND IXWEBSOCKET_SOURCES ixwebsocket/IXSocketAppleSSL.cpp)
-    elseif (WIN32)
+    elseif (WIN32 AND NOT USE_OPEN_SSL)
         list( APPEND IXWEBSOCKET_HEADERS ixwebsocket/IXSocketSChannel.h)
         list( APPEND IXWEBSOCKET_SOURCES ixwebsocket/IXSocketSChannel.cpp)
     else()
-        set(USE_OPEN_SSL TRUE)
+        set(USE_OPEN_SSL ON)
         list( APPEND IXWEBSOCKET_HEADERS ixwebsocket/IXSocketOpenSSL.h)
         list( APPEND IXWEBSOCKET_SOURCES ixwebsocket/IXSocketOpenSSL.cpp)
     endif()
@@ -145,14 +150,10 @@ if (USE_TLS)
         target_compile_definitions(ixwebsocket PUBLIC IXWEBSOCKET_USE_MBED_TLS)
     elseif (USE_OPEN_SSL)
         target_compile_definitions(ixwebsocket PUBLIC IXWEBSOCKET_USE_OPEN_SSL)
-    elseif (APPLE)
-    elseif (WIN32)
-    else()
-        target_compile_definitions(ixwebsocket PUBLIC IXWEBSOCKET_USE_OPEN_SSL)
     endif()
 endif()
 
-if (APPLE AND USE_TLS AND NOT USE_MBED_TLS)
+if (APPLE AND USE_TLS AND NOT USE_MBED_TLS AND NOT USE_OPEN_SSL)
   target_link_libraries(ixwebsocket "-framework foundation" "-framework security")
 endif()
 
@@ -207,7 +208,7 @@ else()
 endif()
 
 set( IXWEBSOCKET_INCLUDE_DIRS
-    .
+    ${CMAKE_CURRENT_SOURCE_DIR}
 )
 
 if (CMAKE_CXX_COMPILER_ID MATCHES "MSVC")