diff -ur a/LibKeyFinder.pro b/LibKeyFinder.pro
--- a/LibKeyFinder.pro	2017-03-12 23:41:10.000000000 +0100
+++ b/LibKeyFinder.pro	2017-03-23 16:49:06.236738498 +0100
@@ -30,7 +30,8 @@
 VERSION = 2.2.0
 
 CONFIG += c++11
-QMAKE_CXXFLAGS += -std=c++11
+QMAKE_CXXFLAGS_RELEASE -= -O2
+QMAKE_CXXFLAGS += -std=c++11 -Os -fomit-frame-pointer
 
 DEFINES += LIBKEYFINDER_LIBRARY
 
diff -ur a/tests/tests.pro b/tests/tests.pro
--- a/tests/tests.pro	2017-03-23 16:47:17.280248215 +0100
+++ b/tests/tests.pro	2017-03-23 16:48:28.386799769 +0100
@@ -27,8 +27,9 @@
 CONFIG -= qt
 
 CONFIG += c++11
-LIBS += -stdlib=libc++
-QMAKE_CXXFLAGS += -std=c++11 -stdlib=libc++
+LIBS += -L..
+QMAKE_CXXFLAGS_RELEASE -= -O2
+QMAKE_CXXFLAGS += -std=c++11 -Os -fomit-frame-pointer
 
 LIBS += -lkeyfinder