Hi and welcome to devnet, Because it's complex to integrate one build system with another. What 3rd party is it ?

Finally fixed it, i used a .qmake.conf file to store the root directory in a shared variable, for those who are interested, here are my 3 .pro files : project.pro TEMPLATE = subdirs CONFIG += ordered c++11 SUBDIRS = ircbot \ myApp myApp.depends = ircbot mylib.pro DESTDIR = $$lib_dir TARGET = mylib TEMPLATE = lib CONFIG += staticlib SOURCES += ... HEADERS += ... FORMS += ... myApp.pro DESTDIR = $$bin_dir TARGET = myApp TEMPLATE = app LIBS += $$lib_dir/libmylib.a INCLUDEPATH += ../mylib SOURCES = ... HEADERS += ... FORMS += ... and finally, the .qmake.conf file : lib_dir=$$PWD/lib bin_dir=$$PWD/bin this successfully creates this project structure : bin myApp.exe lib mylib.a project.pro .qmake.conf myApp myApp.pro mylib mylib.pro + a build directory anywhere i want

You're welcome ! Svn allows some interesting things like the use of properties that can simplify some handling for e.g. your files header.