can you provide an example that would illustrate the problem? The file you submitted fails because projects do not include setup.py. I would advise to use zc.buildout 1.6.0 and see if issue persists.
Sure, I added minimalistic setup.py to both subprojects: http://artiemestieri.tn.it/~lele/test-buildout-2.tar.gz As is, executing a buildout (btw, using latest 1.6.1 now), I get: $ buildout Creating directory '/tmp/test-zcb/bin'. Creating directory '/tmp/test-zcb/parts'. Creating directory '/tmp/test-zcb/develop-eggs'. Develop: '/tmp/test-zcb/src/proj2' Installing extra-parts-from-proj2. Note it does not even mention anything from proj1, even if it is surely loading its configuration snippets: $ buildout annotate | grep proj1 proj1 += /tmp/test-zcb/src/proj1/devel.cfg += /tmp/test-zcb/src/proj1/base.cfg and it does not install the [python] recipe neither... If I comment out the last line in the top level projects.cfg, the one that includes the proj2/devel.cfg, I get: $ buildout Develop: '/tmp/test-zcb/src/proj1' Running uninstall recipe. Installing python. Generated interpreter '/tmp/test-zcb/bin/python'. This time it installed the [python] recipe, and effectively $ bin/python -m project1 Hello from project1 with the extra package too: $ bin/python -c "import faker; print faker.__version__" 0.0.4 So, it really seems that loading the projX extension clobbers the previous settings, but I cannot see what I'm doing wrong. Thanks a lot for your time, and for any enlightenment :-) ciao, lele. PS: I won't be able to follow the group for the next two weeks as I'm taking a long awaited vacation.