Hi, We have been working on using buildout with a develop package depending on numpy, and ran into trouble because 'numpy' is not specified in the package 'install_requires'. Specifically, we have something like this: [buildout] parts = nibabel-target mypy [nibabel-target] recipe = zc.recipe.egg:develop setup = src/nibabel [mypy] recipe = zc.recipe.egg:script eggs = nibabel interpreter = py 'nibabel' needs to import numpy to install, but does not specify 'numpy' in its setup.py install_requires, because pip install of numpy is fragile, and we wanted to error early in general for an attempted pip install of nibabel, if numpy was not present. But of course the script above raises an error for the 'nibabel-target' part, because of missing numpy: ------------- RuntimeError: Cannot import package "numpy" - is it installed? While: Installing nibabel-target. An internal error occurred due to a bug in either zc.buildout or in a recipe being used: ------------ What we would very much like to do, is to be able to specify the missing install_requires for this package (and for others we are thinking of working with), in the recipe - something like: [nibabel-target] recipe = zc.recipe.egg:develop setup = src/nibabel install-requires = numpy but we couldn't immediately see a way of specifying such a dependency. A quick look at the Develop code in zc/recipe/egg/custom.py suggested that there wasn't an easy way to add some needed egg onto the path at this point. Is there anything we missed that we should have tried? If not, what would be the best way to solve our problem? A modified recipe? Best, Matthew