I’d argue that FEniCs was a prime example of this in some ways, at least earlier in it’s history. I started using it in about 2014. It was not exactly what I w

I’d argue that FEniCs was a prime example of this in some ways, at least earlier in it’s history. I started using it in about 2014. It was not exactly what I would call a simple project. It used to be an ordeal to build, could only easily be used via Docker, ported to Python 3 a long long time after most of it’s dependencies did, had an unstable C++ API that changes were not documented for but nonetheless you were required to use if you wanted for reasonable performance for some calculations, etc. The national supercomputing centre in my country managed to only get one version to build because it was so poorly specified at the time and basically only supported Ubuntu! FEniCsX is considerably better usability wise, but that’s the result of hard lessons learnt.