Peter, thanks for the confirmation that in your installation of the PetitYAML grammar all tests are green. I wonder how you did it. This is what I did: 1. I put Pillar on the back burner for the moment and 2. I went for a pristine Pharo 6.0 Latest update: #60510 image (a.k.a. 6.1). 3. Then I installed PetitParser only through the catalog -- the entry is still tagged for Pharo 5.0 4. Then I added PetitYAML Name: PetitYAML-PhilippeBack.11 Author: PhilippeBack Time: 29 May 2017, 12:53:55.994195 pm UUID: d7658233-112c-754c-81a7-d60139bb9549 taken from MCSmalltalkhubRepository owner: 'Moose' project: 'PetitParser' user: '' password: '' 5. Running the tests gave me 76 run -- 76 errors What am I missing here? Is there an easy workaround to get PetitParser with PetitYAML into 6.0-#60510 (a.k.a. 6.1) ? --Hannes