Hi, nestsimulator-2.18.0 fails PyNEST installation as requesting libgsl.so.23 while libgsl.so.25 is available (see brelow --1-- log of installcheck for PyNEST tests) cmake reports no errors with GSL (see bleow --2-- log extract of cmake output ) configuration: linux manjaro latest system update 2019-09-05 Sorry for my ignorance : is there a way to force linking with most recent gsl library ? Or is it necessary to install also the old library version somehow? If then how ? Thank you in advance for any help Samuel Bottani --1-- Phase 7: Running PyNEST tests. ------------------------------ Using nosetests. Failure: ImportError (libgsl.so.23: cannot open shared object file: No such file or directory) ... ERROR Failure: ImportError (libgsl.so.23: cannot open shared object file: No such file or directory) ... ERROR ERROR: Failure: ImportError (libgsl.so.23: cannot open shared object file: No such file or directory) File "/usr/lib/python3.7/site-packages/nose/failure.py", line 39, in runTest ImportError: libgsl.so.23: cannot open shared object file: No such file or directory ERROR: Failure: ImportError (libgsl.so.23: cannot open shared object file: No such file or directory) File "/usr/lib/python3.7/site-packages/nose/failure.py", line 39, in runTest ImportError: libgsl.so.23: cannot open shared object file: No such file or directory FAILED (errors=2) PyNEST tests: 2 Passed: 0 Skipped: 0 Failed: 2 --2-- Concerning GLS log : Use GSL : Yes (GSL 2.6) Includes : /usr/include Libraries : /usr/lib/libgsl.so;/usr/lib/libgslcblas.so