correct ulib location:

base/singularity:3.6.2

@@ -15,7 +15,7 @@ FROM debian:stretch
       ./mconfig && \
       make -C ./builddir && \
       make -C ./builddir install	
-  RUN wget https://git.km3net.de/common/jpp/raw/758d57dae93c9624670e2e9dde2aef5b5186d732/software/scripts/ulib.sh?inline=false -O /usr/local/bin/ulib.sh && chmod a+rx /usr/local/bin/ulib.sh
+  RUN wget http://sftp.km3net.de/singularity/ulib.sh -O /usr/local/bin/ulib.sh && chmod a+rx /usr/local/bin/ulib.sh
    	
 #Set the go environment 
    RUN echo '\
@@ -30,4 +30,5 @@ FROM debian:stretch
  source /usr/local/bin/ulib.sh\n\
  fi\n'\
      >> /etc/zsh/zshenv
+ SHELL ["/bin/zsh", "-c"]
  CMD ["/bin/zsh"]
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