JAliEn is the next generation ALICE Grid middleware that is going to be used in Run 3.
The software is already available in CVMFS and alidist and it can be used now.
See the migration guidelines and tutorial for more information.
Latest presentation on status of alien.py client can be seen here
The main AliEn web site is alien.web.cern.ch where you can find instructions on how to register to the ALICE VO , handle Grid certificates, manage VoBoxes, Storage Elements and more.
You can improve this documentation by editing files in the GitLab project