add more backends, fix bug

Created by  7MWJfjv9BDues7qKhJuZJxfJqnJTsGegrzX3gqKCjiEi  on December 5, 2021
CVFRQKAVAUAYM53YLRGOOPYGVWRWIC7T5F366QVBDCM2RRCI66GAC
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