How do I modularize the order of execution and/or dependency relationships between jobs in a CircleCI orb?

Question

Our CircleCI orb defines two jobs - A and B.

Our customers use, and are expected to use the jobs in a specific way.

i.e., the customers are expected to define a job C, and invoke A and B such that A runs before C and B runs after C.

Currently, our customers enforce that using the 'require' key.

Is there a way to:

1. abstract this detail (the order of job exec) away from our customers?
2. ideally, require that the jobs can only be run in that exact order.

This is an actual example of a workflow our customer is using.

  customers_workflow:
    jobs:
      - our-orb/a:
          filters:
            branches:
              only: master
      - c:
          requires: [our-orb/a]
          filters:
            branches:
              only: master
      - our-orb/b:
          requires: [c]
          filters:
            branches:
              only: master

Answer 1

The potential only solution I've come up with so far is requiring c to be a shell script "c.sh" instead of a CircleCI job and combining jobs a and b into one job ab, which runs the commands in a, the shell script c.sh from the invoking repo and b consecutively.