Pipeline-style authoring

flowchart LR
    START([START])
    END([END])

    START ~~~ workflow
    workflow ~~~ END

    subgraph workflow [" "]
        step_one["Step one"]
        step_three["Step three"]
        step_two["Step two"]
        step_one -.-> step_two
        step_two -.-> step_three
    end

    START --> step_one
    step_three --> END

    classDef gated stroke:#9333ea,stroke-width:2px