Engineering at architect altitude.

The lifecycle is enforced on the server: 28 states with forward, backward, on-hold and exception moves. Backward moves and exceptions require a reason, and every transition is audited. AI output is advisory only, and personal fields are redacted before any model call.

    if current in EXCEPTION_STATUSES:
        return frozenset({LeadStatus.CLOSED})
    if current is LeadStatus.ON_HOLD:
        allowed = {LeadStatus.CLOSED}
        if held_from is not None:
            allowed.add(held_from)
        return frozenset(allowed)

    allowed = set(EXCEPTION_STATUSES)
    if current in PRIMARY_PATH:
        index = PRIMARY_PATH.index(current)
        if index + 1 < len(PRIMARY_PATH):
            allowed.add(PRIMARY_PATH[index + 1])
    allowed.update(_FORWARD_EXTRA.get(current, frozenset()))
    backward = _backward_target(current)
    if backward is not None:
        allowed.add(backward)
    if current in _HOLD_ELIGIBLE:
        allowed.add(LeadStatus.ON_HOLD)
    return frozenset(allowed)

Selected source excerpt · inspected September 2026 · no application data