def check(operations, loud=False):
    if not CHECKERS:
        load_checkers()
    roll_call = []
    everything_ok = True
    if loud and operations:
        title = "Preflyt Checklist"
        sys.stderr.write("{}\n{}\n".format(title, "=" * len(title)))
    for operation in operations:
        if operation.get('checker') not in CHECKERS:
            raise CheckerNotFoundError(operation)
        checker_cls = CHECKERS[operation['checker']]
        args = {k: v for k, v in operation.items() if k != 'checker'}
        checker = checker_cls(**args)
        success, message = checker.check()
        if not success:
            everything_ok = False
        roll_call.append({"check": operation, "success": success, "message": message})
        if loud:
            sys.stderr.write(" {}\n".format(pformat_check(success, operation, message)))
    return everything_ok, roll_call