It is established that that contract, as defined by the Law, in
terms of binding to its parties, is the law of the contracting
parties, as long as it does not conflict in any of its clauses with
the jus cogens. However, sometimes compliance with work
customs may also be obligatory, even if it is not stipulated by
peremptory legal provisions. Accordingly, customary rules in work
shall be taken into account during the implementation of the
contract. Adherence to contract provisions may not lead to
exclusion and neglect of customs related to workmanship. For
example, we can refer to judicial activity sometimes, as
legislation is not the only legal source, and, therefore, the judge
or the arbitral tribunal may refer to legal custom to fill the gap
in the absence of legislative treatment of some or all of the
circumstances of the issue in question. This in addition to the
need to verify that the terms of the contract do not breach or
neglect customary issues applicable to
