foo.js

  async $beforeInsert (queryContext) {
    await super.$beforeInsert(queryContext)
    validateStartDate(this)
    const trx = await Person.startTransaction();
    await this.validateAssignmentOverlap(this, trx)
    queryContext.resolveTransaction = trx;
     
  }

  async $afterInsert (queryContext) {
    await super.$afterInsert(queryContext)
    queryContext.resolveTransaction.commit();
  }

// MAKE SURE TO HANDLE ROLLBACK!~!