src/Query/Builder.php
public function orderBy($field, $order = null)
    {
        $this->scope->orderBy[] = Parser::orderBy($field, $order);
        return $this;
    }
public function orderBy($field, $order = null)
    {
        $this->scope->orderBy[] = Parser::orderBy($field, $order);
        return $this;
    }
Add "Order by" clause to the query.

@param  string  $field
@param  string  $order
@return $this