HubSpot chief financial officer John Kinzer is stepping down from his role at the end of the year, the company announced on Tuesday. The company said it will start looking for a new CFO and Kinzer "will work to ensure a smooth transition of his duties." Kinzer, who was previously CFO at Cape Cod-based BackOffice Associates, led HubSpot through one of the most successful initial public offerings in the recent history of the Massachusetts tech industry.