Attorney General Maura Healey is investigating the performance of CGI, the Canadian software developer that built the failed website for the Massachusetts Health Connector, continuing a review started by her predecessor.

Healey’s investigation adds to other inquiries into what led to the disastrous 2013 rollout of new software for the Connector, a debacle that continues to affect people buying health insurance on their own.

Governor Charlie Baker’s administration acknowledged earlier this month that it had received a subpoena in January from the US attorney’s office, seeking Connector documents dating to 2010. But the administration provided no details, and US Attorney Carmen Ortiz declined to confirm or deny that an investigation was underway.

Meanwhile, the University of Massachusetts Medical School, which initially led technology development for the website, said the school had received a subpoena from the US attorney as well as requests for documents from the state attorney general and the inspector general of the US Department of Health and Human Services.