I am trying to set multiple cookies with the same name on the gock response, but it always seems to only set the first cookie on the response object. Am I doing something wrong - is there a better way to set cookies? The mergeHeaders function appears to be the culprit. I have a solution and test here: https://github.com/steinfletcher/gock/commit/75ea39d311ffa5c435ffb9a015de2480c980ff55 Thanks