Ideally you should be including the test automation (both unit and acceptance tests (with the latter becoming part of your regression suite) as a part of what needs to be in place for an item to be DONE. It's all part of being ready to ship at the end of any sprint.

That might mean you'll have to get some help from your teammates to complete that automation before items can be accepted as done, since in my experience a 4:1 ratio places a lot of load on the 'tester'. If you wait to try and do them later 'when there is time' you'll likely fall further and further behind because often there just isn't much time for that.

Then get your CI system setup so that the regression tests run on a regular basis (I'd recommend nightly)

BTW: a great definition of DONE I heard the other day was "never have to think about that story again"

See this great talk by Ken Schwaber (in three parts) that covers a lot of this and makes some very important points.

Ideally, you should be including the test automation (both unit and acceptance tests (with the latter becoming part of your regression suite) as a part of what needs to be in place for an item to be DONE. It's all part of being ready to ship at the end of any sprint.

That might mean you'll have to get some help from your teammates to complete that automation before items can be accepted as done, since in my experience a 4:1 ratio places a lot of load on the 'tester'. If you wait to try and do them later 'when there is time' you'll likely fall further and further behind because often there just isn't much time for that.

Then get your CI system setup so that the regression tests run on a regular basis (I'd recommend nightly)

BTW: a great definition of DONE I heard the other day was "never have to think about that story again"

See this great talk by Ken Schwaber (in three parts) that covers a lot of this and makes some very important points.