[pfitzsimmons]

One approach is to start documenting how much of your time is spent either a) manually testing changes because you have no automated tests b) debugging, fixing bugs, and patching messed up data due to bugs that easily could have been caught by tests. I find that investing in basic acceptance tests pays itself off very quickly. Good tests allow you to iterate on your early product much faster, because you can actually make changes without breaking things for your early users. If you can document the wasted time, maybe you can convince him of the benefit.