Defining routes disables default route?

[concentrateddon]

This may be by design; trying to confirm.

If I boot up a minimal MWS2, it serves /index.html just fine. But if I start defining routes, /index.html no longer serves—it just seems to ignore the request. It also doesn't serve / (which should be index.html as well).

Is it intended that, by defining routes, I'm then expected to also define the default route myself?