Circular dependency calls don't work

[thoughtarray]

Something like this:

curl 'localhost:5000?chain=bar,baz,bar'

doesn't work.

[thoughtarray]

Turns out this isn't a bug per se. The development server that Flask uses is from from werkzeug.serving import run_simple. It seems to be a fully blocking http server. If test app is to be non-blocking, a different server than the dev server is required.