Cannot SIGTERM chaussette

[arthurzenika]

Follow up of circus-tent/circus#986 when launching chaussette from the command line as follows :

/home/arthur/.virtualenvs/app/bin/chaussette --backend waitress --log-level debug --log-output - --use-reloader wsgi.app

I cannot CTRL-C it of kill SIGTERM or even kill -9 (even as root).

Versions :

chaussette (1.3.0)
circus (0.13.0)

Trying out the same options with the hello_app, works ok :

$ chaussette  --backend waitress --log-level debug --log-output - --use-reloader 
 * Restarting with stat
2016-06-02 18:38:23 [12294] [INFO] Application is <function hello_app at 0x7fc53c386230>
2016-06-02 18:38:23 [12294] [INFO] Serving on localhost:8080
2016-06-02 18:38:23 [12294] [INFO] Using <class 'chaussette.backend._waitress.Server'> as a backend
^C
$

Any tips on what types of errors I could have in my wsgi app that would lead to such a problem ?