What a battle to get a simple uwsgi app deployed to caprover!
In the end it came down to Nginx configuration:
Remove the http:// part from the $upstream e.g.
# set $upstream http://<%-s.localDomain%>:<%-s.containerHttpPort%>;
set $upstream <%-s.localDomain%>:<%-s.containerHttpPort%>;Instead of using proxy_pass, replace with uwsgi_pass and include the uwsgi params:
# proxy_pass $upstream;
uwsgi_pass $upstream;
include /etc/nginx/uwsgi_params;