It works like a charme!
I installed it under Debian Buster accordingly to your advise, and it installed and compiled without any issue.
Tested the function afterwards with my 2 U2 (shame on me) and it works great.
Thanks for the feedback.
EDIT: but it did not show the worker or hashrate under user/btcaddress

so there is something to look after.
That will be because the proxy is mining at the pool diff, 10k, so your hashrate is too small to show up.