Keel configuration to work behind a reverse proxy

[gmej]

I could not find any documentation about how to make Keel work behind a reverse proxy.
Let's say I want to run Keel on this URL: https://my_url.tld/prefix1/. I have not see anyway to tell keel to construct all the URLs based on that prefix, and I cannot make webhooks to work because the URL are constructed as https://my_url.tld/logo.png instead of https://my_url.tld/prefix1/logo.png