How to: Compose-specific details
In case if rules set as a part of docker compose environment, destination with the regex group will conflict with compose syntax. I.e. attempt to use `https://api.example.com/$1` in compose environment will fail due to a syntax error. The standard solution here is to "escape" `$` sign by replacing it with `$$`, i.e. `https://api.example.com/$$1`. This substitution supported by docker compose and has nothing to do with reproxy itself. Another way is to use `@` instead of `$` which is supported on reproxy level, i.e. `https://api.example.com/@1`_