Access Mailcathecher via subfolder

Hi, I would like to use more dockerized services via same domain and served by nginx. I have few services with apache, where I solved this with:

FROM dehy/adminer
RUN ln -s /var/www/html /var/www/html/adminer

Now adminer is accessible by dockerurl and also dockerurl/adminer
I would like to do the same with jgiannuzzi/mailcatcher , which is not based on apache. Can you give me a hand? Thanks.