Symlink kirby folder

I have several kirby installations on one server with each its own kirby source.
I want to simplify the update process, so I tried to place the kirby folder outside the document root and symlink the kirby folder.

assets/
content/
.htaccess
index.php
kirby -> /srv/kirby/kirby-3.4.5/
site/

However thats not working.

The Panel assets cannot be installed properly. The directory "/srv/kirby/media" cannot be created

Is it possible?