For Hg Mercurial you make sure the configuration file allows the web service to bind to all available network interfaces
web Web interface configuration. The settings in this section apply to both the builtin webserver (started by hg serve) and the script you run through a webserver (hgweb.cgi and the derivatives for FastCGI and WSGI). ... The full set of options is: address Interface address to bind to. Default is all.