The Mer Wiki now uses your Mer user account and password (create account on https://bugs.merproject.org/)
Contribution
From Mer Wiki
Contributing to packages
Initial setup
Mer uses the Gerrit code review system and has all packages in the Core stored within git repositories.
First thing you should do is to register yourself on the Mer Gerrit and assign yourself a username, in the following referred to as USERNAME. You can use a Google account or OpenID to authenticate yourself.