Installed dependencies like so:
sudo apt-get install cmake libvala-0.30-dev valac-0.30 libwebkitgtk-3.0-dev libgranite-dev libcanberra-dev libsqlite3-dev libgmime-2.6-dev libsecret-1-dev libgcr-3-dev libgirepository1.0-dev valadoc
Then tried to build the new pantheon-mail but getting stuck at this error
[ 76%] Generating .pantheon-mail.stamp /usr/local/src/pantheon-mail/src/client/conversation-viewer/ConversationWidget.vala:98.13-98.34: error: The type name `Granite.Widgets.Avatar' could not be found private Granite.Widgets.Avatar avatar; ^^^^^^^^^^^^^^^^^^^^^^ Compilation failed: 1 error(s), 0 warning(s) make[2]: * [src/.pantheon-mail.stamp] Error 1 make[1]: * [src/CMakeFiles/pantheon-mail.dir/all] Error 2 make: *** [all] Error 2
Not sure how to proceed, any build tips appreciated