version 3.0

Features / Improvements

Rails 4.2.x!
brand new content editing experience. AlohaEditor and TinyMCE were dropped an replaced by Wysihtml with a new system to edit the content and see the changes in live.
new caching system.
introduce layouts for pages. If an editor wants to create a page, he/she can choose among layouts defined by the developer of the site.
site dashboard tracking the activities of all the editors of a site.
the subject of the notification email sent when a content entry is created in the public site can be modified.
markdown editor for editable text elements in a page and text fields of a content entry.
allow defining url 301 redirections per site.
implement the color custom field for content entries.
support for MongoDB 3.0.
manage translations of the back-office via Transifex.
option to redirect domains to the first main domain.
new Locomotive Ruby API client lib named Coal.
developer tab per site describing how to use Wagon and the Restful API for the site.
protect a whole site by a password.
the editable_file liquid tag accepts now a resize option for resizing/cropping images.
the translate liquid tag supports interpolation and pluralization.

brand new UI/UX
the back-office UI relies on Bootstrap, the most popular and powerful HTML/CSS framework.
upgrade to the last versions of the main gems: Rails (4.2.5), Mongoid (5.0.1), Devise, SimpleForm, Carrierwave, ...etc.
do not rely on subdomains anymore for the multi-sites functionality. Format of the url for the back-office of a site: http://myengine/locomotive/.
the page rendering engine has been extracted to its own gem: Steam. Both Wagon and Engine uses Steam.
drop CanCan and replace it by Pundit
replace HAML by SLIM for the back-office views for performance

You can find most of them here: Github issues