The Preview release of GNOME Builder introduced in GNOME 3.16 brings a long list of attractive features for developers, among which we can mention live diagnostics as you type for several programming languages, including C++, C, Vala, Python, Go, JavaScript, Ruby, JSON, and CSS, robust auto-indenters for Python, XML, and GNU C89, a beautiful new GtkSourceView-based theme and corresponding integrated source editor, neat Emacs and Vim emulation, support for multiple views.