The best way to set keybindings has been changed, from define-key and global-set-key to keymap-set and keymap-global-set.

Some examples:

  (keymap-global-set "<remap> <upcase-word>" #'upcase-dwim)
  (keymap-set icomplete-minibuffer-map "TAB" #'icomplete-force-complete)

You can also use package.el to install packages from version control now, check the package-vc-selected-packages variable.