Add undo-tree package

pkg/base.el

@@ -155,6 +155,18 @@
 (keyfreq-mode t)
 (keyfreq-autosave-mode t)
 
+;;;;;;;;;;;;;;;;; Use more advanced undo options
+(use-package undo-tree
+  :defer t
+  :ensure t
+  :config (setq-default
+           ;; Show diff
+           undo-tree-visualizer-diff t
+           ;; Show timestamps
+           undo-tree-visualizer-timestamps t))
+
+(global-undo-tree-mode t)
+
 ;;;;;;;;;;;;;;;;; Show hints about key combinations
 (use-package which-key
   :defer t

pkg/hydra.el

@@ -43,7 +43,7 @@ _d_: Deft                       _c_: Invalidate cache
 ^^^^^^^^-----------------------------------------------------------------------
 _c_: Comment line      _y_: Yasnippet
 _r_: Regex replace     _m_: Company
-_i_: Indent region
+_i_: Indent region     _u_: Undo tree
 _a_: Align regexp
 _e_: Eval region
 _s_: Swiper
@@ -57,6 +57,7 @@ _s_: Swiper
     ("e"  eval-region)
     ("s"  swiper)
 
+    ("u"  undo-tree-visualize)
     ("y"  company-yasnippet)
     ("m"  company-complete))