diff --git a/init/basics/ui.el b/init/basics/ui.el
index c0d4e13..f7add30 100644
--- a/init/basics/ui.el
+++ b/init/basics/ui.el
@@ -1,29 +1,34 @@
 ;;; ui.el --- Configure user interfaces. -*- lexical-binding: t; -*-
 
-;; Time-stamp: <2019-10-15T12:17:42+00:00>
+;; Time-stamp: <2019-11-09T17:19:20+00:00>
 
 ;;; Commentary:
-;; * neotree.
+;; * treemacs
 ;; * ivy + counsel.
 
 ;;; Code:
 
-;; Show directory tree in a window.
-(use-package neotree
-  :pin melpa                        ; <= 0.5.2 changes directory on file switch.
+;; Directory tree.
+(use-package treemacs
   :demand t
-  :after (all-the-icons)
 
   :custom
-  (neo-smart-open t)
-  (neo-show-updir-line t)           ; Disabled by doom-themes?
-  (neo-window-width 40)
-  (neo-show-hidden-files t)
-  (neo-theme 'icons)
+  (treemacs-project-follow-cleanup t)
 
   :bind
-  ("<f8>" . neotree-show)
-  ("C-<f8>" . neotree-hide)
+  ("<f8>" . treemacs-select-window)                     ; Focus treemacs.
+  ("C-<f8>" . treemacs)                                 ; Toggle treemacs.
+  ("M-<f8>" . treemacs-add-and-display-current-project) ; Add current project.
+  (:map treemacs-mode-map
+        ("<mouse-1>" . treemacs-single-click-expand-action))
+  )
+
+(use-package treemacs-projectile
+  :after (treemacs projectile)
+  )
+
+(use-package treemacs-magit
+  :after (treemacs magit)
   )
 
 ;; Completion in many Emacs commands.
diff --git a/init/programming/common.el b/init/programming/common.el
index b11296c..4464a32 100644
--- a/init/programming/common.el
+++ b/init/programming/common.el
@@ -1,6 +1,6 @@
 ;;; common.el --- Common programming settings. -*- lexical-binding: t; -*-
 
-;; Time-stamp: <2019-10-14T15:06:34+00:00>
+;; Time-stamp: <2019-11-09T17:48:35+00:00>
 
 ;;; Commentary:
 
@@ -100,16 +100,29 @@
 ;; Automatic project management.
 (unless slow-computer
   (use-package projectile
-    :after (neotree ivy)
+    :after (treemacs ivy)
 
     :init
     (defvar my/cmake-compile-command    ; cmake command for compiling with 1
       (concat "cmake --build . -- -j"   ; core less than available.
               (substring (shell-command-to-string "nproc --ignore=1") 0 -1)))
 
+    (defun my/switch-project ()
+      "Add project to treemacs."
+      (treemacs-add-and-display-current-project)
+      (treemacs-collapse-other-projects))
+
+    (defun my/projectile-kill-buffers ()
+      "Kill project buffers and remove project from treemacs."
+      (interactive)
+      (projectile-kill-buffers)
+        (let ((current-prefix-arg (projectile-project-name)))
+          (treemacs-remove-project-from-workspace)))
+
     :custom
     (projectile-project-compilation-dir "build")
-    (projectile-switch-project-action 'neotree-projectile-action)
+    ;; (projectile-switch-project-action 'neotree-projectile-action)
+    (projectile-switch-project-action 'my/switch-project)
     (projectile-project-configure-cmd
      "cmake -DCMAKE_BUILD_TYPE=Debug -DCMAKE_EXPORT_COMPILE_COMMANDS=ON \
 -GUnix\\ Makefiles ..")
@@ -126,6 +139,8 @@
 
     :bind
     ("C-c p" . 'projectile-command-map)
+    (:map projectile-command-map
+          ("k" . 'my/projectile-kill-buffers))
     )
   ) ; unless slow-computer.