diff --git a/engine/dev.sh b/engine/dev.sh
index 4f6cd20..909ea2e 100755
--- a/engine/dev.sh
+++ b/engine/dev.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env zsh
 
+cd "$(git rev-parse --show-toplevel)" || exit 1
+source ./engine/envvars.sh
+
 ## colors for tput
 # black=0
 red=1
@@ -13,8 +16,11 @@ green() { printf "$(tput setaf $green)%s$(tput sgr0)" "$*" }
 yellow() { printf "$(tput setaf $yellow)%s$(tput sgr0)" "$*" }
 blue() { printf "$(tput setaf $blue)%s$(tput sgr0)" "$*" }
 
-tee >(lorri watch | sed 's/^/[lorri] /' ) \
-  >(./engine/serve.sh | sed 's/^/[http] /') \
-  >(./engine/auto-build.sh | sed 's/^/[make] /') \
-  >(sleep 1 && open 'http://127.0.0.1:3000')
+pipegreen() {while read line; do green $line; done}
+pipeyellow() {while read line; do yellow $line; done}
+pipeblue() {while read line; do blue $line; done}
 
+tee >(lorri watch | sed 's/^/[lorri] /' | pipegreen ) \
+  >(./engine/serve.sh | sed 's/^/[http] /' | pipeyellow) \
+  >(./engine/auto-build.sh | sed 's/^/[make] /' | pipeblue) \
+  >(sleep 1 && open 'http://127.0.0.1:3000')
diff --git a/engine/optim-img.sh b/engine/optim-img.sh
index 62b4eb3..b48cff4 100755
--- a/engine/optim-img.sh
+++ b/engine/optim-img.sh
@@ -14,9 +14,11 @@ before=$(sizeof $src)
 
 if [[ "${src:e}" == "gif" ]]; then
   after=$(sizeof $dst)
+  dest=$dst
 else
   cwebp "$dst" -quiet -o "$dst.webp"
   after=$(sizeof $dst.webp)
+  dest=$dst.webp
 fi
 
 
diff --git a/src/posts/0021-ia-writer-clone-within-doom-emacs/doom-zen-writer-theme.el b/src/posts/0021-ia-writer-clone-within-doom-emacs/doom-zen-writer-theme.el
new file mode 100644
index 0000000..2e22ce4
--- /dev/null
+++ b/src/posts/0021-ia-writer-clone-within-doom-emacs/doom-zen-writer-theme.el
@@ -0,0 +1,154 @@
+;;; doom-zen-writer-theme.el --- -*- lexical-binding: t; no-byte-compile: t; -*-
+;;
+;; Author: Yann Esposito <https://github.com/yogsototh>
+;; Created: October 24, 2021
+;; Version: 1.0.0
+;; Keywords: custom themes, faces
+;; Homepage: https://github.com/hlissner/emacs-doom-themes
+;; Package-Requires: ((emacs "25.1") (cl-lib "0.5") (doom-themes "2.2.1"))
+;;
+;;; Code:
+
+(require 'doom-themes)
+
+;;
+;;; Variables
+
+(defgroup doom-plain-theme nil
+  "Options for the `doom-plain' theme."
+  :group 'doom-themes)
+
+(defcustom doom-plain-padded-modeline doom-themes-padded-modeline
+  "If non-nil, adds a 4px padding to the mode-line.
+Can be an integer to determine the exact padding."
+  :group 'doom-plain-theme
+  :type '(or integer boolean))
+
+
+;;
+;;; Theme definition
+
+(def-doom-theme doom-zen-writer
+  "Theme inspired by gko's plain."
+
+  ;; name      default/256/16
+  ((bg         '("#ffffff"))
+   (bg-alt     '("#eaecea"))
+   (base0      '("#969896"))
+   (base1      '("#f1f3f5"))
+   (base2      '("#606666"))
+   (base3      '("#cccccc"))
+   (base4      '("#e7e7e7"))
+   (base5      '("#a5a8a6"))
+   (base6      '("#fafafa"))
+   (base7      '("#dfdfdf"))
+   (base8      '("#fafafa"))
+   (fg         '("#969896"))
+   (fg-alt     (doom-lighten fg 0.15))
+
+   (grey       fg)
+   (red        fg)
+   (blue       fg)
+   (dark-blue  fg)
+   (orange     fg)
+   (green      fg)
+   (teal       fg)
+   (yellow     fg)
+   (magenta    fg)
+   (violet     fg)
+   (cyan       fg)
+   (dark-cyan  fg)
+
+   ;; face categories -- required for all themes
+   (highlight      base2)
+   (vertical-bar   base5)
+   (selection      base1)
+   (builtin        base0)
+   (comments       base5)
+   (doc-comments   base5)
+   (constants      base0)
+   (functions      fg)
+   (keywords       fg)
+   (methods        fg)
+   (operators      fg)
+   (type           fg)
+   (strings        base0)
+   (variables      base0)
+   (numbers        base0)
+   (region         base4)
+   (error          (doom-blend fg "#ff0000" 0.4))
+   (warning        base2)
+   (success        green)
+   (vc-modified    base5)
+   (vc-added       (doom-lighten fg 0.7))
+   (vc-deleted     base2)
+
+   ;; custom categories
+   (-modeline-pad
+    (when doom-plain-padded-modeline
+      (if (integerp doom-plain-padded-modeline) doom-plain-padded-modeline 4)))
+
+   (modeline-bg              (doom-darken bg-alt 0.15))
+   (modeline-bg-alt          (doom-darken bg-alt 0.1))
+   (modeline-bg-inactive     (doom-darken bg-alt 0.1))
+   (modeline-bg-inactive-alt bg-alt)
+   (modeline-fg              fg)
+   (modeline-fg-alt          (doom-darken modeline-bg-inactive 0.35)))
+
+  ;;;; Base theme face overrides
+  ((error   :underline `(:style wave :color ,error))
+   (warning :underline `(:style wave :color ,warning))
+   (hl-sentence :foreground "#000000" :background bg)
+   ((font-lock-constant-face &override)      :slant 'italic)
+   ((font-lock-comment-face &override)       :slant 'italic)
+   ((font-lock-function-name-face &override) :slant 'italic)
+   ((font-lock-type-face &override)          :slant 'italic)
+   (hl-line :background base8)
+   ((line-number &override) :foreground base3)
+   ((line-number-current-line &override) :foreground base2)
+   (mode-line
+    :background modeline-bg :foreground modeline-fg
+    :box (if -modeline-pad `(:line-width ,-modeline-pad :color ,modeline-bg)))
+   (mode-line-inactive
+    :background modeline-bg-inactive :foreground modeline-fg-alt
+    :box (if -modeline-pad `(:line-width ,-modeline-pad :color ,modeline-bg-inactive)))
+   (mode-line-emphasis :foreground highlight)
+
+   ;;;; doom-modeline
+   (doom-modeline-bar :background modeline-bg)
+   (doom-modeline-bar-inactive :inherit 'doom-modeline-bar)
+   (doom-modeline-project-dir :foreground fg)
+   (doom-modeline-buffer-file :foreground fg)
+   (doom-modeline-buffer-modified :weight 'bold :foreground "#000000")
+   (doom-modeline-panel :inherit 'mode-line-highlight :background base3 :foreground fg)
+   ;;;; ivy
+   (ivy-posframe :background bg-alt)
+   ;;;; magit
+   ((magit-diff-added-highlight &override)   :foreground fg :background (doom-blend vc-added bg 0.3))
+   ((magit-diff-removed &override)           :foreground (doom-lighten fg 0.4) :background (doom-blend vc-deleted bg 0.1))
+   ((magit-diff-removed-highlight &override) :foreground fg :background (doom-blend vc-deleted bg 0.22))
+   ;;;; lsp-mode
+   (lsp-headerline-breadcrumb-symbols-face :foreground keywords :weight 'bold)
+   ;;;; outline <built-in>
+   (outline-1 :slant 'italic :foreground fg-alt)
+   (outline-2 :inherit 'outline-1 :foreground base2)
+   (outline-3 :inherit 'outline-2)
+   (outline-4 :inherit 'outline-3)
+   (outline-5 :inherit 'outline-4)
+   (outline-6 :inherit 'outline-5)
+   (outline-7 :inherit 'outline-6)
+   (outline-8 :inherit 'outline-7)
+   ;;;; org <built-in>
+   ((org-block &override) :background bg-alt)
+   ((org-block-begin-line &override) :foreground base5)
+   ;;;; solaire-mode
+   (solaire-mode-line-face
+    :inherit 'mode-line
+    :background modeline-bg-alt
+    :box (if -modeline-pad `(:line-width ,-modeline-pad :color ,modeline-bg-alt)))
+   (solaire-mode-line-inactive-face
+    :inherit 'mode-line-inactive
+    :background modeline-bg-inactive-alt
+    :box (if -modeline-pad `(:line-width ,-modeline-pad :color ,modeline-bg-inactive-alt)))))
+
+;;; doom-plain-theme.el ends here
diff --git a/src/posts/0021-ia-writer-clone-within-doom-emacs/index.org b/src/posts/0021-ia-writer-clone-within-doom-emacs/index.org
new file mode 100644
index 0000000..2c39b03
--- /dev/null
+++ b/src/posts/0021-ia-writer-clone-within-doom-emacs/index.org
@@ -0,0 +1,342 @@
+#+title: iA writer clone within doom-emacs
+#+description:
+#+keywords: emacs org-mode
+#+author: Yann Esposito
+#+email: yann@esposito.host
+#+date: [2021-10-24 Sun]
+#+lang: en
+#+options: auto-id:t
+#+startup: showeverything
+
+So I played with tweaking my emacs configuration again.
+I think I made something worth to be shared.
+I wanted to have the same effect than in iA writer within emacs.
+And I just reached this.
+
+So the effect I am looking to achieve can be seen in this video.
+
+#+name: demo video
+#+begin_export html
+<video src="./zen-writer-demo.mov" width="100%" controls autoplay>
+<a href="./zen-writer-demo.mov">zen-writer-demo video (7.2MB)</a>
+</video>
+#+end_export
+#+begin_comment
+=> ./zen-writer-demo.mov zen-writer-demo video (7.2MB)
+#+end_comment
+
+
+
+It highlight the current sentence (in black) while the rest of the text is
+gray.
+The main issue with the =hl-sentence= package alone is that it set a specific
+face to the current sentence, but does not affect the other text in the
+buffer.
+In fact to make it work as I would expect, you need to make the default
+color grey, and only set black for the highlighted text.
+
+Fortunately, I have recently created a personal theme close to that.
+I just created a new specific one.
+Everything is mostly "gray" except the font ~hl-sentence~ which is black.
+
+And that's it.
+So to make it all work I need.
+
+- a Gray theme,
+- the package ~hl-sentence~,
+- the ~writeroom~ package.
+
+So how to achieve that yourself?
+Here is how I do it.
+
+** The zen-writer theme
+:PROPERTIES:
+:CUSTOM_ID: the-zen-writer-theme
+:END:
+
+Download [[./doom-zen-writer-theme.el][Doom Zen-Writer theme]].
+This depend on doom-themes and here is the code of the theme.
+Just put it in you =~/.doom.d/themes= directory.
+
+** add this is your ~packages.el~
+:PROPERTIES:
+:CUSTOM_ID: add-this-is-your--packages-el-
+:END:
+
+#+begin_src elisp
+(package! hl-sentence
+  :pin "86ae38d3103bd20da5485cbdd59dfbd396c45ee4")
+#+end_src
+** Helpers
+:PROPERTIES:
+:CUSTOM_ID: helpers
+:END:
+
+You probably want to be able to put you out of this writing mode.
+Here is a [[file:zen-writer.el][zen-writer.el]] file that contain my keymaps and useful functions.
+
+Put it in you =~/.doom.d/= directory and in you =config.el=
+put
+
+#+begin_src emacs-lisp
+(load! "~/.doom.d/zen-writer.el")
+#+end_src
+
+And with this you should pass to zen mode with ~SPC y z z~.
+
+To make the un-zen works.
+You will need to have a ~y/auto-update-theme~ function that set your current theme.
+My function change the theme depending on the time of the day or the day of
+the week.
+
+So here it is for inspiration:
+
+#+begin_src emacs-lisp
+(defun y/auto-update-theme ()
+  "depending on time use different theme"
+  ;; very early => gruvbox-light, solarized-light, nord-light
+  (let* ((day-of-week (format-time-string "%a"))
+         (week-end? (or (equal "Sat" day-of-week)
+                        (equal "Sun" day-of-week)))
+         (hour (nth 2 (decode-time (current-time))))
+         (time-to-sleep? (or (> hour 22) (< hour 7)))
+
+         (theme (cond
+                 (time-to-sleep?  'doom-plain-dark)
+                 (week-end?       'doom-nord-light)
+                 ((<= 7 hour 8)   'doom-gruvbox-light)
+                 ((= 9 hour)      'doom-solarized-light)
+                 ((<= 10 hour 16) 'doom-solarized-white)
+                 ((<= 17 hour 18) 'doom-gruvbox-light)
+                 ((<= 19 hour 22) 'doom-oceanic-next))))
+    (when (not (equal doom-theme theme))
+      (setq doom-theme theme)
+      (load-theme doom-theme t))
+    ;; run that function again next hour
+    (run-at-time (format "%02d:%02d" (+ hour 1) 0) nil 'y/auto-update-theme)))
+#+end_src
+
+** Bonus
+:PROPERTIES:
+:CUSTOM_ID: bonus
+:END:
+
+I use Nerd Fonts and in particular the font `iMWritingDuoS` which is I
+think a clone of the iAWriter font.
+
+#+begin_src emacs-lisp
+(setq doom-variable-pitch-font
+      (font-spec :family "iMWritingDuoS Nerd Font" :size 12))
+#+end_src
+
+I hope you find this useful.
+I really like how it looks now.
+
+** Annex
+:PROPERTIES:
+:CUSTOM_ID: annex
+:END:
+
+The code source used in this article.
+
+*** zen-writer
+:PROPERTIES:
+:CUSTOM_ID: zen-writer
+:END:
+
+#+Name: zen-writer.el
+#+begin_src emacs-lisp :tangle zen-writer.el
+;;; zen-writer.el -*- lexical-binding: t; -*-
+
+(defun y/zen ()
+  (interactive)
+  (setq doom-theme 'doom-zen-writer)
+  (load-theme doom-theme t)
+  (hl-sentence-mode +1))
+
+(defun y/unzen ()
+  (interactive)
+  (y/auto-update-theme)
+  (hl-sentence-mode -1))
+
+(defun y/zen-full ()
+  (interactive)
+  (y/zen)
+  (toggle-frame-fullscreen)
+  (doom-big-font-mode +1))
+
+(defun y/unzen-full ()
+  (interactive)
+  (y/unzen)
+  (toggle-frame-fullscreen)
+  (doom-big-font-mode -1))
+
+(map! :leader
+      (:prefix ("y z" . "Zen Writer")
+       :desc "Full Zen Writer" "z" #'y/zen-full
+       :desc "un-Full Zen Writer" "u" #'y/unzen-full
+       :desc "Zen Writer" "t" #'y/zen
+       :desc "un-Zen Writer" "q" #'y/unzen))
+#+end_src
+
+*** zen-writer doom theme
+:PROPERTIES:
+:CUSTOM_ID: zen-writer-doom-theme
+:END:
+
+#+begin_src emacs-lisp :tangle doom-zen-writer-theme.el
+;;; doom-zen-writer-theme.el --- -*- lexical-binding: t; no-byte-compile: t; -*-
+;;
+;; Author: Yann Esposito <https://github.com/yogsototh>
+;; Created: October 24, 2021
+;; Version: 1.0.0
+;; Keywords: custom themes, faces
+;; Homepage: https://github.com/hlissner/emacs-doom-themes
+;; Package-Requires: ((emacs "25.1") (cl-lib "0.5") (doom-themes "2.2.1"))
+;;
+;;; Code:
+
+(require 'doom-themes)
+
+;;
+;;; Variables
+
+(defgroup doom-plain-theme nil
+  "Options for the `doom-plain' theme."
+  :group 'doom-themes)
+
+(defcustom doom-plain-padded-modeline doom-themes-padded-modeline
+  "If non-nil, adds a 4px padding to the mode-line.
+Can be an integer to determine the exact padding."
+  :group 'doom-plain-theme
+  :type '(or integer boolean))
+
+
+;;
+;;; Theme definition
+
+(def-doom-theme doom-zen-writer
+  "Theme inspired by gko's plain."
+
+  ;; name      default/256/16
+  ((bg         '("#ffffff"))
+   (bg-alt     '("#eaecea"))
+   (base0      '("#969896"))
+   (base1      '("#f1f3f5"))
+   (base2      '("#606666"))
+   (base3      '("#cccccc"))
+   (base4      '("#e7e7e7"))
+   (base5      '("#a5a8a6"))
+   (base6      '("#fafafa"))
+   (base7      '("#dfdfdf"))
+   (base8      '("#fafafa"))
+   (fg         '("#969896"))
+   (fg-alt     (doom-lighten fg 0.15))
+
+   (grey       fg)
+   (red        fg)
+   (blue       fg)
+   (dark-blue  fg)
+   (orange     fg)
+   (green      fg)
+   (teal       fg)
+   (yellow     fg)
+   (magenta    fg)
+   (violet     fg)
+   (cyan       fg)
+   (dark-cyan  fg)
+
+   ;; face categories -- required for all themes
+   (highlight      base2)
+   (vertical-bar   base5)
+   (selection      base1)
+   (builtin        base0)
+   (comments       base5)
+   (doc-comments   base5)
+   (constants      base0)
+   (functions      fg)
+   (keywords       fg)
+   (methods        fg)
+   (operators      fg)
+   (type           fg)
+   (strings        base0)
+   (variables      base0)
+   (numbers        base0)
+   (region         base4)
+   (error          (doom-blend fg "#ff0000" 0.4))
+   (warning        base2)
+   (success        green)
+   (vc-modified    base5)
+   (vc-added       (doom-lighten fg 0.7))
+   (vc-deleted     base2)
+
+   ;; custom categories
+   (-modeline-pad
+    (when doom-plain-padded-modeline
+      (if (integerp doom-plain-padded-modeline) doom-plain-padded-modeline 4)))
+
+   (modeline-bg              (doom-darken bg-alt 0.15))
+   (modeline-bg-alt          (doom-darken bg-alt 0.1))
+   (modeline-bg-inactive     (doom-darken bg-alt 0.1))
+   (modeline-bg-inactive-alt bg-alt)
+   (modeline-fg              fg)
+   (modeline-fg-alt          (doom-darken modeline-bg-inactive 0.35)))
+
+  ;;;; Base theme face overrides
+  ((error   :underline `(:style wave :color ,error))
+   (warning :underline `(:style wave :color ,warning))
+   (hl-sentence :foreground "#000000" :background bg)
+   ((font-lock-constant-face &override)      :slant 'italic)
+   ((font-lock-comment-face &override)       :slant 'italic)
+   ((font-lock-function-name-face &override) :slant 'italic)
+   ((font-lock-type-face &override)          :slant 'italic)
+   (hl-line :background base8)
+   ((line-number &override) :foreground base3)
+   ((line-number-current-line &override) :foreground base2)
+   (mode-line
+    :background modeline-bg :foreground modeline-fg
+    :box (if -modeline-pad `(:line-width ,-modeline-pad :color ,modeline-bg)))
+   (mode-line-inactive
+    :background modeline-bg-inactive :foreground modeline-fg-alt
+    :box (if -modeline-pad `(:line-width ,-modeline-pad :color ,modeline-bg-inactive)))
+   (mode-line-emphasis :foreground highlight)
+
+   ;;;; doom-modeline
+   (doom-modeline-bar :background modeline-bg)
+   (doom-modeline-bar-inactive :inherit 'doom-modeline-bar)
+   (doom-modeline-project-dir :foreground fg)
+   (doom-modeline-buffer-file :foreground fg)
+   (doom-modeline-buffer-modified :weight 'bold :foreground "#000000")
+   (doom-modeline-panel :inherit 'mode-line-highlight :background base3 :foreground fg)
+   ;;;; ivy
+   (ivy-posframe :background bg-alt)
+   ;;;; magit
+   ((magit-diff-added-highlight &override)   :foreground fg :background (doom-blend vc-added bg 0.3))
+   ((magit-diff-removed &override)           :foreground (doom-lighten fg 0.4) :background (doom-blend vc-deleted bg 0.1))
+   ((magit-diff-removed-highlight &override) :foreground fg :background (doom-blend vc-deleted bg 0.22))
+   ;;;; lsp-mode
+   (lsp-headerline-breadcrumb-symbols-face :foreground keywords :weight 'bold)
+   ;;;; outline <built-in>
+   (outline-1 :slant 'italic :foreground fg-alt)
+   (outline-2 :inherit 'outline-1 :foreground base2)
+   (outline-3 :inherit 'outline-2)
+   (outline-4 :inherit 'outline-3)
+   (outline-5 :inherit 'outline-4)
+   (outline-6 :inherit 'outline-5)
+   (outline-7 :inherit 'outline-6)
+   (outline-8 :inherit 'outline-7)
+   ;;;; org <built-in>
+   ((org-block &override) :background bg-alt)
+   ((org-block-begin-line &override) :foreground base5)
+   ;;;; solaire-mode
+   (solaire-mode-line-face
+    :inherit 'mode-line
+    :background modeline-bg-alt
+    :box (if -modeline-pad `(:line-width ,-modeline-pad :color ,modeline-bg-alt)))
+   (solaire-mode-line-inactive-face
+    :inherit 'mode-line-inactive
+    :background modeline-bg-inactive-alt
+    :box (if -modeline-pad `(:line-width ,-modeline-pad :color ,modeline-bg-inactive-alt)))))
+
+;;; doom-zen-writer-theme.el ends here
+#+end_src
diff --git a/src/posts/0021-ia-writer-clone-within-doom-emacs/zen-writer-demo.mov b/src/posts/0021-ia-writer-clone-within-doom-emacs/zen-writer-demo.mov
new file mode 100644
index 0000000..328c4a9
Binary files /dev/null and b/src/posts/0021-ia-writer-clone-within-doom-emacs/zen-writer-demo.mov differ
diff --git a/src/posts/0021-ia-writer-clone-within-doom-emacs/zen-writer.el b/src/posts/0021-ia-writer-clone-within-doom-emacs/zen-writer.el
new file mode 100644
index 0000000..84a1516
--- /dev/null
+++ b/src/posts/0021-ia-writer-clone-within-doom-emacs/zen-writer.el
@@ -0,0 +1,31 @@
+;;; zen-writer.el -*- lexical-binding: t; -*-
+
+(defun y/zen ()
+  (interactive)
+  (setq doom-theme 'doom-zen-writer)
+  (load-theme doom-theme t)
+  (hl-sentence-mode +1))
+
+(defun y/unzen ()
+  (interactive)
+  (y/auto-update-theme)
+  (hl-sentence-mode -1))
+
+(defun y/zen-full ()
+  (interactive)
+  (y/zen)
+  (toggle-frame-fullscreen)
+  (doom-big-font-mode +1))
+
+(defun y/unzen-full ()
+  (interactive)
+  (y/unzen)
+  (toggle-frame-fullscreen)
+  (doom-big-font-mode -1))
+
+(map! :leader
+      (:prefix ("y z" . "Zen Writer")
+       :desc "Full Zen Writer" "z" #'y/zen-full
+       :desc "un-Full Zen Writer" "u" #'y/unzen-full
+       :desc "Zen Writer" "t" #'y/zen
+       :desc "un-Zen Writer" "q" #'y/unzen))
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+#+title: My personal environment sync
+#+description:
+#+keywords: programming
+#+author: Yann Esposito
+#+email: yann@esposito.host
+#+date: [2021-10-30 Sat]
+#+lang: en
+#+options: auto-id:t
+#+startup: showeverything
+
+I have a quite specific system that I improved along the years to manage my
+local environment.
+Think about, binaries I expect to have in my shell, as well as
+configuration files for various utilities, and a few personal scripts.
+
+The notion of what is exactly my local environment is not perfectly defined.
+I expect every of my computers to behave slightly differently.
+Some are for work-only, some personal use only.
+
+For the things I want everywhere, I have a peculiar personal system.
+
+I use a personal script that depends on [[https://yadm.io][yadm]] and [[https://github.com/nix-community/home-manager][home-manager]].
+
+My script try to check if some files where updated and react accordingly:
+
+1. I download the dot-files changes via =yadm=.
+2. If my home-manager files changes, it will run ~home-manager switch~
+   ; if it fails, try to update nix channels then try again.
+3. If my doom emacs packages changed, it will run ~doom sync~
+4. If the script itself changed, it re-run the script after updating itself.
+
+If the script detect that I changed my emacs configuration, it runs ~doom
+sync~ or ~doom sync -u~.
+
+Here it is:
+
+#+begin_src bash
+#!/bin/bash
+
+### logs fn helpers
+
+## colors for tput
+# black=0
+red=1
+green=2
+yellow=3
+blue=4
+# magenta=5
+# cyan=6
+# white=7
+highpr() {
+    printf "$(tput setaf $green)→$(tput sgr0) $(tput bold)%-60s$(tput sgr0)" "$*"
+}
+ok() {
+    local txt="OK"
+    echo -e " [$(tput bold)$(tput setaf $green)${txt}$(tput sgr0)]" >&2
+}
+info() {
+    echo -e " [$(tput bold)$(tput setaf $blue)$*$(tput sgr0)]" >&2
+}
+warn() {
+    echo -e "$(tput bold)$(tput setaf $yellow)$*$(tput sgr0)" >&2
+}
+err() {
+    echo -e "$(tput bold)$(tput setaf $red)$*$(tput sgr0)" >&2
+}
+fail() {
+    err -e "\n[ERR] $*"
+    exit 1
+}
+
+highpr "check nix"
+if ! [ -x "$(command -v nix)" ]; then
+    echo
+    err "nix does not seem to be installed."
+    err "Install it from: https://nixos.org/nix/"
+    exit 1
+fi
+ok
+
+highpr "yadm fetch"
+yadm fetch --quiet  || fail "yadm fetch failed"
+ok
+
+# check the hash of a few files before doing yadm pull
+OLD_SYNC_ENV_ID=$(yadm rev-parse HEAD:bin/sync-env.sh)
+OLD_HOME_MANAGER_ID=$(yadm rev-parse HEAD:.config/nixpkgs/home.nix)
+OLD_DOOM_PACKAGES=$(yadm rev-parse HEAD:.doom.d/packages.el)
+OLD_DOOM_INIT=$(yadm rev-parse HEAD:.doom.d/init.el)
+
+highpr "yadm pull"
+yadm pull --quiet || fail "yadm pull failed"
+ok
+
+# check the hash of a few files after doing yadm pull
+NEW_SYNC_ENV_ID=$(yadm rev-parse HEAD:bin/sync-env.sh)
+NEW_HOME_MANAGER_ID=$(yadm rev-parse HEAD:.config/nixpkgs/home.nix)
+NEW_DOOM_PACKAGES=$(yadm rev-parse HEAD:.doom.d/packages.el)
+NEW_DOOM_INIT=$(yadm rev-parse HEAD:.doom.d/init.el)
+
+highpr "check sync-env diff"
+if ! [ "$OLD_SYNC_ENV_ID" = "$NEW_SYNC_ENV_ID" ]; then
+    warn " changed"
+    warn " Starting ~/bin/sync-env.sh again"
+    echo
+    ~/bin/sync-env.sh
+    exit $?
+fi
+ok
+
+if [ -f "$HOME/.yadm/files.gpg" ]; then
+  highpr "yadm decrypt"
+  yadm decrypt || fail "yadm decrypt failed"
+  ok
+fi
+
+highpr "home-manager"
+USERNAME_NIX_FILE="$HOME/.config/nixpkgs/username.nix"
+if [ ! -f  "$USERNAME_NIX_FILE" ]; then
+  echo "\"$USER\"" >> "$USERNAME_NIX_FILE"
+fi
+if ! [ "$OLD_HOME_MANAGER_ID" = "$NEW_HOME_MANAGER_ID" ]; then
+    echo
+    highpr "home-manager switch"
+    home-manager switch || \
+      ( nix-channel --update && home-manager switch ) || \
+      fail "home-manager switch failed"
+    ok
+else
+    info "skipped"
+fi
+
+highpr "doom-emacs"
+doompath="$HOME/.emacs.d/bin/doom"
+if ! [ "$OLD_DOOM_PACKAGES" = "$NEW_DOOM_PACKAGES" ] || \
+   ! [ "$OLD_DOOM_INIT"     = "$NEW_DOOM_INIT"  ]; then
+  if [[ -x $doompath ]]; then
+      echo
+      highpr "doom sync"
+      $doompath sync || fail "doom failed to sync"
+      ok
+  else
+     fail "Cannot find doom executable at $doompath";
+  fi
+else
+   info "skipped"
+fi
+#+end_src
+
+** Bootstrapping
+:PROPERTIES:
+:CUSTOM_ID: boostraping
+:END:
+
+Bootstrapping this system is always a nice problem to think about.
+It is smooth when everything is set but to bootstrap it I need binaries
+installed by this system...
+So...
+How to handle the dependency cycle correctly?
+
+To minimize the pain, I removed more and more bootstrapping dependencies.
+Now my almost single dependence for bootstrapping my environment is =nix=.
+I haven't initialized any machine for a long time now.
+The following should work.
+
+0. Use fish[fn:fish]  ~chsh /bin/fish~
+1. Install nix
+   ~curl -L https://nixos.org/nix/install | sh~
+2. Install home-manager
+   #+begin_src bash
+   nix-channel --add https://github.com/nix-community/home-manager/archive/release-21.05.tar.gz home-manager
+   nix-channel --update
+   export NIX_PATH=$HOME/.nix-defexpr/channels${NIX_PATH:+:}$NIX_PATH
+   nix-shell '<home-manager>' -A install
+   #+end_src
+3. Install and use ~yadm~
+   #+begin_src bash
+   nix-shell -p yadm
+   yadm boostrap
+   yadm remote set-url origin <url-to-my-dot-files-repo>
+   yadm pull
+   #+end_src
+4. Still in the =nix-shell= with =yadm= run ~~/bin/sync-env.sh~
+
+
+There is a risk that step 3 fail because I pin most of my packages in
+home-manager configuration, and it will try to install =yadm=. This can
+conflict with the =yadm= installed in the current =nix-shell=.
+So sometime I need to:
+
+1. Remove the line installing =yadm= in my home-manager configuration first
+2. run =home-manager sync=
+3. get out of the =nix-shell=,
+4. add =yadm= back in the =home-manager= config
+5. run =home-manager sync= again, but this time out of the =nix-shell=.
+6. Finally I can run my =~/bin/sync-env.sh= command.
+
+So this post will probably be useful as a personal note in the future.
+Because bootstrapping is generally not trivial.
+I will probably update this post if something is missing.
+
+[fn:fish] I use fish for interactive shell. I use ~zsh~ for quick dirty
+scripts (a lot better than bash), and I switch to [[https://hackage.haskell.org/package/turtle][turtle]] if I need to be
+serious about the script.