Reorganise the links to other Modus projects in the README.md and clarify I am not endorsing anybody's views

Mention omarchy-modus-themes by Dhavan Vaidya in the README.md
Add support for log-view-marked face (Emacs 32)
2026-09-10 07:16:30 -04:00 · 2026-09-07 11:39:25 +03:00 · 2026-09-06 15:38:17 +03:00 · 2026-09-04 16:49:03 +03:00 · 2026-09-01 12:44:05 +03:00 · 2026-09-01 05:11:05 +03:00
14 changed files with 5317 additions and 2920 deletions
--- a/CHANGELOG.org
+++ b/CHANGELOG.org
@ -1,5 +1,5 @@
 #+TITLE: Change log of the Modus Themes for GNU Emacs
-#+AUTHOR: Protesilaos Stavrou
+#+AUTHOR: Protesilaos
 #+EMAIL: info@protesilaos.com
 #+OPTIONS: ':nil toc:nil num:nil author:nil email:nil

@ -15,6 +15,488 @@ For further details, please consult these additional resources:
 + Manual :: <https://protesilaos.com/emacs/modus-themes>
 + Screenshots :: <https://protesilaos.com/emacs/modus-themes-pictures>

+* 5.3.0 on 2026-06-21
+:PROPERTIES:
+:CUSTOM_ID: h:b4fa17a7-77a3-4e54-9af8-6a413b6b4e7c
+:END:
+
+The Modus themes are in a stable state. To my mind, they provide the
+best "default theme" experience across the 40+ original themes I have
+carefully designed.
+
+Modus is also a platform for making themes for Emacs. There are plenty
+of derivatives already. I am linking to them through the project's
+README.md and am always happy to mention more packages---just let me
+know.
+
+This version does not include many user-facing changes. Most of my
+work focused on making internal refinements.
+
+** Load the themes through the =early-init.el=
+:PROPERTIES:
+:CUSTOM_ID: h:4d80aeaa-e93f-4cca-a2b2-792700081ead
+:END:
+
+The Modus themes can now be loaded through the =early-init.el= file.
+The idea is to avoid the flash of light that occurs under certain
+conditions during startup.
+
+This feature is the result of several changes to helper functions,
+especially those contributing to the ~modus-themes-generate-palette~
+function that Modus derivatives may be relying on.
+
+Thanks to Steven Allen for an intermediate refinement in pull request
+194 and to Mike Olson for another relevant tweak in pull request 199:
+
+- <https://github.com/protesilaos/modus-themes/pull/194>
+- <https://github.com/protesilaos/modus-themes/pull/199>
+
+Steven's contribution no longer exists in the code base due to other
+changes I made, but was still useful at the time.
+
+Both changes are small, meaning that their authors do not need to
+assign copyright to the Free Software Foundation.
+
+Also thanks to Jacod "Jake" Gordon for reminding me to apply one of
+the new functions to the ~org-habit~ faces. This was done in issue
+197: <https://github.com/protesilaos/modus-themes/issues/197>.
+
+** The underline for widget fields has the correct colour
+:PROPERTIES:
+:CUSTOM_ID: h:c936a591-25ff-440d-88e8-e710da2c3f59
+:END:
+
+Relevant faces use the palette entry for =border= (invoke the command
+~modus-themes-preview-colors~ or ~modus-themes-preview-colors-current~
+to view the entries in a theme's palette).
+
+A popular package that makes use of =widget.el= widgets is ~notmuch~.
+
+Thanks to ukiran03 for the contribution, which was done in pull
+request 193: <https://github.com/protesilaos/modus-themes/pull/193>.
+The change is small, meaning that ukiran03 does not need to assign
+copyright to the Free Software Foundation.
+
+** A palette can now have a =bg-popup= entry
+:PROPERTIES:
+:CUSTOM_ID: h:bb9166ae-2424-4edf-8004-91e99ff8555a
+:END:
+
+This gives users and derivative themes the option to pick a suitable
+value for popup interfaces, such as those of the ~company~ and ~corfu~
+packages.
+
+Thanks to aikrahguzar for making this suggestion in issue 70 of my
+~ef-themes~ repository (the ~ef-themes~ are built on top of the
+~modus-themes~ since Modus version =5.0.0=, Ef version =2.0.0=):
+<https://github.com/protesilaos/ef-themes/issues/70>.
+
+** Support for faces or packages
+:PROPERTIES:
+:CUSTOM_ID: h:cb1de864-f749-46e6-a8c4-1b5c47a59aff
+:END:
+
+- ~lin~ by Protesilaos.
+- ~pulsar~ by Protesilaos.
+- ~institution-calendar~ by Protesilaos.
+- ~markdown-ts-mode~ by Rahul Martim Juliato and Stéphane Marks.
+- ~trust-manager~ by Eshel Yaron.
+- ~typst-ts-mode~ by Ziqi Yang. Thanks to Pranshu Sharma for
+  suggesting its inclusion in issue 208:
+  <https://github.com/protesilaos/modus-themes/issues/208>.
+- new ~elfeed~ faces since the maintenance of the project was assumed
+  by Daniel Mendler, Karthik Chikmagalur, and Ihor Radchenko. To this
+  end, thanks to Steven Allen for pull request 217 that added the
+ =elfeed-show-*= faces: <https://github.com/protesilaos/modus-themes/pull/217>
+
+** Internal refinements to the ~modus-themes-with-colors~ macro
+:PROPERTIES:
+:CUSTOM_ID: h:36d438e6-2779-4e34-b9ae-bb26503643ed
+:END:
+
+It now correctly handles the order of default palette colours and
+user-defined palette overrides. Thanks to JD Smith for the
+contribution in pull request 191: <https://github.com/protesilaos/modus-themes/pull/191>.
+
+The change is small, meaning that JD does not need to assign copyright
+to the Free Software Foundation.
+
+** The ~multiple-cursors~ are fine even when a bar is used
+:PROPERTIES:
+:CUSTOM_ID: h:d707af16-66c9-4520-bd96-129e7b0511dd
+:END:
+
+When the ~cursor-type~ is configured to be a =bar=, the fake cursors
+produced by the ~multiple-cursors~ package will still look right.
+Thanks to Elias Gabriel Perez for the change to the
+~mc/cursor-bar-face~ in pull request 213: <https://github.com/protesilaos/modus-themes/pull/213>.
+
+** The ~blink-matching-paren-offscreen~ is the same as ~show-paren-match~
+:PROPERTIES:
+:CUSTOM_ID: h:025061cd-ebdf-47bd-a596-9e8e9d6afa7d
+:END:
+
+This is for thematic consistency. Thanks to Troy Brown for suggesting
+this change in issue 209: <https://github.com/protesilaos/modus-themes/issues/209>.
+
+** Get ~vc-annotate~ look right
+:PROPERTIES:
+:CUSTOM_ID: h:73e5911d-fe08-43b4-b3d9-e5a79af447b0
+:END:
+
+The built-in ~vc-annotate~ command relies on a user option to read
+color values. We cannot handle this nicely at the theme level. Users
+need to write their own configuration like this:
+
+#+begin_src emacs-lisp
+(defun my-modus-vc-annotate (&rest _)
+  (modus-themes-with-colors
+    (setq vc-annotate-background-mode nil)
+    (setq vc-annotate-very-old-color fg-dim)
+    (setq vc-annotate-color-map
+          `(( 20. . ,red)
+            ( 40. . ,red-cooler)
+            ( 60. . ,red-warmer)
+            ( 80. . ,yellow-warmer)
+            (100. . ,yellow)
+            (120. . ,yellow-cooler)
+            (140. . ,green-warmer)
+            (160. . ,green)
+            (180. . ,green-cooler)
+            (200. . ,cyan-cooler)
+            (220. . ,cyan-warmer)
+            (240. . ,cyan)
+            (260. . ,blue-warmer)
+            (280. . ,blue)
+            (300. . ,blue-cooler)
+            (320. . ,blue-intense)
+            (340. . ,magenta-cooler)
+            (360. . ,fg-dim)))))
+
+(with-eval-after-load 'vc-annotate
+  (my-modus-vc-annotate)
+  (add-hook 'enable-theme-functions #'my-modus-vc-annotate))
+#+end_src
+
+[ The above code is relevant as of this writing. Though remember that
+  I do not keep older publications up-to-date. The only source of
+  truth is the manual of the Modus themes. ]
+
+** Two old user options are no longer needed
+:PROPERTIES:
+:CUSTOM_ID: h:39eb95f4-76b1-46b8-8f2e-245591c2ec03
+:END:
+
+The user options ~modus-themes-completions~ and ~modus-themes-prompts~
+are obsolete. They used to be relevant before the introduction of
+palette overrides.
+
+** Rewrote large parts of the manual
+:PROPERTIES:
+:CUSTOM_ID: h:73703b3a-ef75-4cc0-97ca-344f8d6812ba
+:END:
+
+I did it for clarity, but also to remove notes that were specific to
+older versions of Emacs.
+
+** Many new ERT tests for the project
+:PROPERTIES:
+:CUSTOM_ID: h:98134bb3-9eea-4fc2-9f21-bc619508de8a
+:END:
+
+I have written many tests. They do not cover every single function,
+though the plan is to do that eventually. These tests are important to
+ensure that Modus is a solid platform for making derivative themes.
+
+Much of this was done live: <https://protesilaos.com/codelog/2026-04-10-emacs-spontaneous-live-modus-themes/>.
+
+Thanks to Benjamin Kästner for a couple of tweaks to a relevant macro
+in the tests' file. This was done in pull request 212, with further
+changes by me: <https://github.com/protesilaos/modus-themes/pull/212>.
+
+** Links to projects related to Modus
+:PROPERTIES:
+:CUSTOM_ID: h:50301743-a109-4d96-83dd-3b8c7c6b90ed
+:END:
+
+In the README.md I now mention projects that are related to the Modus
+themes, such as derivative Emacs themes, but also ports for other
+editors.
+
+There is also a link to my ~modus-themes-exporter~ package, which I
+developed during a live stream:
+
+- <https://github.com/protesilaos/modus-themes-exporter>
+- <https://protesilaos.com/codelog/2026-04-13-emacs-live-develop-modus-themes-exporter-package/>
+
+** Git commits
+:PROPERTIES:
+:CUSTOM_ID: h:e869b1e6-5bc1-4d79-83cd-bb3f648c3ebf
+:END:
+
+#+begin_src
+git shortlog 5.2.0..5.3.0 --summary --numbered
+    123	Protesilaos
+     2	Benjamin Kästner
+     2	Steven Allen
+     1	Elias Gabriel Perez
+     1	JD Smith
+     1	Mike Olson
+     1	ukiran03
+#+end_src
+
+* 5.2.0 on 2025-12-31
+:PROPERTIES:
+:CUSTOM_ID: h:2c723b97-df07-4a3e-915f-b00f6647f74b
+:END:
+
+This version fixes some bugs, adds a new feature for those who want to
+derive a theme from Modus, and makes other small quality-of-life
+refinements.
+
+** The ~modus-themes-with-colors~ should work at all times
+:PROPERTIES:
+:CUSTOM_ID: h:fcf14029-fd5f-4404-8ff7-370fb742c00d
+:END:
+
+In the transition to version =5.0.0=, I inadvertently introduced
+regressions to the behaviour of the ~modus-themes-with-colors~ macro.
+This macro ~let~ binds the current theme's palette around arbitrary
+Elisp expressions, which allows users to access the named colours
+therein. In versions =5.0.0= and =5.1.0= the macro could not read
+variables defined outside its scope. Users needed to write an ~eval~
+around it, which I did not like. Now the macro should not require such
+workarounds: it basically is a ~let~ that should work as expected
+everywhere.
+
+This was fixed over a series of Git commits related to issue 170:
+<https://github.com/protesilaos/modus-themes/issues/170>. Thanks to
+Alexandr Semenov and realazy for reporting the problems and testing my
+revisions.
+
+** The ~modus-themes-generate-palette~ function to quickly get a palette
+:PROPERTIES:
+:CUSTOM_ID: h:6786fe0c-3853-4586-89d6-4f60b3828b1c
+:END:
+
+Users or package developers who want to create a theme on top of Modus
+can now get a kickstart by defining their palette with the help of the
+new ~modus-themes-generate-palette~ function. This function is meant
+to return a complete palette, given a list of basic colours. Users can
+thus experiment with their new theme while knowing that what they got
+contains all the definitions; definitions that they may then modify
+further (e.g. to define different semantic mappings than the defaults
+such as, for example, to have =(fg-heading-1 red-warmer)= instead of
+what originally is =(fg-heading-1 fg-main)=).
+
+I have written extensive documentation in the manual, which includes a
+complete example of a Solarized theme that is built on top of Modus.
+If you have any questions, you are welcome to contact me.
+
+** Convenience commands to select only dark or light themes
+:PROPERTIES:
+:CUSTOM_ID: h:deaebb75-129a-4ca2-8fd3-d29ae723474a
+:END:
+
+The commands ~modus-themes-select-dark~ and ~modus-themes-select-light~
+use minibuffer completion to load a theme. The completion candidates
+are filtered to only dark or light themes, respectively.
+
+This is effectively the same as calling the command ~modus-themes-select~
+with a prefix argument (=C-u= by default).
+
+Remember that we also have the commands ~modus-themes-load-random~,
+~modus-themes-load-random-dark~, and ~modus-themes-load-random-light~.
+Otherwise use the command ~modus-themes-rotate~.
+
+** Improved prompt for theme selection
+:PROPERTIES:
+:CUSTOM_ID: h:fcfe5599-9d12-46cf-8896-e45625aa7304
+:END:
+
+The minibuffer prompt used by the various Modus commands to select a
+theme now has a grouping function in place: it shows the current theme
+at the top and then all other themes grouped by their dark or light
+background. This makes it easier to find a relevant theme, especially
+if lots of them are present, such as when ~modus-themes-include-derivatives-mode~
+is enabled and relevant packages/themes are available (e.g. my
+~ef-themes~ and ~standard-themes~).
+
+** Semantic colours for =transient.el= (e.g. in Magit)
+:PROPERTIES:
+:CUSTOM_ID: h:9bee92ab-e082-4f66-b01c-892860c60a0c
+:END:
+
+The =transient.el= concept of "semantic colours" is now supported.
+This is used by default in Magit to denote the different types of
+keys, such as those that exit the transient, keep it active, move to
+another transient, and the like. Users who prefer the old style where
+all key bindings looked the same must customise the user option
+~transient-semantic-coloring~.
+
+Note that the deuteranopia- and tritanopia- optimised themes adapt
+gracefully to such "semantics", owning to relevant internal
+refinements I made. Those themes cannot rely on the full colour
+spectrum to communicate such nuances.
+
+** All ~hl-todo-mode~ faces use a bold weight if appropriate
+:PROPERTIES:
+:CUSTOM_ID: h:309dd08f-dc01-47f6-8e88-0558181e1bb8
+:END:
+
+When the user option ~modus-themes-bold-constructs~ is set to a
+non-~nil~ value, then all keywords that ~hl-todo-mode~ highlights will
+be rendered in a bold weight (technically, they inherit the ~bold~
+face). This is how we were doing it before until I undid it by
+mistake. Thanks to Dominik Schrempf for reporting the bug in issue
+177: <https://github.com/protesilaos/modus-themes/issues/177>.
+
+** Theme-sensitive colours for Gnus mail groups
+:PROPERTIES:
+:CUSTOM_ID: h:ea438d6c-2e3e-4427-86af-3d9590e260d3
+:END:
+
+The Gnus mail groups no longer have hardcoded colour values. They will
+look different depending on the current Modus theme.
+
+** Faces that set a =:box= attribute handle unspecified colours
+:PROPERTIES:
+:CUSTOM_ID: h:98c4f263-81ad-4bb2-85fc-af30b32584a2
+:END:
+
+I updated all faces that use a =:box= attribute to account for the
+scenario of a user writing palette overrides that unset the relevant
+colour. Thanks to JD Smith for reporting a bug along those lines in
+issue 9 of my ~standard-themes~ repository (they are derived from the
+~modus-themes~, hence the changes here):
+<https://github.com/protesilaos/standard-themes/issues/9>.
+
+** The ~calendar-today~ and ~org-date-selected~ faces are disambiguated
+:PROPERTIES:
+:CUSTOM_ID: h:c5c7ff66-0ed8-424c-8579-b84b776ad461
+:END:
+
+These two faces are no longer using the same styles. This is because
+they can appear in the same buffer. Thanks to Rudolf Adamkovič for
+discussing this with me in the context of the same change for my
+~doric-themes~ (issue 20 in doric-themes.git):
+<https://github.com/protesilaos/doric-themes/issues/20>.
+
+** The Modus "current theme" respects multiple enabled themes
+:PROPERTIES:
+:CUSTOM_ID: h:4c2abd1b-407a-4273-96d8-aba3bb42e0dc
+:END:
+
+The Modus concept of "current theme" respects the user's choice for
+multiple themes loaded at once. It will return the first Modus theme
+even if it is not at the front of the list.
+
+[ Emacs will load multiple themes by default, which leads to awkward
+  colour combinations, unless you know what you are doing---as such all
+  the Modus commands that load a theme will disable all others, subject
+  to the user option ~modus-themes-disable-other-themes~. ]
+
+Thanks to Pierre Téchoueyres for reporting the scenario where multiple
+other themes are loaded on top of a Modus theme. This was done in
+issue 182: <https://github.com/protesilaos/modus-themes/issues/182>.
+
+Also thanks to Pierre for covering another snippet that I had missed.
+This was done in pull request 184:
+<https://github.com/protesilaos/modus-themes/pull/184>.
+
+Pierre has assigned copyright to the Free Software Foundation.
+
+** Fixed symbol of inherited AUCTeX face
+:PROPERTIES:
+:CUSTOM_ID: h:4caebf48-2544-4367-ad35-61957f5f043b
+:END:
+
+There was a typo which caused an error. Thanks to Rudolf Adamkovič for
+the patch and also for providing a relevant unit test. This was done
+in pull request 188: <https://github.com/protesilaos/modus-themes/pull/188>.
+
+Rudolf has assigned copyright to the Free Software Foundation.
+
+** Miscellaneous
+:PROPERTIES:
+:CUSTOM_ID: h:738675ea-6f7b-47e5-907e-468b67ecd430
+:END:
+
+- Thanks to Basil L. Contovounesios for simplifying a couple of
+  expressions. This was done in pull request 190:
+  <https://github.com/protesilaos/modus-themes/pull/190>. Basil has
+  assigned copyright to the Free Software Foundation.
+
+- The faces of the built-in ~completion-preview-mode~ are now
+  supported. Thanks to Kevin Fleming for asking me about this in issue
+  178: <https://github.com/protesilaos/modus-themes/issues/178>.
+
+- Several faces that had a strike-through effect when they did not
+  really need it are revised to use a wavy underline instead. The idea
+  is to let the text be readable at all times, regardless of the
+  effective font family. With the strike-through effect, some fonts
+  completely obscure the underlying text.Thanks to Morgan Willcock for
+  discussing with me the use of the strike-through style in issue 169:
+  <https://github.com/protesilaos/modus-themes/issues/169>.
+
+- All ~symbol-overlay~ faces are unique, fixing a mistake I had done
+  before.
+
+- The ~org-dispatcher-highlight~, which is used to highlight the keys
+  of the Org export interface, now uses the appropriate foreground
+  colour and is always rendered in a bold weight.
+
+- The ~org-habit~ faces no longer call the function
+ ~readable-foreground-color~. This is because that function does not
+  work if the theme is loaded via the =early-init.el=. Thanks to
+  Gaston Cabotin for reporting the problem in issue 174:
+  <https://github.com/protesilaos/modus-themes/issues/174>.
+
+- The ~gnus-button~, which Gnus uses in all sorts of places to mark
+  some text as clickable, is styled with a less intense underline and
+  will no longer follow the style of links, including possible palette
+  overrides. This way, Gnus article buffers will not have visual
+  noise. Thanks to Morgan Willcock for discussing this with me in
+  issue 140: <https://github.com/protesilaos/modus-themes/issues/140>.
+
+* 5.1.0 on 2025-11-07
+:PROPERTIES:
+:CUSTOM_ID: h:86a4b45a-14e0-45f1-9625-969ad966b9ff
+:END:
+
+This version fixes a critical bug in the ~modus-themes-with-colors~
+macro. In short, it was not working as before or was not working at
+all. Now it should do the right thing.
+
+Thanks to Alexandr Semenov for reporting a relevant bug in issue 170
+and for helping me test the results: <https://github.com/protesilaos/modus-themes/issues/170>.
+
+Thanks to Stéphane Marks for testing some configurations with the
+latest stable Emacs version as well as with builds from emacs.git.
+This was done via a private channel and I am sharing this information
+with permission.
+
+Also thanks to Stefan Monnier for monitoring my commits as I was
+trying to refactor the ~modus-themes-with-colors~ macro. Some comments
+were posted on the emacs-devel mailing list, as well as a patch that I
+ended up applying and then reverting (check the commit log for the
+technicalities): <https://lists.gnu.org/archive/html/emacs-devel/2025-11/msg00114.html>.
+
+Apologies to everyone for the inconvenience! This was a tricky bug.
+The good thing is that it compelled me to improve several parts of the
+code.
+
+This version also includes a clarification in the manual about
+building a theme on top of Modus:
+
+- Web page :: Visit <https://protesilaos.com/emacs/modus-themes#h:86eb375b-9be4-43ce-879a-0686a524a63b>.
+- Info manual :: Evaluate ~(info "(modus-themes) Build on top of the Modus themes")~.
+
+In short, it mentions that a theme exists in an appropriately named
+file that is part of the ~custom-theme-load-path~. Thanks to Ashton
+Wiersdorf for asking a related question in issue 171:
+<https://github.com/protesilaos/modus-themes/issues/171>.
+
 * 5.0.0 on 2025-11-01
 :PROPERTIES:
 :CUSTOM_ID: h:9232615a-02d7-4376-90a6-7e7570ac1c1e
@ -2972,7 +3454,7 @@ users, while also catering to their aesthetic preferences.
 #+begin_src text
 Modus themes version 3.0.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2022-10-28
+By Protesilaos <info@protesilaos.com> on 2022-10-28


 The version that will ship with Emacs 29
@ -3148,7 +3630,7 @@ Miscellaneous
 #+begin_src text
 Modus themes version 2.7.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2022-10-01
+By Protesilaos <info@protesilaos.com> on 2022-10-01


 Support for packages or faces
@ -3325,7 +3807,7 @@ Changes to the manual
 #+begin_src text
 Modus themes version 2.6.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2022-08-19
+By Protesilaos <info@protesilaos.com> on 2022-08-19


 Changes to supported faces or face groups
@ -3438,7 +3920,7 @@ Changes to the manual
 #+begin_src text
 Modus themes version 2.5.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2022-08-03
+By Protesilaos <info@protesilaos.com> on 2022-08-03

 This entry documents the changes made to the project since the
 publication of version 2.4.0 on 2022-06-01.  It spans more than 60
@ -3865,7 +4347,7 @@ Miscellaneous
 #+begin_src text
 Modus themes version 2.4.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2022-06-01
+By Protesilaos <info@protesilaos.com> on 2022-06-01

 This entry documents the changes made to the project since the
 publication of version 2.3.0 on 2022-04-01.  It spans more than 60
@ -4204,7 +4686,7 @@ Miscellaneous
 #+begin_src text
 Modus themes version 2.3.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2022-04-01
+By Protesilaos <info@protesilaos.com> on 2022-04-01

 This entry documents the changes made to the project since the
 publication of version 2.2.0 on 2022-02-23.  It spans more than 70
@ -4270,7 +4752,7 @@ Attempted bug fix for byte compiled files
 Quoting from the git log:

    commit f067d2ef39c22174b95584f2cba7942aaf03bcca
-    Author: Protesilaos Stavrou <info@protesilaos.com>
+    Author: Protesilaos <info@protesilaos.com>
    Date:   Thu Mar 3 06:52:31 2022 +0200

        Reify themes with eval-and-compile
@ -4504,7 +4986,7 @@ Thanks once again to everyone involved!
 #+begin_src text
 Modus themes version 2.2.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2022-02-23
+By Protesilaos <info@protesilaos.com> on 2022-02-23

 The present entry records the changes made to the project since the
 publication of version 2.1.0 on 2022-02-17.  This spans about 10 commits
@ -4614,7 +5096,7 @@ Miscellaneous changes
 #+begin_src text
 Modus themes version 2.1.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2022-02-17
+By Protesilaos <info@protesilaos.com> on 2022-02-17

 The present entry records the changes made to the project since the
 publication of version 2.0.0 on 2021-12-24.  There have been more than
@ -5323,7 +5805,7 @@ intense work which further iterated on an already solid base.
 #+begin_src text
 Modus themes version 2.0.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2021-12-24
+By Protesilaos <info@protesilaos.com> on 2021-12-24

 This entry covers the changes made to the project since the publication
 of version 1.7.0 on 2021-11-18.  There have been more than 90 commits in
@ -5705,7 +6187,7 @@ Miscellaneous
 #+begin_src text
 Modus themes version 1.7.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2021-11-18
+By Protesilaos <info@protesilaos.com> on 2021-11-18

 The present entry records the changes made to the project since the
 release of version 1.6.0 on 2021-09-29.  There have been more than 60
@ -5938,7 +6420,7 @@ Thanks once again to everyone involved!
 #+begin_src text
 Modus themes version 1.6.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2021-09-29
+By Protesilaos <info@protesilaos.com> on 2021-09-29

 This entry records the changes made to the project since the release of
 version 1.5.0 on 2021-07-15.  There have been around 70 commits since
@ -6291,7 +6773,7 @@ themes, version 1.6.0, as part of the next stable release of Emacs.
 #+begin_src text
 Modus themes version 1.5.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2021-07-15
+By Protesilaos <info@protesilaos.com> on 2021-07-15

 This entry outlines the set of changes made to the project since the
 release of version 1.4.0 on 2021-05-25.  There have been over 130
@ -6732,7 +7214,7 @@ Thanks again to everyone involved!
 #+begin_src text
 Modus themes version 1.4.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2021-05-25
+By Protesilaos <info@protesilaos.com> on 2021-05-25

 This entry records the changes made to the project since the release of
 version 1.3.0 on 2021-04-17.  There have been around 100 commits in the
@ -7051,7 +7533,7 @@ Miscellaneous
 #+begin_src text
 Modus themes version 1.3.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2021-04-17
+By Protesilaos <info@protesilaos.com> on 2021-04-17

 This entry records the changes introduced to the project since the
 publication of version 1.2.0 (2021-03-04).  There have been around 100
@ -7420,7 +7902,7 @@ Thanks once again to everyone involved!
 #+begin_src text
 Modus themes version 1.2.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2021-03-04
+By Protesilaos <info@protesilaos.com> on 2021-03-04

 This entry records the changes introduced to the project since the
 publication of version 1.1.0 (2021-01-24).  There have been close to 100
@ -7773,7 +8255,7 @@ Miscellaneous
 #+begin_src text
 Modus themes version 1.1.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2021-01-24
+By Protesilaos <info@protesilaos.com> on 2021-01-24

 This entry records the changes introduced to the project since the
 publication of version 1.0.0 (2020-12-05).  There have been around 150
@ -8234,7 +8716,7 @@ terms of face coverage, and (iv) meticulously designed throughout.
 #+begin_src text
 Modus themes version 1.0.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2020-12-05
+By Protesilaos <info@protesilaos.com> on 2020-12-05

 This entry documents the changes since version 0.13.0 (2020-10-08).
 They constitute a major release with backward-incompatible additions
@ -8641,7 +9123,7 @@ it may have introduced.
 #+begin_src text
 Modus Operandi and Modus Vivendi version 0.13.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2020-10-08
+By Protesilaos <info@protesilaos.com> on 2020-10-08

 This entry documents the changes since version 0.12.0 (2020-08-26).
 There have been around 150 commits in the meantime, making this the
@ -9172,7 +9654,7 @@ Thanks again to everyone who helped improve the themes!
 #+begin_src text
 Modus Operandi and Modus Vivendi version 0.12.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2020-08-26
+By Protesilaos <info@protesilaos.com> on 2020-08-26

 This entry documents the set of changes since version 0.11.0
 (2020-07-31).  There have been around 70 commits in the meatime, though
@ -9476,7 +9958,7 @@ their thoughts.  The people already mentioned herein:
 #+begin_src text
 Modus Operandi and Modus Vivendi version 0.11.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2020-07-31
+By Protesilaos <info@protesilaos.com> on 2020-07-31

 This entry records the changes since version 0.10.0 (2020-06-24).  The
 present release covers close to 100 commits, some of which introduce
@ -9740,7 +10222,7 @@ https://gitlab.com/protesilaos/modus-themes/-/issues
 #+begin_src text
 Modus Operandi and Modus Vivendi version 0.10.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2020-06-24
+By Protesilaos <info@protesilaos.com> on 2020-06-24

 This entry records the changes since version 0.9.0 (2020-06-03).  The
 present release is focused on stability and internal improvements.
@ -9862,7 +10344,7 @@ My thanks to Basil and André for their contributions!
 #+begin_src text
 Modus Operandi and Modus Vivendi version 0.9.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2020-06-03
+By Protesilaos <info@protesilaos.com> on 2020-06-03

 This entry records the changes since version 0.8.0 (2020-04-28).  The
 present release contains about 50 commits, covering a month of active
@ -10020,7 +10502,7 @@ Added support for
 #+begin_src text
 Modus Operandi and Modus Vivendi version 0.8.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2020-04-28
+By Protesilaos <info@protesilaos.com> on 2020-04-28

 This entry records the changes since version 0.7.0 (2020-03-30).  The
 present release contains a little more than a hundred commits, covering
@ -10194,7 +10676,7 @@ Miscellaneous changes and concluding remarks
 #+begin_src text
 Modus Operandi and Modus Vivendi version 0.7.0

-By Protesilaos Stavrou <info@protesilaos.com> on 2020-03-30
+By Protesilaos <info@protesilaos.com> on 2020-03-30

 This entry documents the changes since version 0.6.0 (2020-03-01).  The
 present release is the largest to date containing 110 commits.
--- a/README.md
+++ b/README.md
@ -67,7 +67,8 @@ The manual has a section about building on top of Modus. My
   ("C-<f5>" . modus-themes-select)
   ("M-<f5>" . modus-themes-load-random))
  :config
-  ;; Your customizations here:
+  ;; Your customizations here.  All customizations must evaluated
+  ;; BEFORE loading the theme.
  (setq modus-themes-to-toggle '(modus-operandi modus-vivendi)
        modus-themes-to-rotate modus-themes-items
        modus-themes-mixed-fonts t
@ -88,3 +89,49 @@ The manual has a section about building on top of Modus. My
  ;; `modus-themes-load-random-light').
  (modus-themes-load-theme 'modus-operandi))
 ```
+
+## Links to other projects
+
+In this section I collect links to other themes built on top of Modus,
+have Modus as a dependency, or are porting Modus to some other
+platform. You are welcome to append your project to the relevant list.
+
+In linking to these projects, I am not endorsing anybody's views.
+
+### Emacs themes based on Modus
+
+This is not an exhaustive list. You are welcome to add your package
+here. Newer projects are at the bottom and are added as I am made
+aware of them.
+
+- `ef-themes` by Protesilaos <https://github.com/protesilaos/ef-themes>
+- `standard-themes` by Protesilaos <https://github.com/protesilaos/standard-themes>
+- `modus-ewal-theme` by Oliwier Czerwiński <https://github.com/deadendpl/modus-ewal-theme>
+- `modus-flexoki` by Derek Passen <https://github.com/dpassen/modus-flexoki>
+- `faff-theme` (since version 4) by James Ferguson <https://github.com/WJCFerguson/emacs-faff-theme>
+- `modus-catpuccin` by Magnus Therning <https://gitlab.com/magus/modus-catppuccin>
+- `pixel-themes` by Lucas <https://github.com/lucasobx/pixel-themes>
+- `modus-nordic` (`modus-nordic-night` and `modus-nordic-midnight`) by Ashton Wiersdorf <https://codeberg.org/ashton314/modus-nordic-night>
+- `folio-theme` by kn66 (nobu43) <https://github.com/kn66/folio-theme.el>
+- `modus-alabaster` by Derek Passen <https://github.com/dpassen/modus-alabaster>
+- `modus-vague` by Ashish Panigrahi <https://github.com/paniash/modus-vague.git>
+- `peppers-theme` by Joar von Arndt <https://codeberg.org/joar/peppers-theme>
+
+### Other Emacs packages based on Modus
+
+- `modus-themes-exporter` by Protesilaos <https://github.com/protesilaos/modus-themes-exporter>
+
+### Projects inspired by the Modus themes
+
+This is not an exhaustive list. You are welcome to add your project here.
+
+- `hugo-modus` by Yejun Su is a theme for the Hugo static site
+  generator: <https://github.com/goofansu/hugo-modus>. It uses colours
+  from the Modus themes.
+- `modus-themes.nvim` by Miika Nissi and others is a port for NeoVim:
+  <https://github.com/miikanissi/modus-themes.nvim>.
+- `zed-modus-themes` by Vitaly Slobodin is a port for the Zed editor:
+  <https://github.com/vitallium/zed-modus-themes>.
+- `word-smith` by Sadsnake1 is a distraction-free writing for Obsidian
+  that includes ports of the Modus themes: <https://github.com/Sadsnake1/word-smith>
+- `omarchy-modus-themes` by Dhavan Vaidya: <https://github.com/codingquark/omarchy-modus-themes>
--- a/doc/modus-themes.info
+++ b/doc/modus-themes.info
--- a/doc/modus-themes.org
+++ b/doc/modus-themes.org
--- a/modus-operandi-deuteranopia-theme.el
+++ b/modus-operandi-deuteranopia-theme.el
@ -1,9 +1,9 @@
 ;;; modus-operandi-deuteranopia-theme.el --- Deuteranopia-optimized theme with a white background -*- lexical-binding:t -*-

-;; Copyright (C) 2019-2025  Free Software Foundation, Inc.
+;; Copyright (C) 2019-2026  Free Software Foundation, Inc.

-;; Author: Protesilaos Stavrou <info@protesilaos.com>
-;; Maintainer: Protesilaos Stavrou <info@protesilaos.com>
+;; Author: Protesilaos <info@protesilaos.com>
+;; Maintainer: Protesilaos <info@protesilaos.com>
 ;; URL: https://github.com/protesilaos/modus-themes
 ;; Keywords: faces, theme, accessibility

@ -87,6 +87,9 @@ standard)."
 'light
 'modus-themes-operandi-deuteranopia-palette
 'modus-operandi-deuteranopia-palette-user
- 'modus-operandi-deuteranopia-palette-overrides)
+ 'modus-operandi-deuteranopia-palette-overrides
+ 'modus-themes-faces-deuteranopia)
+
+(provide 'modus-operandi-deuteranopia-theme)

 ;;; modus-operandi-deuteranopia-theme.el ends here
--- a/modus-operandi-theme.el
+++ b/modus-operandi-theme.el
@ -1,9 +1,9 @@
 ;;; modus-operandi-theme.el --- Elegant, highly legible theme with a white background -*- lexical-binding:t -*-

-;; Copyright (C) 2019-2025  Free Software Foundation, Inc.
+;; Copyright (C) 2019-2026  Free Software Foundation, Inc.

-;; Author: Protesilaos Stavrou <info@protesilaos.com>
-;; Maintainer: Protesilaos Stavrou <info@protesilaos.com>
+;; Author: Protesilaos <info@protesilaos.com>
+;; Maintainer: Protesilaos <info@protesilaos.com>
 ;; URL: https://github.com/protesilaos/modus-themes
 ;; Keywords: faces, theme, accessibility

@ -87,4 +87,6 @@ which corresponds to a minimum contrast in relative luminance of
 'modus-operandi-palette-user
 'modus-operandi-palette-overrides)

+(provide 'modus-operandi-theme)
+
 ;;; modus-operandi-theme.el ends here
--- a/modus-operandi-tinted-theme.el
+++ b/modus-operandi-tinted-theme.el
@ -1,9 +1,9 @@
 ;;; modus-operandi-tinted-theme.el --- Elegant, highly legible theme with a light ochre background -*- lexical-binding:t -*-

-;; Copyright (C) 2019-2025  Free Software Foundation, Inc.
+;; Copyright (C) 2019-2026  Free Software Foundation, Inc.

-;; Author: Protesilaos Stavrou <info@protesilaos.com>
-;; Maintainer: Protesilaos Stavrou <info@protesilaos.com>
+;; Author: Protesilaos <info@protesilaos.com>
+;; Maintainer: Protesilaos <info@protesilaos.com>
 ;; URL: https://github.com/protesilaos/modus-themes
 ;; Keywords: faces, theme, accessibility

@ -87,4 +87,6 @@ which corresponds to a minimum contrast in relative luminance of
 'modus-operandi-tinted-palette-user
 'modus-operandi-tinted-palette-overrides)

+(provide 'modus-operandi-tinted-theme)
+
 ;;; modus-operandi-tinted-theme.el ends here
--- a/modus-operandi-tritanopia-theme.el
+++ b/modus-operandi-tritanopia-theme.el
@ -1,9 +1,9 @@
 ;;; modus-operandi-tritanopia-theme.el --- Tritanopia-optimized theme with a white background -*- lexical-binding:t -*-

-;; Copyright (C) 2019-2025  Free Software Foundation, Inc.
+;; Copyright (C) 2019-2026  Free Software Foundation, Inc.

-;; Author: Protesilaos Stavrou <info@protesilaos.com>
-;; Maintainer: Protesilaos Stavrou <info@protesilaos.com>
+;; Author: Protesilaos <info@protesilaos.com>
+;; Maintainer: Protesilaos <info@protesilaos.com>
 ;; URL: https://github.com/protesilaos/modus-themes
 ;; Keywords: faces, theme, accessibility

@ -87,6 +87,9 @@ standard)."
 'light
 'modus-themes-operandi-tritanopia-palette
 'modus-operandi-tritanopia-palette-user
- 'modus-operandi-tritanopia-palette-overrides)
+ 'modus-operandi-tritanopia-palette-overrides
+ 'modus-themes-faces-tritanopia)
+
+(provide 'modus-operandi-tritanopia-theme)

 ;;; modus-operandi-tritanopia-theme.el ends here
--- a/modus-themes.el
+++ b/modus-themes.el
--- a/modus-vivendi-deuteranopia-theme.el
+++ b/modus-vivendi-deuteranopia-theme.el
@ -1,9 +1,9 @@
 ;;; modus-vivendi-deuteranopia-theme.el --- Deuteranopia-optimized theme with a black background -*- lexical-binding:t -*-

-;; Copyright (C) 2019-2025  Free Software Foundation, Inc.
+;; Copyright (C) 2019-2026  Free Software Foundation, Inc.

-;; Author: Protesilaos Stavrou <info@protesilaos.com>
-;; Maintainer: Protesilaos Stavrou <info@protesilaos.com>
+;; Author: Protesilaos <info@protesilaos.com>
+;; Maintainer: Protesilaos <info@protesilaos.com>
 ;; URL: https://github.com/protesilaos/modus-themes
 ;; Keywords: faces, theme, accessibility

@ -87,6 +87,9 @@ standard)."
 'dark
 'modus-themes-vivendi-deuteranopia-palette
 'modus-vivendi-deuteranopia-palette-user
- 'modus-vivendi-deuteranopia-palette-overrides)
+ 'modus-vivendi-deuteranopia-palette-overrides
+ 'modus-themes-faces-deuteranopia)
+
+(provide 'modus-vivendi-deuteranopia-theme)

 ;;; modus-vivendi-deuteranopia-theme.el ends here
--- a/modus-vivendi-theme.el
+++ b/modus-vivendi-theme.el
@ -1,9 +1,9 @@
 ;;; modus-vivendi-theme.el --- Elegant, highly legible theme with a black background -*- lexical-binding:t -*-

-;; Copyright (C) 2019-2025  Free Software Foundation, Inc.
+;; Copyright (C) 2019-2026  Free Software Foundation, Inc.

-;; Author: Protesilaos Stavrou <info@protesilaos.com>
-;; Maintainer: Protesilaos Stavrou <info@protesilaos.com>
+;; Author: Protesilaos <info@protesilaos.com>
+;; Maintainer: Protesilaos <info@protesilaos.com>
 ;; URL: https://github.com/protesilaos/modus-themes
 ;; Keywords: faces, theme, accessibility

@ -87,4 +87,6 @@ which corresponds to a minimum contrast in relative luminance of
 'modus-vivendi-palette-user
 'modus-vivendi-palette-overrides)

+(provide 'modus-vivendi-theme)
+
 ;;; modus-vivendi-theme.el ends here
--- a/modus-vivendi-tinted-theme.el
+++ b/modus-vivendi-tinted-theme.el
@ -1,9 +1,9 @@
 ;;; modus-vivendi-tinted-theme.el --- Elegant, highly legible theme with a night sky background -*- lexical-binding:t -*-

-;; Copyright (C) 2019-2025  Free Software Foundation, Inc.
+;; Copyright (C) 2019-2026  Free Software Foundation, Inc.

-;; Author: Protesilaos Stavrou <info@protesilaos.com>
-;; Maintainer: Protesilaos Stavrou <info@protesilaos.com>
+;; Author: Protesilaos <info@protesilaos.com>
+;; Maintainer: Protesilaos <info@protesilaos.com>
 ;; URL: https://github.com/protesilaos/modus-themes
 ;; Keywords: faces, theme, accessibility

@ -87,4 +87,6 @@ which corresponds to a minimum contrast in relative luminance of
 'modus-vivendi-tinted-palette-user
 'modus-vivendi-tinted-palette-overrides)

+(provide 'modus-vivendi-tinted-theme)
+
 ;;; modus-vivendi-tinted-theme.el ends here
--- a/modus-vivendi-tritanopia-theme.el
+++ b/modus-vivendi-tritanopia-theme.el
@ -1,9 +1,9 @@
 ;;; modus-vivendi-tritanopia-theme.el --- Tritanopia-optimized theme with a black background -*- lexical-binding:t -*-

-;; Copyright (C) 2019-2025  Free Software Foundation, Inc.
+;; Copyright (C) 2019-2026  Free Software Foundation, Inc.

-;; Author: Protesilaos Stavrou <info@protesilaos.com>
-;; Maintainer: Protesilaos Stavrou <info@protesilaos.com>
+;; Author: Protesilaos <info@protesilaos.com>
+;; Maintainer: Protesilaos <info@protesilaos.com>
 ;; URL: https://github.com/protesilaos/modus-themes
 ;; Keywords: faces, theme, accessibility

@ -87,6 +87,9 @@ standard)."
 'dark
 'modus-themes-vivendi-tritanopia-palette
 'modus-vivendi-tritanopia-palette-user
- 'modus-vivendi-tritanopia-palette-overrides)
+ 'modus-vivendi-tritanopia-palette-overrides
+ 'modus-themes-faces-tritanopia)
+
+(provide 'modus-vivendi-tritanopia-theme)

 ;;; modus-vivendi-tritanopia-theme.el ends here
--- a/tests/modus-themes-test.el
+++ b/tests/modus-themes-test.el
@ -0,0 +1,372 @@
+;;; modus-themes-test.el --- Unit tests for the Modus themes -*- lexical-binding: t -*-
+
+;; Copyright (C) 2025-2026  Free Software Foundation, Inc.
+
+;; Author: Protesilaos <info@protesilaos.com>,
+;;         Rudolf Adamkovič <rudolf@adamkovic.org>
+;; Maintainer: Protesilaos <info@protesilaos.com>
+;; URL: https://github.com/protesilaos/modus-themes
+
+;; This file is NOT part of GNU Emacs.
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+;;
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Tests for the Modus themes.  Note that we are using Shorthands in
+;; this file, so the "mtt-" prefix really is "modus-themes-test-".
+;; Evaluate the following to learn more:
+;;
+;;    (info "(elisp) Shorthands")
+
+;;; Code:
+
+(require 'ert)
+(require 'modus-themes)
+
+(defmacro mtt-define-test (symbol &rest body)
+  "Write test for SYMBOL with BODY forms.
+If the `car' of BODY is a string, use it as the docstring of the test.
+Else provide a generic snippet of text."
+  (declare (doc-string 2) (indent defun))
+  (let* ((first (car body))
+         (has-docstring (stringp first))
+         (docstring (if has-docstring
+                        first
+                      (format "Test that `%s' does the right thing." symbol)))
+         (body (if has-docstring (cdr body) body)))
+    `(ert-deftest ,(intern (format "mtt-%s" symbol)) ()
+       ,docstring
+       ,@body)))
+
+(mtt-define-test modus-themes--color-hex-p
+  (should (modus-themes--color-hex-p "#123"))
+  (should (modus-themes--color-hex-p "#123456"))
+  (should (modus-themes--color-hex-p "#abc"))
+  (should (modus-themes--color-hex-p "#ABCDEF"))
+  (should-not (modus-themes--color-hex-p "abc"))
+  (should-not (modus-themes--color-hex-p "#abcd"))
+  (should-not (modus-themes--color-hex-p "#12345"))
+  (should-not (modus-themes--color-hex-p "#1234567"))
+  (should-not (modus-themes--color-hex-p "#zzz"))
+  (should-not (modus-themes--color-hex-p "#zzz"))
+  (should-not (modus-themes--color-hex-p "#12g456")))
+
+(mtt-define-test modus-themes--hex-or-name-to-rgb
+  (should (equal (modus-themes--hex-or-name-to-rgb "#fff") (list 1.0 1.0 1.0)))
+  (should (equal (modus-themes--hex-or-name-to-rgb "#000") (list 0.0 0.0 0.0)))
+  (should (equal (modus-themes--hex-or-name-to-rgb "#f00") (list 1.0 0.0 0.0)))
+  (should (equal (modus-themes--hex-or-name-to-rgb "#0f0") (list 0.0 1.0 0.0)))
+  (should (equal (modus-themes--hex-or-name-to-rgb "#00f") (list 0.0 0.0 1.0)))
+  (should (equal (modus-themes--hex-or-name-to-rgb "#ffffff") (list 1.0 1.0 1.0)))
+  (should (equal (modus-themes--hex-or-name-to-rgb "#000000") (list 0.0 0.0 0.0)))
+  (should (equal (modus-themes--hex-or-name-to-rgb "#ff0000") (list 1.0 0.0 0.0)))
+  (should (equal (modus-themes--hex-or-name-to-rgb "#00ff00") (list 0.0 1.0 0.0)))
+  ;; NOTE 2026-04-12: I do not need it to be precise here, hence the `format'.
+  (let ((rgb-rounded-fn
+         (lambda (hex)
+           (let ((rgb (modus-themes--hex-or-name-to-rgb hex)))
+             (mapcar (lambda (float) (string-to-number (format "%.2f" float))) rgb)))))
+    (should (equal (funcall rgb-rounded-fn "#800000") (list 0.5 0.0 0.0)))
+    (should (equal (funcall rgb-rounded-fn "#008000") (list 0.0 0.5 0.0)))
+    (should (equal (funcall rgb-rounded-fn "#000080") (list 0.0 0.0 0.5))))
+  (should-error (modus-themes--hex-or-name-to-rgb ""))
+  (should-error (modus-themes--hex-or-name-to-rgb "#"))
+  (should-error (modus-themes--hex-or-name-to-rgb "#1"))
+  (should-error (modus-themes--hex-or-name-to-rgb "#12"))
+  (should-error (modus-themes--hex-or-name-to-rgb "#1234"))
+  (should-error (modus-themes--hex-or-name-to-rgb "#12345"))
+  (should-error (modus-themes--hex-or-name-to-rgb "#gggggg"))
+  (should-error (modus-themes--hex-or-name-to-rgb (list 1.0 1.0 1.0))))
+
+(mtt-define-test modus-themes-wcag-formula
+  "Test that `modus-themes-wcag-formula' does the right thing.
+Also see `modus-themes-test--modus-themes--hex-to-rgb'."
+  (should (= (modus-themes-wcag-formula "#ffffff") 1.0))
+  (should (= (modus-themes-wcag-formula "#000000") 0.0))
+  (should-error (modus-themes-wcag-formula "#00000")))
+
+(mtt-define-test modus-themes-contrast
+  "Test that `modus-themes-contrast' works as intended.
+Also see `modus-themes-test--modus-themes--hex-to-rgb'."
+  (should (= (modus-themes-contrast "#ffffff" "#000000") 21.0))
+  (should (= (modus-themes-contrast "#000000" "#ffffff") 21.0))
+  ;; NOTE 2026-04-12: I do not need it to be precise here, hence the `format'.
+  (let ((float-2-fn (lambda (hex1 hex2) (string-to-number (format "%.2f" (modus-themes-contrast hex1 hex2))))))
+    (should (= (funcall float-2-fn "#ff0000" "#ffffff")  4.0))
+    (should (= (funcall float-2-fn "#00ff00" "#ffffff") 1.37))
+    (should (= (funcall float-2-fn "#0000ff" "#ffffff") 8.59))
+    (should (= (funcall float-2-fn "#ffff00" "#ffffff") 1.07))
+    (should (= (funcall float-2-fn "#00ffff" "#ffffff") 1.25))
+    (should (= (funcall float-2-fn "#ff00ff" "#ffffff") 3.14)))
+  (should-error (modus-themes-contrast "#ffffff" "#00000"))
+  (should-error (modus-themes-contrast "#fffff" "#00000")))
+
+(mtt-define-test modus-themes--color-eight-to-six-digits
+  (should (string= (modus-themes--color-eight-to-six-digits "#f00") "#f00"))
+  (should (string= (modus-themes--color-eight-to-six-digits "#ff1919") "#ff1919"))
+  (should (string= (modus-themes--color-eight-to-six-digits "#ffff19991999") "#ff1919")))
+
+(mtt-define-test modus-themes-adjust-value
+  "Test that `modus-themes-adjust-value' does the right thing.
+Also see `modus-themes-test--modus-themes--hex-to-rgb'."
+  (should (string= (modus-themes-adjust-value "#ff0000" 10) "#ff1919"))
+  (should (string= (modus-themes-adjust-value "#505050" 100) "#ffffff"))
+  (should (string= (modus-themes-adjust-value "#505050" -100) "#000000"))
+  (should (string= (modus-themes-adjust-value "#505050" 0) "#505050"))
+  (should-error (modus-themes-adjust-value "#ff00" 10)))
+
+(mtt-define-test modus-themes-activate
+  (if (custom-theme-p 'modus-operandi-tritanopia)
+      (should-not (modus-themes-activate 'modus-operandi-tritanopia))
+    (should (custom-theme-p 'modus-operandi-tritanopia))))
+
+(mtt-define-test modus-themes--belongs-to-family-p
+  (should (modus-themes--belongs-to-family-p 'modus-operandi 'modus-themes))
+  (should-not (modus-themes--belongs-to-family-p 'my-fancy-theme 'modus-themes))
+  (should-not (modus-themes--belongs-to-family-p 'modus-operandi 'my-fancy-themes)))
+
+(mtt-define-test modus-themes-get-all-known-themes
+  (should (equal (modus-themes-get-all-known-themes) modus-themes-items))
+  (should-not (modus-themes-get-all-known-themes 'my-fancy-themes)))
+
+(mtt-define-test modus-themes--background-p
+  (should (modus-themes--background-p 'modus-operandi 'light))
+  (should-not (modus-themes--background-p 'modus-operandi 'dark))
+  (should-not (modus-themes--background-p 'modus-operandi t))
+  (should-not (modus-themes--background-p 'modus-operandi :light)))
+
+(mtt-define-test modus-themes-sort
+  (let ((first-has-prefix-fn (lambda (themes prefix)
+                               (when-let* ((first (car themes))
+                                           (name (symbol-name first)))
+                                 (string-match-p prefix name)))))
+    (should (funcall first-has-prefix-fn (modus-themes-sort (reverse modus-themes-items) 'light) "modus-operandi"))
+    (should (funcall first-has-prefix-fn (modus-themes-sort modus-themes-items 'dark) "modus-vivendi"))))
+
+(mtt-define-test inheritance
+  "Ensure all faces inherit from valid faces."
+  ;; Third-party packages, loaded if possible to better test face inheritance.
+  (require 'font-latex nil t)
+  (let ((current-theme (modus-themes-get-current-theme)))
+    (unwind-protect
+        (progn
+          (modus-themes-load-theme 'modus-operandi)
+          (should-not (seq-filter
+                       (lambda (face)
+                         ;; The face either has no parent ...
+                         (if-let* ((parent (face-attribute face :inherit)))
+                             (and (symbolp parent)
+                                  (not (eq parent 'unspecified))
+                                  ;; ... or its parent is a valid face.
+                                  (not (facep parent)))))
+                       (face-list))))
+      (modus-themes-load-theme current-theme))))
+
+(mtt-define-test color-dark-p
+  (let ((modus-operandi-sample-foregrounds
+         '("#a60000"
+           "#972500"
+           "#a0132f"
+           "#7f0000"
+           "#006800"
+           "#316500"
+           "#00663f"
+           "#2a5045"
+           "#6f5500"
+           "#884900"
+           "#7a4f2f"
+           "#624416"
+           "#0031a9"
+           "#3548cf"
+           "#0000b0"
+           "#003497"
+           "#721045"
+           "#8f0075"
+           "#531ab6"
+           "#7c318f"
+           "#005e8b"
+           "#3f578f"
+           "#005f5f"
+           "#005077"))
+        (modus-vivendi-sample-foregrounds
+         '("#ff5f59"
+           "#ff6b55"
+           "#ff7f86"
+           "#ff9580"
+           "#44bc44"
+           "#70b900"
+           "#00c06f"
+           "#88ca9f"
+           "#d0bc00"
+           "#fec43f"
+           "#dfaf7a"
+           "#d2b580"
+           "#2fafff"
+           "#79a8ff"
+           "#00bcff"
+           "#82b0ec"
+           "#feacd0"
+           "#f78fe7"
+           "#b6a0ff"
+           "#caa6df"
+           "#00d3d0"
+           "#4ae2f0"
+           "#6ae4b9"
+           "#9ac8e0")))
+    (should (seq-every-p #'modus-themes-color-dark-p modus-operandi-sample-foregrounds))
+    (should-not (seq-every-p #'modus-themes-color-dark-p modus-vivendi-sample-foregrounds))))
+
+(mtt-define-test get-readable-foreground
+  (let ((modus-operandi-sample-foregrounds
+         '("#a60000"
+           "#972500"
+           "#a0132f"
+           "#7f0000"
+           "#006800"
+           "#316500"
+           "#00663f"
+           "#2a5045"
+           "#6f5500"
+           "#884900"
+           "#7a4f2f"
+           "#624416"
+           "#0031a9"
+           "#3548cf"
+           "#0000b0"
+           "#003497"
+           "#721045"
+           "#8f0075"
+           "#531ab6"
+           "#7c318f"
+           "#005e8b"
+           "#3f578f"
+           "#005f5f"
+           "#005077"))
+        (modus-vivendi-sample-foregrounds
+         '("#ff5f59"
+           "#ff6b55"
+           "#ff7f86"
+           "#ff9580"
+           "#44bc44"
+           "#70b900"
+           "#00c06f"
+           "#88ca9f"
+           "#d0bc00"
+           "#fec43f"
+           "#dfaf7a"
+           "#d2b580"
+           "#2fafff"
+           "#79a8ff"
+           "#00bcff"
+           "#82b0ec"
+           "#feacd0"
+           "#f78fe7"
+           "#b6a0ff"
+           "#caa6df"
+           "#00d3d0"
+           "#4ae2f0"
+           "#6ae4b9"
+           "#9ac8e0")))
+    (should (seq-every-p
+             (lambda (value)
+               (string= value "#ffffff"))
+             (mapcar #'modus-themes-get-readable-foreground modus-operandi-sample-foregrounds)))
+    (should (seq-every-p
+             (lambda (value)
+               (string= value "#000000"))
+             (mapcar #'modus-themes-get-readable-foreground modus-vivendi-sample-foregrounds)))))
+
+(mtt-define-test complete-palette-mappings
+  "Ensure all built-in palettes contain entries for all palette mappings.
+This computes a complete list of mapping names from the built-in palettes
+and then cross-checks the palettes against the list. This should help ensure
+consistency and completeness where adding a new mapping in one palette will
+fail this test until it is added in all palettes."
+  (let* ((operandi-names (seq-uniq (mapcar #'car modus-themes-operandi-palette)))
+         (operandi-tinted-names (seq-uniq (mapcar #'car modus-themes-operandi-tinted-palette)))
+         (operandi-deuteranopia-names (seq-uniq (mapcar #'car modus-themes-operandi-deuteranopia-palette)))
+         (operandi-tritanopia-names (seq-uniq (mapcar #'car modus-themes-operandi-tritanopia-palette)))
+         (vivendi-names (seq-uniq (mapcar #'car modus-themes-vivendi-palette)))
+         (vivendi-tinted-names (seq-uniq (mapcar #'car modus-themes-vivendi-tinted-palette)))
+         (vivendi-deuteranopia-names (seq-uniq (mapcar #'car modus-themes-vivendi-deuteranopia-palette)))
+         (vivendi-tritanopia-names (seq-uniq (mapcar #'car modus-themes-vivendi-tritanopia-palette)))
+         (all-names (seq-uniq (append operandi-names
+                                      operandi-tinted-names
+                                      operandi-deuteranopia-names
+                                      operandi-tritanopia-names
+                                      vivendi-names
+                                      vivendi-tinted-names
+                                      vivendi-deuteranopia-names
+                                      vivendi-tritanopia-names))))
+    (should (seq-empty-p (seq-difference all-names operandi-names)))
+    (should (seq-empty-p (seq-difference all-names operandi-tinted-names)))
+    (should (seq-empty-p (seq-difference all-names operandi-deuteranopia-names)))
+    (should (seq-empty-p (seq-difference all-names operandi-tritanopia-names)))
+    (should (seq-empty-p (seq-difference all-names vivendi-names)))
+    (should (seq-empty-p (seq-difference all-names vivendi-tinted-names)))
+    (should (seq-empty-p (seq-difference all-names vivendi-deuteranopia-names)))
+    (should (seq-empty-p (seq-difference all-names vivendi-tritanopia-names)))))
+
+(mtt-define-test modus-themes-generate-palette
+  "Ensure `modus-themes-generate-palette' provides enough mapping coverage
+such that the generated palette does not inherit explicit color values
+from a parent core palette."
+  (let* ((generated-palette (modus-themes-generate-palette
+                             '((fg-main "#ffffff")
+                               (bg-main "#000000")
+                               (red "#ff0000")
+                               (green "#00ff00")
+                               (yellow "#ffff00")
+                               (blue "#0000ff")
+                               (magenta "#ff00ff")
+                               (cyan "#00ffff"))))
+         ;; These are colors we expect to have an explicit hex value,
+         ;; either because they were provided explicitly in the call to
+         ;; `modus-themes-generate-palette' above, or because we expect
+         ;; `modus-themes-generate-palette' to generate the color.
+         (explicit-colors '( fg-main bg-main
+                             fg-alt fg-dim bg-inactive bg-active bg-dim border
+                             ;; cyan
+                             cyan bg-cyan-nuanced bg-cyan-subtle bg-cyan-intense
+                             cyan-intense cyan-faint cyan-cooler cyan-warmer
+                             ;; magenta
+                             magenta bg-magenta-nuanced bg-magenta-subtle bg-magenta-intense
+                             magenta-intense magenta-faint magenta-cooler magenta-warmer
+                             ;; blue
+                             blue bg-blue-nuanced bg-blue-subtle bg-blue-intense
+                             blue-intense blue-faint blue-cooler blue-warmer
+                             ;; yellow
+                             yellow bg-yellow-nuanced bg-yellow-subtle bg-yellow-intense
+                             yellow-intense yellow-faint yellow-cooler yellow-warmer
+                             ;; green
+                             green bg-green-nuanced bg-green-subtle bg-green-intense
+                             green-intense green-faint green-cooler green-warmer
+                             ;; red
+                             red bg-red-nuanced bg-red-subtle bg-red-intense
+                             red-intense red-faint red-cooler red-warmer)))
+    ;; Ensure all other colors in the palette map to a color name and not an
+    ;; explicit hex value. If this check fails, the offending color should
+    ;; be mapped to an appropriate color name in `modus-themes-generate-palette'.
+    (should (seq-empty-p (seq-remove (lambda (elem)
+                                       (or (member (car elem) explicit-colors)
+                                           (symbolp (cadr elem))))
+                                     generated-palette)))))
+
+(provide 'modus-themes-test)
+;;; modus-themes-test.el ends here
+
+;; Local Variables:
+;; read-symbol-shorthands: (("mtt" . "modus-themes-test-"))
+;; End: