refactor: reorganize indentation config

config.org

@@ -4120,6 +4120,14 @@ Operators being in italics looks ugly, so let's fix that.
 :lang (web +lsp +tree-sitter)
 #+end_src
 
+*** Indentation
+
+#+begin_src emacs-lisp
+(after! css-mode
+  (setq css-indent-offset 2))
+#+end_src
+
+
 ** Idris
 :PROPERTIES:
 :header-args:emacs-lisp: :noweb-ref idris-config
@@ -4204,17 +4212,6 @@ Operators being in italics looks ugly in this mode too, but due to Idris's more
   `(idris-semantic-postulate-face :foreground ,(doom-color 'yellow)))
 #+end_src
 
-** Indentation
-
-#+call: confpkg("Indent")
-
-I prefer 2-space indentation in all circumstances. Unfortunately, Emacs's indentation is mode-specific, so I have to configure every mode's indentation separately.
-
-#+begin_src emacs-lisp
-(after! css-mode
-  (setq css-indent-offset 2))
-#+end_src
-
 ** Java
 
 #+call: confpkg("Mode: Java")
@@ -4377,6 +4374,16 @@ The Agda integration with Markdown specifically requires some changes to the pol
 
 #+begin_src emacs-lisp :noweb-ref doom-module
 :lang (nix +lsp +tree-sitter)
+:tools direnv
+#+end_src
+
+*** Indentation
+
+EditorConfig can't find this mode's indentation variables itself, so we'll have to tell it where they are.
+
+#+begin_src emacs-lisp
+(after! editorconfig
+  (push '(nix-ts-mode nix-ts-mode-indent-offset) editorconfig-indentation-alist))
 #+end_src
 
 ** Python