diff --git a/roles/vim.nix b/roles/vim.nix
index 6715ca9..3d1e4c2 100644
--- a/roles/vim.nix
+++ b/roles/vim.nix
@@ -74,9 +74,6 @@ vim_configurable.customize {
         autocmd BufWritePost,FileWritePost    *.gpg   u
     augroup END
 
-    " Add files ending in md to the list of files recognised as markdown:
-    autocmd BufNewFile,BufFilePre,BufRead *.md set filetype=markdown
-
     " My Markdown environment
     function! MarkdownSettings()
         set textwidth=79
@@ -119,6 +116,16 @@ vim_configurable.customize {
     endfunction
     autocmd BufNewFile,BufFilePre,BufRead *.nix :call NixSettings()
 
+    " Settings for my Crystal environment:
+    function! CrystalSettings()
+        set tabstop=2
+        set shiftwidth=2
+        set expandtab
+        set textwidth=79
+        set filetype=crystal
+    endfunction
+    autocmd BufNewFile,BufFilePre,BufRead *.cr :call CrystalSettings()
+
     " Settings for my Golang environment:
     function! GoSettings()
         set tabstop=7