diff --git a/profiles/vim.nix b/profiles/vim.nix
index 9c8be10..a5103ce 100644
--- a/profiles/vim.nix
+++ b/profiles/vim.nix
@@ -76,6 +76,37 @@ vim_configurable.customize {
         autocmd BufWritePost,FileWritePost    *.gpg   u
     augroup END
 
+    " Manage ISO files
+    augroup iso
+        au!
+
+        " First make sure nothing is written to ~/.viminfo while editing an encrypted file.
+        autocmd BufReadPre,FileReadPre      *.iso set viminfo=
+        " We don't want a swap file, as it writes unencrypted data to disk
+        autocmd BufReadPre,FileReadPre      *.iso set noswapfile
+        " Switch to binary mode to read the encrypted file
+        autocmd BufReadPre,FileReadPre      *.iso set bin
+        autocmd BufReadPre,FileReadPre      *.iso let ch_save = &ch|set ch=2
+        autocmd BufReadPost,FileReadPost    *.iso '[,']!gpg --decrypt 2> /dev/null
+        " Switch to normal mode for editing
+        autocmd BufReadPost,FileReadPost    *.iso set nobin
+        autocmd BufReadPost,FileReadPost    *.iso let &ch = ch_save|unlet ch_save
+        autocmd BufReadPost,FileReadPost    *.iso execute ":doautocmd BufReadPost " . expand("%:r")
+
+        " Convert all text to encrypted text before writing
+        autocmd BufWritePre,FileWritePre    *.iso   '[,']!gpg --default-key=A4122FF3971B6865 --default-recipient-self -ae 2>/dev/null
+        " Undo the encryption so we are back in the normal text, directly
+        " after the file has been written.
+        autocmd BufWritePost,FileWritePost    *.iso   u
+    augroup END
+
+    " Use persistent history.
+    if !isdirectory("/tmp/.vim-undo-dir")
+        call mkdir("/tmp/.vim-undo-dir", "", 0700)
+    endif
+    set undodir=/tmp/.vim-undo-dir
+    set undofile
+
     " My Markdown environment
     function! MarkdownSettings()
         set textwidth=79