diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..a0ef753
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1 @@
+*.add merge=union
diff --git a/.vimrc b/.vimrc
index 78ae230..5bce502 100644
--- a/.vimrc
+++ b/.vimrc
@@ -130,6 +130,13 @@ endif
 " Remove object files from file globs
 set wildignore+=*.o
 
+" Regenerate binary spell files if the .add files were modified
+for d in glob('~/.vim/spell/*.add', 1, 1)
+    if filereadable(d) && (!filereadable(d . '.spl') || getftime(d) > getftime(d . '.spl'))
+        exec 'mkspell! ' . fnameescape(d)
+    endif
+endfor
+
 " Show a tree-style netrw listing
 let g:netrw_home = '~/.netrw'
 let g:netrw_liststyle = 3
diff --git a/vimfiles/spell/.gitignore b/vimfiles/spell/.gitignore
new file mode 100644
index 0000000..6d535c0
--- /dev/null
+++ b/vimfiles/spell/.gitignore
@@ -0,0 +1 @@
+*.spl