New option: g:startify_disable_at_vimenter

doc/startify.txt

@@ -95,6 +95,7 @@ default values.
     |g:startify_enable_special|
     |g:startify_session_savevars|
     |g:startify_session_savecmds|
+    |g:startify_disable_at_vimenter|
 
 
 ============-                                           *g:startify_session_dir*
@@ -346,6 +347,14 @@ A hardcoded example:
 Same as the custom header, but shown at the bottom of the startify buffer.
 
 
+============-                                   *g:startify_disable_at_vimenter*
+
+    let g:startify_disable_at_vimenter = 0
+
+Don't run Startify at Vim startup. You can still call it anytime via
+:Startify.
+
+
 ==============================================================================
 4. Commands                                                  *startify-commands*
 

plugin/startify.vim

@@ -11,11 +11,13 @@ endif
 let g:loaded_startify = 1
 
 augroup startify
-  autocmd VimEnter *
-        \ if !argc() && (line2byte('$') == -1) && (v:progname =~? '^[gm]\=vimx\=\%[\.exe]$') |
-        \   call startify#insane_in_the_membrane() |
-        \ endif |
-        \ autocmd! startify VimEnter
+  if !get(g:, 'startify_disable_at_vimenter')
+    autocmd VimEnter *
+          \ if !argc() && (line2byte('$') == -1) && (v:progname =~? '^[gm]\=vimx\=\%[\.exe]$') |
+          \   call startify#insane_in_the_membrane() |
+          \ endif |
+          \ autocmd! startify VimEnter
+  endif
 augroup END
 
 command! -nargs=? -bar -complete=customlist,startify#session_list SSave   call startify#session_save(<f-args>)