diff --git a/README.md b/README.md
index 8513c64..4df3561 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,7 @@ Lean & mean statusline for vim that's light as air.
 *  looks good with regular fonts and provides configuration points so you can use unicode or powerline symbols.
 *  optimized for speed; it loads in under a millisecond.
 *  fully customizable; if you know a little `statusline` syntax you can tweak it to your needs.
-*  extensive suite of themes for popular colorschemes including [solarized][23] (dark and light), [tomorrow][24] (all variants), [molokai][25], [jellybeans][26] and others.
+*  extensive suite of themes for popular colorschemes including [solarized][23] (dark and light), [tomorrow][24] (all variants), [molokai][25], [jellybeans][26] and others; have a look at the [screenshots][14] in the wiki.
 *  supports 7.2 as the minimum Vim version
 
 # Rationale
diff --git a/autoload/airline.vim b/autoload/airline.vim
index b6f368e..f89fd20 100644
--- a/autoload/airline.vim
+++ b/autoload/airline.vim
@@ -109,7 +109,7 @@ function! s:get_statusline(winnr, active)
   return sl
 endfunction
 
-function! s:exec_funcrefs(list, break_early)
+function! airline#exec_funcrefs(list, break_early)
   " for 7.2; we cannot iterate list, hence why we use range()
   " for 7.3-[97, 328]; we cannot reuse the variable, hence the {}
   for i in range(0, len(a:list) - 1)
@@ -126,7 +126,7 @@ function! s:exec_funcrefs(list, break_early)
 endfunction
 
 function! airline#update_statusline()
-  if s:exec_funcrefs(g:airline_exclude_funcrefs, 1)
+  if airline#exec_funcrefs(g:airline_exclude_funcrefs, 1)
     call setwinvar(winnr(), '&statusline', '')
     return
   endif
@@ -135,7 +135,7 @@ function! airline#update_statusline()
   for section in s:sections
     unlet! w:airline_section_{section}
   endfor
-  call s:exec_funcrefs(g:airline_statusline_funcrefs, 0)
+  call airline#exec_funcrefs(g:airline_statusline_funcrefs, 0)
 
   let w:airline_active = 1
   call setwinvar(winnr(), '&statusline', s:get_statusline(winnr(), 1))
@@ -148,7 +148,6 @@ function! airline#update_statusline()
   endfor
 endfunction
 
-let g:airline_current_mode_text = ''
 function! airline#update_highlight()
   if get(w:, 'airline_active', 1)
     let l:m = mode()
diff --git a/autoload/airline/extensions.vim b/autoload/airline/extensions.vim
index 08859f1..f7b7402 100644
--- a/autoload/airline/extensions.vim
+++ b/autoload/airline/extensions.vim
@@ -1,6 +1,28 @@
 " MIT license. Copyright (c) 2013 Bailey Ling.
 " vim: ts=2 sts=2 sw=2 fdm=indent
 
+let s:ext = {}
+let s:ext._cursormove_funcrefs = []
+function! s:ext.add_statusline_funcref(funcref) dict
+  call add(g:airline_statusline_funcrefs, a:funcref)
+endfunction
+function! s:ext.add_cursormove_funcref(funcref) dict
+  call add(self._cursormove_funcrefs, a:funcref)
+endfunction
+
+let s:filetype_overrides = {
+      \ 'netrw': [ 'netrw', '%f' ],
+      \ 'unite': [ 'Unite', '%{unite#get_status_string()}' ],
+      \ 'nerdtree': [ 'NERD', '' ],
+      \ 'undotree': [ 'undotree', '' ],
+      \ 'gundo': [ 'Gundo', '' ],
+      \ 'diff': [ 'diff', '' ],
+      \ 'vimshell': [ 'vimshell', '%{vimshell#get_status_string()}' ],
+      \ 'vimfiler': [ 'vimfiler', '%{vimfiler#get_status_string()}' ],
+      \ 'minibufexpl': [ 'MiniBufExplorer', '' ],
+      \ 'startify': [ 'startify', '' ],
+      \ }
+
 function! airline#extensions#apply_left_override(section1, section2)
   let w:airline_section_a = a:section1
   let w:airline_section_b = a:section2
@@ -9,23 +31,10 @@ function! airline#extensions#apply_left_override(section1, section2)
   let w:airline_left_only = 1
 endfunction
 
-function! airline#extensions#update_external_values()
-  let g:airline_externals_bufferline = g:airline_enable_bufferline && exists('*bufferline#get_status_string')
-        \ ? '%{bufferline#refresh_status()}'.bufferline#get_status_string() : "%f%m"
-  let g:airline_externals_syntastic = g:airline_enable_syntastic && exists('*SyntasticStatuslineFlag')
-        \ ? '%#warningmsg#%{SyntasticStatuslineFlag()}' : ''
-  let g:airline_externals_branch = g:airline_enable_branch
-        \ ? (exists('*fugitive#head') && strlen(fugitive#head()) > 0
-          \ ? g:airline_branch_prefix.fugitive#head()
-          \ : exists('*lawrencium#statusline') && strlen(lawrencium#statusline()) > 0
-            \ ? g:airline_branch_prefix.lawrencium#statusline()
-            \ : '')
-        \ : ''
-  let g:airline_externals_tagbar = g:airline_enable_tagbar && exists(':Tagbar')
-        \ ? '%(%{tagbar#currenttag("%s","")} '.g:airline_right_alt_sep.' %)' : ''
-endfunction
+let s:active_winnr = -1
+function! airline#extensions#update_statusline()
+  let s:active_winnr = winnr()
 
-function! airline#extensions#apply_window_overrides()
   if &buftype == 'quickfix'
     let w:airline_section_a = 'Quickfix'
     let w:airline_section_b = ''
@@ -46,28 +55,9 @@ function! airline#extensions#apply_window_overrides()
     let w:airline_section_c = bufname(winbufnr(winnr()))
   endif
 
-  if &ft == 'netrw'
-    call airline#extensions#apply_left_override('netrw', '%f')
-  elseif &ft == 'unite'
-    call airline#extensions#apply_left_override('Unite', '%{unite#get_status_string()}')
-  elseif &ft == 'nerdtree'
-    call airline#extensions#apply_left_override('NERD', '')
-  elseif &ft == 'undotree'
-    call airline#extensions#apply_left_override('undotree', '')
-  elseif &ft == 'gundo'
-    call airline#extensions#apply_left_override('Gundo', '')
-  elseif &ft == 'diff'
-    call airline#extensions#apply_left_override('diff', '')
-  elseif &ft == 'tagbar'
-    call airline#extensions#apply_left_override('Tagbar', '%{TagbarGenerateStatusline()}')
-  elseif &ft == 'vimshell'
-    call airline#extensions#apply_left_override('vimshell', '%{vimshell#get_status_string()}')
-  elseif &ft == 'vimfiler'
-    call airline#extensions#apply_left_override('vimfiler', '%{vimfiler#get_status_string()}')
-  elseif &ft == 'minibufexpl'
-    call airline#extensions#apply_left_override('MiniBufExplorer', '')
-  elseif &ft == 'startify'
-    call airline#extensions#apply_left_override('startify', '')
+  if has_key(s:filetype_overrides, &ft)
+    let args = s:filetype_overrides[&ft]
+    call airline#extensions#apply_left_override(args[0], args[1])
   endif
 endfunction
 
@@ -97,39 +87,55 @@ function! airline#extensions#load_theme()
   endif
 endfunction
 
+function! s:sync_active_winnr()
+  if winnr() != s:active_winnr
+    if airline#exec_funcrefs(s:ext._cursormove_funcrefs, 1)
+      return
+    endif
+    call airline#update_statusline()
+  endif
+endfunction
+
 function! airline#extensions#load()
+  " non-trivial number of external plugins use eventignore=all, so we need to account for that
+  autocmd CursorMoved * call <sid>sync_active_winnr()
+
+  " load core funcrefs
+  call add(g:airline_exclude_funcrefs, function('airline#extensions#is_excluded_window'))
+  call add(g:airline_statusline_funcrefs, function('airline#extensions#update_statusline'))
+
   if get(g:, 'loaded_unite', 0)
     let g:unite_force_overwrite_statusline = 0
   endif
+
   if get(g:, 'loaded_vimfiler', 0)
     let g:vimfiler_force_overwrite_statusline = 0
   endif
 
   if get(g:, 'loaded_ctrlp', 0)
-    let g:ctrlp_status_func = {
-          \ 'main': 'airline#extensions#ctrlp#ctrlp_airline',
-          \ 'prog': 'airline#extensions#ctrlp#ctrlp_airline_status',
-          \ }
+    call airline#extensions#ctrlp#init(s:ext)
   endif
 
   if get(g:, 'command_t_loaded', 0)
-    call add(g:airline_statusline_funcrefs, function('airline#extensions#commandt#apply_window_override'))
+    call airline#extensions#commandt#init(s:ext)
   endif
 
-  if g:airline_enable_bufferline && get(g:, 'loaded_bufferline', 0)
-    highlight AlBl_active gui=bold cterm=bold term=bold
-    highlight link AlBl_inactive Al6
-    let g:bufferline_inactive_highlight = 'AlBl_inactive'
-    let g:bufferline_active_highlight = 'AlBl_active'
-    let g:bufferline_active_buffer_left = ''
-    let g:bufferline_active_buffer_right = ''
-    let g:bufferline_separator = ' '
+  if exists(':TagbarToggle')
+    call airline#extensions#tagbar#init(s:ext)
   endif
 
-  call add(g:airline_statusline_funcrefs, function('airline#extensions#update_external_values'))
-  call add(g:airline_statusline_funcrefs, function('airline#extensions#apply_window_overrides'))
-  call add(g:airline_exclude_funcrefs, function('airline#extensions#is_excluded_window'))
+  if g:airline_enable_branch && (get(g:, 'loaded_fugitive', 0) || get(g:, 'loaded_lawrencium', 0))
+    call airline#extensions#branch#init(s:ext)
+  endif
 
-  call airline#extensions#update_external_values()
+  if g:airline_enable_syntastic && get(g:, 'loaded_syntastic_plugin')
+    call airline#extensions#syntastic#init(s:ext)
+  endif
+
+  if g:airline_enable_bufferline && exists('*bufferline#get_status_string')
+    call airline#extensions#bufferline#init(s:ext)
+  endif
+
+  call airline#exec_funcrefs(g:airline_statusline_funcrefs, 0)
 endfunction
 
diff --git a/autoload/airline/extensions/branch.vim b/autoload/airline/extensions/branch.vim
new file mode 100644
index 0000000..aa6db6e
--- /dev/null
+++ b/autoload/airline/extensions/branch.vim
@@ -0,0 +1,15 @@
+" MIT license. Copyright (c) 2013 Bailey Ling.
+" vim: ts=2 sts=2 sw=2 fdm=indent
+
+function! airline#extensions#branch#apply()
+  let g:airline_current_branch = exists('*fugitive#head') && strlen(fugitive#head()) > 0
+        \ ? g:airline_branch_prefix.fugitive#head()
+        \ : exists('*lawrencium#statusline') && strlen(lawrencium#statusline()) > 0
+          \ ? g:airline_branch_prefix.lawrencium#statusline()
+          \ : ''
+endfunction
+
+function! airline#extensions#branch#init(ext)
+  call a:ext.add_statusline_funcref(function('airline#extensions#branch#apply'))
+endfunction
+
diff --git a/autoload/airline/extensions/bufferline.vim b/autoload/airline/extensions/bufferline.vim
new file mode 100644
index 0000000..852b33c
--- /dev/null
+++ b/autoload/airline/extensions/bufferline.vim
@@ -0,0 +1,16 @@
+" MIT license. Copyright (c) 2013 Bailey Ling.
+" vim: ts=2 sts=2 sw=2 fdm=indent
+
+function! airline#extensions#bufferline#init(ext)
+  highlight AlBl_active gui=bold cterm=bold term=bold
+  highlight link AlBl_inactive Al6
+  let g:bufferline_inactive_highlight = 'AlBl_inactive'
+  let g:bufferline_active_highlight = 'AlBl_active'
+  let g:bufferline_active_buffer_left = ''
+  let g:bufferline_active_buffer_right = ''
+  let g:bufferline_separator = ' '
+
+  if g:airline_section_c == '%f%m'
+    let g:airline_section_c = '%{bufferline#refresh_status()}'.bufferline#get_status_string()
+  endif
+endfunction
diff --git a/autoload/airline/extensions/commandt.vim b/autoload/airline/extensions/commandt.vim
index 6ade032..2c55675 100644
--- a/autoload/airline/extensions/commandt.vim
+++ b/autoload/airline/extensions/commandt.vim
@@ -1,8 +1,12 @@
 " MIT license. Copyright (c) 2013 Bailey Ling.
 " vim: ts=2 sts=2 sw=2 fdm=indent
 
-function! airline#extensions#commandt#apply_window_override()
+function! airline#extensions#commandt#apply()
   if bufname('%') ==# 'GoToFile'
     call airline#extensions#apply_left_override('CommandT', '')
   endif
 endfunction
+
+function! airline#extensions#commandt#init(ext)
+  call ext.add_statusline_funcref(function('airline#extensions#commandt#apply'))
+endfunction
diff --git a/autoload/airline/extensions/ctrlp.vim b/autoload/airline/extensions/ctrlp.vim
index a082e57..b5f0ea3 100644
--- a/autoload/airline/extensions/ctrlp.vim
+++ b/autoload/airline/extensions/ctrlp.vim
@@ -26,10 +26,7 @@ function! airline#extensions#ctrlp#load_theme()
   endfor
 endfunction
 
-" Recreate Ctrl-P status line with some slight modifications
-
 " Arguments: focus, byfname, s:regexp, prv, item, nxt, marked
-" a:1 a:2 a:3 a:4 a:5 a:6 a:7
 function! airline#extensions#ctrlp#ctrlp_airline(...)
   let regex = a:3 ? '%#CtrlPlight#  regex %*' : ''
   let prv = '%#CtrlPlight# '.a:4.' %#Ctrlparrow1#'.g:airline_left_sep
@@ -39,15 +36,24 @@ function! airline#extensions#ctrlp#ctrlp_airline(...)
   let focus = '%=%<%#CtrlPdark# '.a:1.' %*'
   let byfname = '%#CtrlParrow3#'.g:airline_right_alt_sep.'%#CtrlPdark# '.a:2.' %*'
   let dir = '%#CtrlParrow3#'.g:airline_right_sep.'%#CtrlPlight# '.getcwd().' %*'
-  " Return the full statusline
   return regex.prv.item.nxt.marked.focus.byfname.dir
 endfunction
 
 " Argument: len
-" a:1
 function! airline#extensions#ctrlp#ctrlp_airline_status(...)
   let len = '%#CtrlPdark# '.a:1
   let dir = '%=%<%#CtrlParrow3#'.g:airline_right_sep.'%#CtrlPlight# '.getcwd().' %*'
-  " Return the full statusline
   return len.dir
 endfunction
+
+function! airline#extensions#ctrlp#is_statusline_overwritten()
+  return match(&statusline, 'CtrlPlight') >= 0
+endfunction
+
+function! airline#extensions#ctrlp#init(ext)
+  let g:ctrlp_status_func = {
+        \ 'main': 'airline#extensions#ctrlp#ctrlp_airline',
+        \ 'prog': 'airline#extensions#ctrlp#ctrlp_airline_status',
+        \ }
+  call a:ext.add_cursormove_funcref(function('airline#extensions#ctrlp#is_statusline_overwritten'))
+endfunction
diff --git a/autoload/airline/extensions/syntastic.vim b/autoload/airline/extensions/syntastic.vim
new file mode 100644
index 0000000..d6b386d
--- /dev/null
+++ b/autoload/airline/extensions/syntastic.vim
@@ -0,0 +1,8 @@
+" MIT license. Copyright (c) 2013 Bailey Ling.
+" vim: ts=2 sts=2 sw=2 fdm=indent
+
+function! airline#extensions#syntastic#init(ext)
+  if g:airline_section_gutter == ''
+    let g:airline_section_gutter = '%#warningmsg#%{SyntasticStatuslineFlag()}'
+  endif
+endfunction
diff --git a/autoload/airline/extensions/tagbar.vim b/autoload/airline/extensions/tagbar.vim
new file mode 100644
index 0000000..27fe0b0
--- /dev/null
+++ b/autoload/airline/extensions/tagbar.vim
@@ -0,0 +1,14 @@
+" MIT license. Copyright (c) 2013 Bailey Ling.
+" vim: ts=2 sts=2 sw=2 fdm=indent
+
+function! airline#extensions#tagbar#apply()
+  let w:airline_section_x = '%(%{tagbar#currenttag("%s","")} '.g:airline_right_alt_sep.' %)'.g:airline_section_x
+  if &ft == 'tagbar'
+    call airline#extensions#apply_left_override('Tagbar', '%{TagbarGenerateStatusline()}')
+  endif
+endfunction
+
+function! airline#extensions#tagbar#init(ext)
+  call a:ext.add_statusline_funcref(function('airline#extensions#tagbar#apply'))
+endfunction
+
diff --git a/plugin/airline.vim b/plugin/airline.vim
index 44631dc..3de3d27 100644
--- a/plugin/airline.vim
+++ b/plugin/airline.vim
@@ -48,36 +48,24 @@ call s:check_defined('g:airline_mode_map', {
       \ '' : 'V-BLOCK',
       \ })
 
+call s:check_defined('g:airline_section_a', '%{get(g:, "airline_current_mode_text", "")}')
+call s:check_defined('g:airline_section_b', '%{get(g:, "airline_current_branch", "")}')
+call s:check_defined('g:airline_section_c', '%f%m')
+call s:check_defined('g:airline_section_gutter', '')
+call s:check_defined('g:airline_section_x', "%{strlen(&filetype)>0?&filetype:''}")
+call s:check_defined('g:airline_section_y', "%{strlen(&fenc)>0?&fenc:''}%{strlen(&ff)>0?'['.&ff.']':''}")
+call s:check_defined('g:airline_section_z', '%3p%% '.g:airline_linecolumn_prefix.'%3l:%3c')
+
 let s:airline_initialized = 0
-let s:active_winnr = -1
 function! s:on_window_changed()
-  let s:active_winnr = winnr()
   if !s:airline_initialized
     call airline#extensions#load()
     call airline#load_theme(g:airline_theme)
-    call s:check_defined('g:airline_section_a', '%{g:airline_current_mode_text}')
-    call s:check_defined('g:airline_section_b', '%{g:airline_externals_branch}')
-    call s:check_defined('g:airline_section_c', g:airline_externals_bufferline)
-    call s:check_defined('g:airline_section_gutter', g:airline_externals_syntastic)
-    call s:check_defined('g:airline_section_x', g:airline_externals_tagbar."%{strlen(&filetype)>0?&filetype:''}")
-    call s:check_defined('g:airline_section_y', "%{strlen(&fenc)>0?&fenc:''}%{strlen(&ff)>0?'['.&ff.']':''}")
-    call s:check_defined('g:airline_section_z', '%3p%% '.g:airline_linecolumn_prefix.'%3l:%3c')
     let s:airline_initialized = 1
   endif
   call airline#update_statusline()
 endfunction
 
-" non-trivial number of external plugins use eventignore=all, so we need to account for that
-function! s:sync_active_winnr()
-  if winnr() != s:active_winnr
-    " prevent ctrlp statusline from getting overwritten
-    if get(g:, 'loaded_ctrlp', 0) && match(&statusline, 'CtrlPlight') >= 0
-      return
-    endif
-    call s:on_window_changed()
-  endif
-endfunction
-
 function! s:get_airline_themes(a, l, p)
   let files = split(globpath(&rtp, 'autoload/airline/themes/'.a:a.'*'), "\n")
   return map(files, 'fnamemodify(v:val, ":t:r")')
@@ -96,5 +84,4 @@ augroup airline
   autocmd ColorScheme * call airline#reload_highlight()
   autocmd WinEnter,BufWinEnter,FileType,BufUnload,ShellCmdPost *
         \ call <sid>on_window_changed()
-  autocmd CursorMoved * call <sid>sync_active_winnr()
 augroup END