Full list of authors, by number of lines in revision
0f8c6223801408375e8b9de3d9f0fb565a78e9f4 Sep 25 2013:

[ Authors from older revisions may not show up in
  newer revisions -- so continue to add names to
  this list, please do not remove. ]

Gabriel Wicke <gwicke@wikimedia.org>
Subramanya Sastry <ssastry@wikimedia.org>
Mark Holmquist <mtraceur@member.fsf.org>
C. Scott Ananian <cscott@cscott.net>
Robert Smith <rsmith@wikimedia.org>
Adam Wight <awight@wikimedia.org>
Marc Ordinas i Llopis <marcoil@wikimedia.org>
Arlo Breault <abreault@wikimedia.org>
Catrope <roan@wikimedia.org>
Brion Vibber <brion@wikimedia.org>
plancalculus <jan@monoid-it.de>
Jeff Evans <wayne.mokane+github@gmail.com>
Siebrand Mazeland <s.mazeland@xs4all.nl>
Aaron Schulz <aschulz@wikimedia.org>
Antoine Musso <hashar@free.fr>
Luke Welling <lwelling@wikimedia.org>
Neil Kandalgaonkar <neilk@wikimedia.org>
Antoine Musso <hashar@wikimedia.org>
Trevor Parscal <trevor@wikimedia.org>
Timo Tijhof <ttijhof@wikimedia.org>
Inez Korczyński <inez@wikia-inc.com>
Molly White <molly.white5@gmail.com>
Audrey Tang (au) <audreyt@audreyt.org>
Reedy <reedy@wikimedia.org>
MZMcBride <w@mzmcbride.com>
Ori Livneh <ori.livneh@gmail.com>
Adam Baso <abaso@wikimedia.org>
YuviPanda <yuvipanda@gmail.com>

A version of this list can be regenerated with the following one-liner:

git ls-tree -r HEAD | cut -f 2 | grep -E '\.(js|cc|h|cpp|hpp|c|txt|sh|php)$' | grep -v -E 'scripts|html5' | xargs -n1 git blame --line-porcelain | sed -ne '/^author /{ s/^author //; h }' -e '/^author-mail /{ s/^author-mail //; H; g; y/\n/ /; p }' | sort | uniq -c | sort -nr | sed -e 's/^[ ]*[1-9][0-9]* //'

Please see git blame for per-file information.