How to Get a MediaWiki Bug Fixed

Mark A. Hershberger

Who am I?

A really great guy!


First – and only! – Bugmeister for WMF

(They've since changed the title to Bug Wrangler)

Former member of MediaWiki Release Team

Mark y Markus (in the process of being disolved)

MediaWiki Consultant

Have a bug.

This is the easy part.

Find something that doesn't work in MediaWiki.

Especially easy if you use a new feature currently being worked on.

Three scenarios

FATAL errors – everyone can agree on these

Persistence required – These can last for years, sometimes being resolved without anyone noticing.

You may have to solve it yourself.

FATAL error

Friday, Jan 9, 2015 10:18pm

Fatal Error: Call to a member function disable() on a non-object


Code that caused this was last touched in 2004!

original commit to GlobalFunctions.php ancient-code-commit.png

Patch to fix is created the next business day

Monday, Jan 12, 2015 4:50pm fatal-fix.png

This is how bug-fixing should work

But rarely does…

Persistence required

Autogenerated XML schema

May 7, 2008


January 31, 2010


About 1.5 years

The bug is crushed and revived

June 25, 2014 – January 1, 2015


But a solution has already been given, in disguise.

Back in Oct 4, 2012


January 5, 2015


Start to Finish

2434 days

You may have to solve it yourself

Even if the problem is in core

File a bug report.


The bug may be questioned.


This can be a bit depressing, but don't give up.

You can try to solve it yourself.

You may find something you didn't expect!

Reframe your bug to better describe the problem.


Find a solution.

If you've given more details, it may help someone else provide a solution if you don't know how.

Submit it.


Refine it.

Give feedback quickly.


They're working with you to solve the bug

It is in your interest to make it happen.

It may take more time than you expected.

Your bug is fixed


Time to celebrate!



Fixing wiki bugs takes patience and thick skin.



Created with Emacs, org-mode, and reveal.js