I've now replied to his email and to open up all this I've decided to just publish the email I sent to him here as well, so feel free to read it below. I'm not going to respond to any of the allegations against my "ulterior" motives. This is about the GPL and my copyright, nothing else.

Dear James,

I have received your email and read your blogpost concerning the copyright infringement.

The fact that this was not intentional but negligent behavior on the part of WPMU Dev does not absolve you from your responsibility as CEO of the company to put a stop to the infringing behavior, to take the necessary steps to make amend the situation and also to make sure that it does not happen again in the future.

The GPL license allows us all to combine our software writing efforts in a less restricitive manner than before. This new way of combining our efforts is not without limits and risks and as such requires a high level of own responsibility by all parties involved.

WPMU Dev has not lived up to this responsibility. It has hired a developer who created a WordPress Plugin, whereafter WPMU Dev did not check the code thoroughly to determine whether it infringed on any copyrights. After notification, WPMU Dev's response to the infringing conduct has also been unsatisfactory.

Rather than immediately ceasing the distribution of the plugin and checking the source code line for line and where appropiate adding the required copyright notices, WPMU Dev has opted to send me an amended version "inspired by yoast", requesting me to check if there is no more copyright infringement.

This is not the conduct that the GPL licence requires of its users. The GPL license -not to mention the circumstances surrounding the infringement- requires WPMU Dev to make an all out effort to make sure that there is no more copyright infringement and to provide me with the means to assure myself that this is the case. I am sure this is a time consuming exercise, as it was for me to write the initial code.

But that is not the point here: the point is that WPMU Dev infringes on my copyright and it needs to amend this situation in a professional manner as mandated by the terms and conditions of the GPL license.

This is what I require from WPMU Dev, no more and no less.

Best regards,
Joost de Valk

WPMU DEV Copyright Infringement: the story continues is a post by Joost de Valk on Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!

What happened? WPMU DEV is offering a premium WordPress SEO plugin for download, which was also offered for download on WordPress.org in a lite version. This plugin had copied large chunks of code from my own WordPress SEO plugin. Not just a couple of lines, hundreds, probably even thousands of lines were used and all they changed was the namespace in most cases. They added some functionality, but not a whole lot.

The WPMU DEV author was 100% in his right to do so, had he retained my copyright notice. It'd still be bad form and annoying Free Rider behavior, but he'd not be breaking the law. He did however, not maintain my copyright nor properly state anywhere in the plugin that my code was the source for his. Last week, when I found out, I tweeted about it. I was pissed, as you can see from that tweet. Now, a week later, I'm still mad, but also very, very sad.

WPMU DEV does a disservice to its customers

Not only does this hurt me, this is actually a disservice to WPMU DEV's paying customers. You see, the code they have in there is a few versions old and contains bugs that I already fixed in my plugin. On top of that, their customers probably wouldn't like to hear that they're paying (through their subscription) for something that they could've gotten for free somewhere else.

I got a response from them last week, stating "Cool, we'll look at it, and completely rewrite any code that may be copied. Again that's totally against our policy, so very sorry!". They didn't take the page down as they should have, instead, they are going to rewrite the code. That means new bugs and a focus on recreating something instead of creating something truly new and worth while. If I were a customer, I'd feel cheated.

All this combined made me take a next step. This morning, Incsub, the parent company of WPMU DEV, received this cease & desist letter from my lawyer. If they don't take down the page, I will press charges and seek assistance from the Free Software Foundation and possibly the WordPress foundation. I also took action to have the plugin removed from WordPress.org. I sent an email explaining the situation, and the plugin was removed instantly, for which I thank the WordPress.org team.

As you all know, my plugin is free and I make no money from it directly, other than the occasional donation, so this truly hurt my feelings. I still hope WPMU DEV resolves this quickly and in a way both kind to me and good for their users. I'll keep you up to date.

Note: while I appreciate your comments on this, do realize that this is now a legal case. If you say anything explicit about WPMU DEV or this particular case please back it up with proof, or I'll have to remove your comment.

WPMU DEV infringes on my copyright is a post by Joost de Valk on Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!

Unpacking the update.
Could not copy files.
Installation Failed.

After a bit of Googling I found a thread in the WordPress forums that contained a gem of a fix:

In the file /wp-admin/includes/class-wp-upgrader.php change this:

// Copy update-core.php from the new version into place.
if ( !$wp_filesystem->copy($working_dir . '/wordpress/wp-admin/includes/
  update-core.php', $wp_dir . 'wp-admin/includes/update-core.php',
  true) ) {

To:

// Copy update-core.php from the new version into place.
if ( !$wp_filesystem->copy($working_dir . '/wordpress-mu/wp-admin/includes/
  update-core.php', $wp_dir . 'wp-admin/includes/update-core.php',
  true) ) {

And low and behold: my automatic upgrade worked at once.

Upgrading issues with WordPress MU is a post by Joost de Valk on Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!

Migration of the data

We got a bit lucky in this project: the client had his own technical guy, who had written the previous platform himself and was willing to write a WXR exporter, so we could reasonably easily import all the posts through WXR. The issue was that some of these WXR files were about 20 MB large though, and the "normal" upload method of importing WXR's turned out to be fairly unstable.

Which is why I wrote a new Importer, based on the default WordPress import class:

This new Importer allows you to browse the local filesystem, and pick a WXR file to import:

This new Importer turned out to be a huge blessing in the process of importing 30 something blogs with a total of 29,019 posts and 46,319 comments. I'm not currently planning on releasing this importer, because of the huge amount of support that would take which I simply don't have time for.

Site wide posts and comments

Another thing that was needed on this site was a global index of all posts and comments. This was when I really found the WPMU Dev Premium package to be worth its money. The Post indexer and Comment Indexer plugins they have are really easy to use, and give you a global table you can easily query on.

Another one of their plugins that's really cool is the XML Sitemap plugin they offer, which generates an XML sitemap for every single blog. All I had to do was drop in a couple of files into a few directories and add one line to my .htaccess, how cool is that?

James Farmer of WPMU Dev has already agreed to be a guest on the upcoming podcast, so you'll hear more of these guys soon!

If you have a blog or blog network you'd like to migrate to WordPress MU, check out our WordPress Consulting services!

A Migration to WordPress MU is a post by Joost de Valk on Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!

For this project I needed some fairly simple things, that I could have used other plugins for but I wanted them to be simpler and cleaner than most plugins could do for me. One of those things was I needed to show an image for each post on the index and archive pages, if there was one, and wanted to be able to add a certain class to that.

So I wrote a small plugin called WordPress MU Attached Image, which does just that. It's use is simple, you download the attached image plugin, upload it to your mu-plugins folder, and use this in the loop in your theme:

yst_thumb('class','alt text');

Or, as in my case:

yst_thumb('alignright',get_the_title());

Now this plugin will work in a normal WordPress install too, but that's not what I wrote it for :)

Another thing I badly wanted was a plugin that would force the same permalink structure on all new blogs, and disallowed blog admins from changing them. This plugin does that, and immediately shows why I love WordPress MU development: the power it has to easily change things on tons of blogs at the same time is very cool.

It works like this: you download the fixed permalink plugin, make sure that on line 11, this reflects the permalink structure you want:

$yst_permalink_structure = '/%postname%/';

And you upload it to your mu-plugins folder. Voila: you're now the only one who can change permalink structures, and all new blogs will automatically have the right permalink structure.

You can expect more posts on WordPress MU in the coming weeks, as I dive deeper into the system. In the mean while, if you have a WordPress MU development project you'd like us to take on, contact me!

WordPress MU development, I love it! is a post by Joost de Valk on Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!