How do Drigg and Pligg compare?

How do Drigg and Pligg compare?

I am Drigg's founder and developer. Drigg and Pligg are pieces of software that will allow you to create Digg-like sites. People sometimes ask me if they should pick Drigg or Pligg. When it happens, I am not sure what I should answer. This article will hopefully solve the dilemma for most of them. Please note that I am bound to be biased here. I am an ex-Pligg users, who happened to have the both the need and the skills to create an equivalent product. I would have never forked Pligg had I liked Pligg in the first place. So... well, feel free to tell me what I got wrong with facts -- I will correct this post accordingly.

Where Pligg wins

Availability of themes

  • Drigg: Very few. In fact, one. There are countless Drupal themes. However, it's not super-trivial to adapt them so that they have all of the "drigg" stuff
  • Pligg: Tons. And tons. Which is surprising, seen how themes are done.

Learning curve

  • Drigg: It's based on Drupal. So, it takes a little while to "get the hang of it".
  • Pligg: Easier than Drigg. Especially since it's so much more limited.

User base

  • Drigg: Excluding the huge Drupal user base, Drigg has a limited user base especially compared to Pligg's
  • Pligg: Huge user base.

It's easy to see why quite a few inexperienced users would pick Pligg here: it's easier to get a decent site up and running without battling a learning curve or getting lost in Drupal's configuration options. However...

Where Drigg wins

Underlying framework

  • Drigg: based on a rock-solid, award-winning CMS: Drupal
  • Pligg: not based on any particular CMS


  • Drigg: Tons and tons of [Drupal modules](See: available for Drupal.
  • Pligg: Very few modules. All the interesting ones are not free, and are sold through the "Pligg shop". The legality of this is dubious, since they are pushing users to link non-free software with GPL software


  • Drigg: Fast. The drawback is that Drigg does require a large number of queries (this is something "inherited" from Drupal). However, queries are very easily cached, and Drupal can be scaled a lot by using "memcached".
  • Pligg: slow. It does require fewer queries. However, there is no support for "memcached". So, it won't scale easily.


  • Drigg: Uses Drupal's PHPTemplate. A theme is made up of 4 basic files (plus CSS) which will be always completely independent from the program's logic
  • Pligg: Has its own templating system, with a huge "but!". Templates hold amazing amounts of logic. The code sometimes will change its logic according to the theme (!). Security fixes often require changing the templates.

Source code

  • Drigg: Very neat. It follows the Drupal coding standard. It's extremely easy to read it and extend it.
  • Pligg: Horrific. The template system holds half the software's logic. The templates are immensely complicated. The program itself is basically impossible to read, and it's immensely hard to figure out what is going on. A lot of security issues require changing the templates.

Adding extra pages

  • Drigg: Admin → Create Content → Page → Fill in the form
  • Pligg: You will need to create two files, taking one from an existing template. This is because there is no "real" CMS underneath.

Extending it

  • Drigg: There are thousands of Drupal developers out there, available for consulting. Creating modules is extremely simple. You can add blogs, forums, and pretty much anything you like.
  • Pligg: Very few people understand Pligg's code. That's no surprise. Creating modules is nowhere near as neat as Drupal's module hooking system. There is no support for blogs, forums, etc.


  • Drigg: As secure as Drupal. See: "very secure".
  • Pligg: Security problems are found consistently. Upgrading is a nightmare, because so much logic is in the template system, and security bugs are often found in the templates.

Database structure

  • Drigg: Neat. It's Drupal's, with a couple of extra tables.
  • Pligg: It's so messy that the Pligg to Drigg importer needs to guess several things, and the import doesn't always succeed.

Activity and development

  • Drigg: Active. Three programmers are working on it a lot. There are some feature requests in the queue, which are being closed.
  • Pligg: Not very active. Development has apparently stalled since Pligg's main programmer apparently left around February/March.

Politics around it

  • Drigg: Fun to work with. Tony Mobily is the maintainer, but others have joined in and are helping out immensely.
  • Pligg: The main developer left Pligg and created a competing system. According to, the Pligg team is now actively "taking" code from the main developer's SVN archive and keeping Pligg in sync (!).

Politics around it, take 2: forums

  • Drigg: Never a forum post was deleted from Drigg's forums. Ever. Well, unless they were full of links about performing better in bed!
  • Pligg: There are countless reports of Pligg's maintainer deleting unfavourable posts. Here is A fine example -- with evidence that the post actually existed.

Open source principles

  • Drigg: GPL. Always. No doubts.
  • Pligg: When Pligg was "for sale", some members of the core team stated clearly that the license might well change according to the buyer's wishes and conditions. Nobody bought Pligg.

Bug tracking

  • Drigg: Clockwork bug tracking using Drupal's system. For example, see Drigg's issues (80 issues have been reported, discussed, and closed) or EVF's issues or User Karma's issues.
  • Pligg: Bug tracking is vaguely done through the forums. A lot of bugs are never closed. There is no real tracking system for bugs.

Karma calculation

  • Drigg: Clear. The Karma subsystem written for Drigg ended up becoming the best Karma subsystem used by Drupal users, wven without Drigg.
  • Pligg: Nobody has managed, to date, to give me a detailed explanation on how the users' karma is calculated in Pligg. The code won't help you.


  • Drigg: Drigg-related issues are promptly answered in Drigg's site. Other queries that are Drupal related are answered by the huge, friendly Drupal community.
  • Pligg: Pligg's forums are active, but they are mainly crowded with people wondering where the weirdness XYZ will be dealt with.


So, what would you pick? What's your experience with Pligg? And with Drigg? I am obviously biased. If I got things wrong, please let me know... in the meantime, excuse me: I am busy maintaining my great software project!



AshDigg's picture
Submitted by AshDigg on

I'm the ex-lead dev for Pligg and the new lead dev for a Pligg fork... Social Web CMS Many, if not all, of Tony's observations are correct. At Social Web CMS we agree with Tony on many of the points and are working to fix them.

Our first focus is on bug and security fixes followed by performance. There will be some new features along the way based upon community feedback. Security patches will be made available immediately. Anyone who wants to help contribute will be welcomed. The idea is to have a happy, helpful community.

admin's picture
Submitted by admin on


Thank you Ash :-D
I look forward to see the first release of Social Web CMS!

Competition is good :-D



kn0thing's picture
Submitted by kn0thing on

Thanks for the thorough write-up. Though, I'm curious to know what you think of reddit as an open source alternative? (Or simply as a platform vis a vis user-created reddits).

Tony Mobily's picture


As I told Dave, if Reddit had released their system a little earlier (say November 2007), Drigg wouldn't exist, FSDaily would be a Reddit site, and I would know Python.

In fact, I think today it's either Reddit or Drigg -- it depends on what you want to do. Drigg is immensely more flexible. Bur Reddit is definitely better if what you want to do is... well, a purely "voting" site ala Digg.

But it's a lot harder to configure. If a lot of people stopped in fear in front of Drigg...


Andrew Min's picture
Submitted by Andrew Min on

It might be a good idea to add a section on Reddit. I do think that one problem with Reddit is that it's very lightweight. That's good for speed, but it's also a tad low on features, especially compared to Drigg.

Andrew Min

SteveHo's picture
Submitted by SteveHo on

Tony you should do more research before you write such a blatantly biased article. I monitor pligg's code updates from twitter and both changes and additions are made almost daily.

The security issues you mention could have only been caused by pligg's former lead developer Ashdigg, so that should tell you how secure this fork is going to be.

As mentioned on pligg's blog, they even had to hire an outside security expert to fix all Ashdigg's mistakes. I'm beginning to think that the true story is that AshDigg was fired from pligg.

Tony Mobily's picture



1) You entitled your post "false facts" (!)

2) You did NOT provide a list of false facts or corrections

3) You mention that you monitor Pligg's changes. It may be changing *now*, but I know for a fact that Pigg's SVN stalled on February.

4) You blame the security problems on Ash. Ash was *the* previous maintainer of Pligg. Of course it was his fault! The same applies to me: of course Drigg's bugs are my fault! However, I would find it *immensely* annoying if I quit a project, and people blamed every problem on *me*

5) As far as I've _seen_ (say it with me: "seen"), Pligg fixed its security problems only by copying what Ash had done to his fork. Please provide a link to the code changes made by this security expert -- and please don't mention any changes which match what Ash had done a day or so earlier

6) Fired...?!? You entitle your post "False Facts" and then start a speculation about a free software project _firing_ its maintainer and main coder? Oh dear...

Guys, _facts_. Show me that Pligg's code is not a humongous mess. Show me that the modules in the "Pligg shop" don't break the GPL. Tell me how karma works in Pligg. Show me that Pigg's database structure is not ^%^$%$%. Show me that the post deletion happening on the forums is a huge conspiracy theory. Tell me which part of what I wrote is wrong.



onet's picture
Submitted by onet on

is there a dedicated support site for Drigg? I can't seem to find anything current. Most of the search results show post that are at least 2 years old. I'm having problems with a new install and need some direction. Thanks.

petsagouris's picture

There is a strong competitor in the social cms scene. The name is HotaruCMS, I suggest you update the article and add some information about it.
You can find it here:

Author information

Tony Mobily's picture


Tony is the founder and the Editor In Chief of Free Software Magazine