Lizard is open source. Lizard is intended for geographic water information websites. Lizard is written in Python and Django. Lizard isn't perfect yet and not everything is as easy to install or extend or to build upon, but we're really open source and we're working hard to make everything easier and especially neater.
The best thing about Lizard, apart from being open source, is that it is pluggable. At the core is a plugin mechanism for getting any kind of data source into Lizard and onto the map.
The gold standard for open sourciness right now is being on github. Yes, we are on github! You'll see the base lizard-ui and lizard-map Django apps and all of the plugins.
Not all plugins are perfect and not all of 'em are well-documented. But they're all there. And they all have tests. And at least a readme. Some have quite good documentation, actually!
The Python package index ("pypi") is the canonical place for Python packages. At the moment, only lizard-ui and lizard-map are there, but that's on the radar to be rectified. In the end, all Python packages ought to end up in there.
Code without documentation does not exist. For Python packages, the documentation ought to be on readthedocs.org. We haven't put the infrastructure in place yet, so for the time being you'll have to make do with doc.lizardsystem.nl, which has some non-accessible documentation on several Lizard sites, too.
Don't worry, all the documentation there will move to read the docs. As a proof-of-concept, look at sitesetup.readthedocs.org.
You can see a demonstration website at demo.lizard.net.
Open source also means individual developer's weblogs. Not all the content is always relevant to Lizard, but a lot is.
Here's a presentation that gives a pretty short explanation of Lizard from a developer standpoint:
There are quite some Lizard videos that Reinout made at video.nelen-schuurmans.nl, but these are mostly Dutch. Here are two that are English that can give you a pretty good idea.
The first is on a quite simple ground model website. The quality isn't perfect, but it shows you a very customized Lizard site. And please don't mind the I'm-about-to-move interior during the first minute :-)
The second shows a slightly older website, but one that's quite full of data.
There's no proper English-language mailinglist yet for Lizard. For the time being, for developer information, you'd best contact Reinout van Rees at firstname.lastname@example.org.
For Dutch information, including companies that work with Lizard, you'd best visit www.lizard.net.