I ve happily used Trac and Redmine for various personal projects.

Trac is written in Python while Redmine is written in Ruby (leveraging the Rails framework).

Redmine has built-in multiple project feature while Trac planned supporting it in 0.12 (already available in a branch).

You would also have to make your choice depending on the SCM you re planning to use:

• Redmine supports SVN, CVS, Git, Mercurial, Bazaar and Darcs
• Trac supports SVN and Mercurial (support for Git available with a plugin available on Trac Hacks).

Mantis http://www.mantisbt.org/

I used Bugzilla at another job a few years ago, but I think it s only bug tracking.

Where I m at now, we use FogBugz and it allows you to track cases, has wiki capabilities and even integrates with source control software. I believe there is a plugin architecture, but I haven t really looked at it.

However, I think it only programmed in ASP which most likely means IIS unless the Mono project has an ASP compatibility mode.

For my personal projects, where I m the only developer (and in many cases the only user), I have a self-made issue tracker that I made years ago, when the only big name in (free)issue trackers was Bugzilla, which I didn t like.

For a new multideveloper project I m working on, we re using Redmine. It s written in Ruby (on Rails) but it s easy to set up on Linux, supports a host of source control systems, has plugins and a wiki (including plugins to change the wiki syntax; I wrote one to do Mediawiki-style syntax since it was more familiar to the people using it). I don t know about it s API/integration but with plugins, odds are you can either find or write something to do what you need.

I asked this question about eleven months ago. I have been using Redmine and am pleased with the results. At the time of posting the question, Redmine didn t have an HTTP API, now it does. I have also recommended Redmine to others.

The reasons I like Redmine are:

1. Support for multiple projects
2. Integrated issue tracker, wiki, repository browser, forum and news feeds
3. HTTP API

I used trac for quite some time for a team of 4 developers. It worked well for us and provides most of the features you are looking for (integrations, wiki).

Other than that, you should look into Redmine and OTRS.

This article also gives a good review on the best open source bug trackers.