The main technical skill currently [1] required of a Swarm user is the ability to write in at least one of following object oriented languages: Java or Objective C. Other recommended skills include the ability to use tools such as gdb and emacs. For the record, if you know C and have some form of experience in either C++ or Smalltalk, then learning Objective C should take no more than a day or so.
Here are some Objective C resources:
Objective C references List of Objective C references on the Web. Includes a 10 minute overview to Objective C that is most of what you need to know about Objective C. Originally contributed by Nelson Minar
Object-Oriented Programming and the Objective-C Language An excellent (online!) book on Objective C. This is for generic NeXT Objective C: Swarm uses GNU Objective C in addition to our defobj extensions (see defobj library in : Reference Guide to Swarm)
Unlike Objective C, the market is literally bursting at the seams with books on Java, so we merely point out a few relevant sites:
GNU and the Java language is a page run by the Free Software Foundation that details many free/open source Java tools, most notably the reimplementation of Sun's JDK: Kaffe.
JavaSoft, Sun Microsystems main Java page, and a new users section: New-to-Java Programming Center
| [1] | As we continue extend Swarm's multilanguage features, further language bindings may become available. |