(Hi, Smalltalk newbie here; I play around with Pharo from time to time, and thought I'd try out one of the web frameworks)
I installed Aida Web and when I try to load the Swazoo Server I get an exception somewhere in the WebSecurityManager class, which complains about the SecureHashAlgorithm class being unavailable.
Some Googling led to a suggestion that it might exist in the System-Digital Signatures package, but I couldn't find this within the Monticello browser.
Any clues?
Aida hasn't been maintaining compatibility with Pharo (or the other way around, depending on your point of view). SecureHashAlgorithm is called SHA1 in Pharo, but works largely the same. I suspect that this won't be the only problem that you're going to run into.
If you want to try anyway, you can make loading work by creating a copy of the the class SHA1 and name it SecureHashAlgorithm. To create a copy, right click on the class name in a class browser and select "copy", then provide the new name.
For completeness: the predominantly used web framework with Pharo is (probably) Seaside (there are others too which I don't know though).