In my opinion, there are key events that happen that shape the future of web development.  The move to Web 2.0 and ajax, was a little tremor compared by the Factor 10  on the Richter scale announcement of Aptana’s Jaxer server.  I have always found having to develop javascript client side, C# / PHP / ASP or some other technology server side annoying.  Having to replicate the same validation in different languages and having to write data conversion layers to get data in either json or xml format just so the client can use it annoying, a pain to maintain and a waste of development time.

Enter Jaxer, essentially server side javascript processing but on steroids.  With Jaxer, you can write in the single html page, javascript that can run on either the client, the server or both, server side code is never sent to the client browser enabling you to hide your intellectual property and the workings of you API.  Any javascript library that can run client side can be used server side as well and they have added server side libraries for writing to files, socket communications, database access and web based communication. The Client can even make callbacks to server side functions simply by setting function.name.proxy = true, and Jaxer will create an Ajaxy stub client side making the server side call available to the client.

It is implemented using the mozilla firefox 3 javascript and dom engine, and a large proportion of the interpreter is C++ code, so performance should be good.  I would love to see some performance stats that compare it against php / asp / etc , but haven’t come across any yet.  If Aptana have got the performance nail hit on the head, this really will be the future of Rich Internet application development.