[kls]

Back end technologies are becoming less and less critical in modern web development. The web is no longer chained to the server stack that is chosen. My suggestion would be to learn a RESTful API on the existing stack that you know.

Set up RESTful JSON services and build a web front end with just HTML, CSS and JavaScript. Try out Dojo and jQuery and use them to completely replace ASP.NET. Write your entire UI independent of the server stack and have it retrieve data and execute business logic via the RESTful services you stand up. Try to implement everything in HTML files with no server side scripting.

From there, you can take that knowledge to any back end stack, further once you know how to write web apps independent of the back end stack, you can learn to stand up services in other languages. Once you master this development style, it become very easy to learn a REST API on a new platform and languages so you can quickly adapt your development to whatever back end a company uses.

Further, it makes you front ends far more portable among back end architectures, Mobile becomes just another front end consuming the same REST services and HTML, CSS and JavaScript provide a far more responsive and usable application, when you liberate the UI from having to POST back to the server for every action you can create a lot of workflows that are just not possible with the old page-POST model.

[jfletch1925]

Actually, I have already done something very similar to that and I did it on the job. At one gig, we used Ext JS to create a front-end web app. This web app would make calls back to server methods written in C#. All the data was passed between the frontend and the server in JSON. It is much more modular and makes the frontend more portable as you say, but I was really more interested in getting away from doing the server side programming in the Microsoft stack. Something completely different.

[kls]

So take that same front end stack and implement your services in python, or Ruby or Java or Node.js.