Simon’s Blog

You’ve probably already seen the news about Google’s new “cloud computing” platform known as App Engine.   As with anything in computing, there are pros and cons.   Here are what I think the major ones are; and how these will affect the decision to “use” or “not use” it.

Pros

If you use App Engine, and you can enjoy:

• Free hosting of your web application
• Zero server admin
• Automagic scaling

Google say the limits they’re putting on “free” mean you should be able to host an app that has five million page views a month.   That’s enough to see if your idea could become a useful business.

Cons

• You have to write your system using the App Engine SDK. The App Engine system is proprietary, so after you’ve written your system to use the Google APIs, it won’t run anywhere else.
• Technical issues - currently App Engine supports only a single language - Python. If Python is suitable for your uses, that’s fine.  If it’s not (e.g. if you need to use a library written in a different language)  you obviously can’t use App Engine.  Another potential issue is that the App Engine framework may be missing a key feature that you simply can’t work around.
• Google will have full access to your code, and all the details about how your application is performing.   If they wanted to, they could steal your code (or big chunks of your code), and you might never know.   That’s not a major risk if your app isn’t “important”, but if you’re trying something “big”, it could be.

Conclusion

The core value proposition that Google is putting to developers is to minimize the cost of getting started with your web app by reducing time-to-market, and completely eliminating hosting charges until your app starts to get popular.   This is a unique offering.

However, all this is at the expense of increasing costs down the road due to the cost of leaving Google should you want to move your app away to another provider or to your own hardware.    You would have to spend some engineering dollars to port your app to host it elsewhere.

So, is App Engine right for you?  Right now, it’s too early to be able to quantify all the various costs involved.  So, assuming that from a technical point of view, App Engine is a realistic option, whether or not you’ll want to use it comes down to which costs you most care about: the cost of getting started with your web app; or the cost of leaving due to lock-in effect of using Google’s proprietary, non-standards-based systems, should your app become successful.