(Sharing my thoughts again)
I have invested in building up c/c++, java and c# skills over the last 15 years. On a scale of 1 to 100%, what are the stability/shell-life or “churn-resistance” of each tech skill? By “churn”, i mean value-retention i.e. how much market value would my current skill retain over 10 years on the job market? By default current skill loses value over time. My perl skill is heavily devalued (by the merciless force of job market) because perl was far more needed 10 years ago. I also specialized in DomainNameSystem, and in Apache server administration and Weblogic. Though they are still used everywhere (80% of web sites?) behind the scene, there’s no job to get based on these skills — these system simply works without any skillful management. I specialized in mysql DBA too, but except some web shops mysql is not used in big companies where I find decent salary to support my kids and the mortgage.
In a nutshell, Perl and these other technologies didn’t suffer “churn”, but they suffered loss of “appetite” i.e. loss of demand.
Back to the “technology churn” question. C# suffers technology churn. The C# skills we accumulate tend to lose value when new features are added to replaced the old. I would say dotnet remoting, winforms and linq-to-sql are some of the once-hot technologies that have since fell out of favor. Overall, I give c# a low score of 50%.
On the other extreme I give C a score of 100%. I don’t know any “new” skill demanded by C programmer employers. I feel the language and the libraries have endured the test of time for 20 to 30 years. Your investment in C language lasts forever. Incidentally, SQL is another low-churn language, but let’s focus on c#/c++/java.
I give C++ a score of 90%. Multiple-inheritance is the only Churn feature I can identify. Template is arguably another Churn feature — extremely powerful and complex but not needed by employers. STL was the last major skill that we must acquire to get jobs. After that, we have smart pointers but they seem to be adopted by many not all employers. All other Boost of ACE libraries enjoyed much lower industry adoption rate. Many job specs ask for Boost expertise, but beyond shared_ptr, I don’t see another Boost library consistently featured in job interviews. In the core language, until c++11 no new syntax was added. Contrast c#.
I give java a score of 70%. I still rely on my old core java skills for job interviews — OO design (+patterns), threading, collections, generics, JDBC. There’s a lot of new development beyond the core language layer, but so far I didn’t have to learn a lot of spring/hibernate/testing tools to get decent java jobs. There is a lot of new stuff in the web-app space. As a web app language, Java competes with fast-moving (churning) technologies like ASP.net, ROR, PHP …, all of which churn out new stuff every year, replacing the old.
For me, one recent focus (among many) is C#. Most interesting jobs I see demand WPF. This is high-churn — WPF replaced winforms which replaced COM/ActiveX (which replaced MFC?)… I hope to focus on the core subset of WPF technologies, hopefully low-churn. Now what is the core subset? In a typical GUI tool kit, a lot of look-and-feel and usability “features” are superstructures while a small subset of the toolkit forms the core infrastructure. I feel the items below are in the core subset. This list sounds like a lot, but is actually a tiny subset of the WPF technology stack.
– MVVM (separation of concern),
– data binding,
– asynchronous event handling,
– dependency property
– property change notification,
– routed events, command infrastructure
– code-behind, xaml compilation,
– runtime data flow – analysis, debugging etc
An illuminating comparison to WPF is java swing. Low-churn, very stable. It looks dated, but it gets the job done. Most usability features are supported (though WPF offers undoubtedly nicer look and feel), making swing a Capable contender for virtually all GUI projects I have seen. When I go for swing interviews, I feel the core skills in demand remain unchanged. Due to the low-churn, your swing skills don’t lose value, but swing does lose demand. Nevertheless I see a healthy, sustained level of demand for swing developers, perhaps accounting for 15% to 30% of the GUI jobs in finance. Outside finance, wpf or swing are seldom used IMO.