This article originally appeared on the programmers.stackexchange blog
I wrote this quite a long time ago now (in dev years, at least). I'm not sure I 100% agree with everything I put here, but I'm keeping it around for posterity.
I always find it fairly amazing how many questions appear on programmers.se, and stackoverlow, with the subject of "Which x is better?". Equally, I've been involved in a conversation with co-workers and friends on many occasions where the subject line starts with "What do you think of x?". The commonality of these two separate threads is that the x is always a language, framework, or tool.
I want to go out on a limb here, and state my conclusion at the start of my essay:
Learning a new tool does not make you a better developer. Learning a new technique makes you a better developer, tools are just there for convenience.
I'll start with an example from my own experience. I started off as an ASP.NET WebForms developer straight out of University. I quickly became very knowledgable about the framework itself, learning how to force it to work for any edge-case I needed, and learning how to build extensions and re-use previous components effectively. I considered myself a talented developer, and was considered to be very highly skilled by my employers. Upon reflection, it is now clear to me that I was a terrible developer.
After a while, the ASP.NET MVC framework was publicly released, to much fanfare. I scoffed, safe in the knowledge that I could make any website faster, and with more functional stability, than any other developer that I knew could develop things in the MVC framework. I began to learn MVC, and being unused to the pattern, struggled to really understand the principles behind how to develop on it. I was a brilliant ASP.NET WebForms developer; I was a terrible developer.
Eventually, I came to the realisation that the MVC framework was not ideal. It had some clunky and unwieldy features (such as Microsoft AJAX), and, while it could lead to very clean code, it often did not. It was around this point that I began to learn NUnit, and the principles of TDD; I quickly became a Unit Testing aficionado, and the code I produced jumped up in quality.
At around the same time as learning TDD, I began to investigate the Agile methodologies, and how they could help my development skills. This was the real turning point; I started using my own little Kanban board to manage a project backlog, and watched the quality jump again due to the increased visibility of what I would be building and the increased ability to group tasks with other important tasks. I'd used a technique that I'd never considered to be part of development, as it was neither a tool nor a language, to improve what I was developing. I had learned how something worked, not just how to use something, and it had made my code better.
This brings me back to my initial conclusion. It's clear to me, in retrospect, that I have progressed as a developer not by learning how to use ASP.NET MVC, or how to use jQuery, or how to use node.js, but by delving a little deeper; learning how to apply the MVC pattern in a different language with different principles; learning how the underlying framework of WebForms really interacts with the web browser, not just how to write a custom datepicker control.
It's very easy to get entranced by a new tool. Perhaps you're enamoured by the features of a framework, being certain it'll let you build your apps faster, or more robustly. Or perhaps you're certain that Silverlight will let you build perfectly acceptable rich client applications without having to learn a new language. I've done it myself many times. The trick is to realise that, yes, new frameworks are great, and you should broaden your horizons as much as possible. Just don't forget that frameworks are transient, and tools become outdated.
We can really see this attitude at work in the recruitment area of the IT industry. Every job advert I've seen in the past year has "$language$ developer required", or "$framework$ developer required" as its title, and contains a list of frameworks and tools that you are expected to have at least 3 years of experience in using. What recruiters and HR managers cannot seem to understand is that each and every framework, tool, and language, has a number of parallels.
Let's take C# for an example. Yes, C# is very Microsoft-centric, and the .NET framework has a specific set of tools you're likely to use, NUnit for example. However, at its heart, C# is very similar to Java. Yes, you're going to declare an anonymous function in a completely different way, and you're going to use JUnit, as opposed to NUnit, but any C# developer worth his salt should become fully operational in Java in a very short period of time.
On the other hand, your average C# developer may well struggle with Ruby, for example. Dynamic languages and static languages are so different in usage that they require totally different techniques and patterns to use. Dependency Injection? Don't really need that in a dynamic language. Interfaces? Nah, not like you're used to.
How do we fix this problem? Well, there are a number of root issues here. The first is developers truly believing that being intimately familiar with, say, rails, makes them a good developer. We fix that by encouraging newer devs to be multi-disciplinary. I firmly believe that the best way to enact change in such a broad area as development is from the bottom; if every new developer comes into the game believing that they need to be familiar with more than just the language, and framework, that's directly in front of their face all day at work then many of them will go out of their way to learn a broader range of techniques, instead of just learning their framework of choice blmore intimately, or new a framework every now and again.
The second issue is the issue of organisational change. Most development houses do just one framework, and are very keen to continue to do so. On one hand this makes perfect sense, why change what already works? I recently had a conversation with a developer at another organisation about node.js: he claimed that node.js was perfect for every use case, I assured him that it was not. This attitude of one-size-fits-all is problematic, as developers in small companies aren't going to be exposed to the broader range of approaches you'll see in large companies where they recognise that sometimes you want your backend system to be written in a different manner to your API. This is, again, something that needs to come from the bottom. If you're pushing your own boundaries, discovering new techniques, you'll begin to learn which are the most appropriate for which scenario. Don't always punt for the new and shiny, try and keep a level head and really think "do I want to use this tool because it's the best thing for the job, or because I want to use it".
The final issue is hiring. This one can only change from the top, so I implore those of you who are in a position to influence the hiring process in your organisation to look at a developer's skills, not just their resumé. It still surprises me that most development houses either don't have a development test, or have one that only deals with their core technologies, not the skills that lie behind their use. It would be amazing to see a community resource containing not just a list of "good questions" to ask, but of good skills to look for, and how to look for them effectively.
So, I've spoken about how I've developed as a programmer not by learning new languages, but by pushing my boundaries in other ways with new management techniques and improving my understanding of the underlying principles of the languages I do know. I hope that a few people who read this can look at their own skills and think "you know, I understand how to use this, but do I understand why?". Real change is slow and difficult to enact, but in such a young, and social, industry we have an incredible opportunity to make changes as a community.
 I have seen developers write five thousand line actions inside a controller, through both laziness and lack of knowledge. Those of you with MVC knowledge should shudder at the though.
 Don't get me wrong, I've not yet hit the pinnacle of my development abilities, I doubt I'm anywhere near (or that I will ever really get there). Everyone has more skills to learn, myself included, and I dedicate a large amount of time to investigation of new things, and practise of the old.
 I once had a fairly involved argument with a colleague about whether Silverlight was worth using. I, unfortunately, lost, and the now-legacy Silverlight app has caused a myriad of deployment issues and at least one developer to leave the organisation.
 I particularly love ones that are "$cms$ developer required". Those go straight into my trash.
 Yes, C# has the dynamic keyword. No, that doesn't make it dynamic; dynamic in C# is just a slightly more ducky version of var.
 Batch processes was where I finally won that one. Anyone writing enterprise-sized batch processes in node.js has a serious case of myopia, in my opinion.
 I recently went to an interview where the only technical question I was asked was "What is the difference between "visibility: hidden" and "display: none" in CSS. This is not an accurate gauge of anything.