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The Better Code Book – Our MVPs of 2015

We firmly believe spaghetti belongs on the dinner table and not in code. Our mission when starting NDepend was to create a tool to make best coding practices easier to maintain and improve. Writing has always been part of our message (see Patrick Smacchia’s work on CodeBetter.com) and we are proud to present our favorite pieces of writing from around the web in the last year, collected in what we are calling the Better Code Book.

We wanted to focus not only on how people use NDepend to improve their code for developers and architects, but also how to use static analysis in a broader, management sense. We are extremely grateful for our contributors in this project. Let us introduce them:

Bjørn Einar Bjartnes is a developer at the Norwegian Broadcasting Corporation. His current role is a backend developer at the API team, serving web, mobile, TV clients and more metadata about programs- and video-streams. He holds a MSc in Engineering Cybernetics and has a background from the petroleum industry, which has probably shaped his view on systems design. Also, Bjørn is active in the local F# Meetup and a proud member of the lambda club, playing with all things useless related to computers. You can also follow him on Twitter: @bjartnes

Jack Robinson is a twenty-something student in his final year of a degree in Software Engineering at Victoria University of Wellington. Currently an Intern Developer at Xero, he enjoys writing clean code, playing a board game or two with his friends, or just sitting down and watching a good film. You can read not just his musings on computer science, but also reviews on films and more at his website jackrobinson.co.nz

Prasad Narravula is a programmer, architect, consultant, and problem-solving leader.  He helps teams in agile development essentials- feedback loops to fail fast, enabling (engineering) practices, iterative and incremental design, starting at the right place, discovery, and learning. When time permits, he writes at ObjectCraftworks.com.

Erik Dietrich, founder of DaedTech LLC, is a programmer, architect, development coach, writer, Pluralsight author, and technologist. You can read his writing and find out more about him at http://www.daedtech.com/ and you can follow him on Twitter @daedtech.

Anthony Sciamanna is a software developer from Philadelphia, PA who has worked in the industry for nearly 20 years. He specializes in leading and coaching development teams, improving development practices for cross-functional teams, Test-Driven Development (TDD), unit testing, pair programming, and other Agile / eXtreme Programming (XP) practices. He can be contacted via his website: anthonysciamanna.com

Tomasz Jaskula is a software craftsman, founder and organizer of Paris user groups for F# and Domain Driven Design. He focuses on creating software delivering true business value which aligns with the business’s strategic initiatives and bears solutions with clearly identifiable competitive advantage. He is currently working for a big French bank building reactive applications in F# and C#. In his free time, he runs a startup project on applying machine learning with F# to the recruitment field, speaks at conferences and user groups, and writes blogs and articles for a French magazine for coders called “Programmez !” You can visit his site jaskula.fr

Continue reading The Better Code Book – Our MVPs of 2015

NDepend in visual studio

Put a Little NDepend in your Visual Studio

The software development world is filled with what I think of as “Coke-Pepsi” debates. This is how my brain categorizes debates over preference that are almost entirely subjective. There is no right or wrong answer to “is Coke or Pepsi better?” The answer is, “whichever one you like better.”

Examples abound in the software world. Should you use a heavyweight IDE or a lightweight text editor? Which OOP language is ‘the best?’ And, speaking of OOP, should you use an OOP language at all, or should you use a functional one? Pascal casing or camel? The list goes on, but these sorts of things generally boil down to the comfort and preferences of the person or team.

It would be tempting to paint NDepend Standalone versus NDepend’s Visual Studio plugin with this brush. And, while I think you could make a pretty legitimate case that this too, is simply a matter of preference, I’d like to do a thought exercise today in which I lobby in favor of the integration approach. In my opinion, there are enough advantages that I might be able to sneak this one out of the Coke-vs-Pepsi realm. Continue reading Put a Little NDepend in your Visual Studio

calculating ROI of NDepend

Calculating the ROI of NDepend

Years ago, I discovered NDepend and downloaded it for a trial.  At the time, I found myself working in a .NET shop where a lot of developers worked in the same large WPF codebase.  Code reviews were mandated, debates were frequent and impassioned, and global variables were everywhere, to the dismay of only some of us.  There was an entrenched majority that favored (or at least didn’t mind) a highly procedural style of writing object-oriented software, and nobody seemed able to put their fingers on why most feature development there had slowed to a crawl.

I was new to the group and had to pick my battles, particularly with people that had been there a long time.  Developers who favored automated testing and craftsmanship principles were in the minority there and had a history of leaving out of frustration, so I knew it’d be a challenge, and I went looking for help.  Among other things, I found NDepend and, after installing a trial, I recognized the power of the tool.

I recognized that it could help me as an objective, unbiased partner in making my arguments, but I also recognized that the way I approached code and architecture would never be the same.  The ability to visualize architecture in real time, the ability to treat code as queryable data, the metrics, the statistics, the well thought-out code warnings… it was a game-changer for me.  I just needed to convince my manager to let me spend a few hundred dollars to convert my trial version into a paid version.

It turned out this wasn’t hard, at least for me.  I had the good fortune of working for a company that appropriated a tools and learning budget for each individual developer, meaning all I had to do was declare that I wanted some of my total spend to go toward NDepend.  I did it without blinking.  But it might be that you aren’t as lucky.  Maybe you find yourself in a similar position to mine back then, but wanting to convince your manager that this powerful tool is indispensable because you don’t have a discretionary tools budget.

ROI: The Language of Management

I think I can help you here.  After all, I did leverage my experience running an IT department into a Plurlasight course about how to lobby your managers for practices and tools.  And the key to making a business case for anything, NDepend included, is to talk in terms of profits and losses, rather than in terms of, “it’s awesome, and it has all these graphs, and it shows me these rules, and CQLinq is the coolest thing ever, and…”  You get the idea.  NDepend’s coolness factor isn’t going to convince your manager to buy it for you.

Continue reading Calculating the ROI of NDepend

The Case for the NDepend Dashboard Feature

If you hang around agile circles long enough, you’re quite likely to hear the terms “big, visible chart” and “information radiator.”  I think both of these loosely originate from the general management concept that, to demonstrably improve something, you must first measure and track it.  A “big, visible chart” is information that an individual or team displays in, well, big and visible fashion.  An information radiator is more or less the same concept (I’m sure it’s possible for someone who is an 8th degree agile black belt to sharp-shoot this, but I think you’d be hard pressed to argue that this isn’t the gist).

Big, Visible Information Radiators

As perhaps the most ubiquitous example imaginable, consider the factory sign that proudly displays, “____ days since the last accident,” where, hopefully, the blank contains a large number.  A sign like this is far from a feel-good vanity metrics; it actually alters behavior.  Imagine a factory where lots of accidents happen.  Line managers can call meetings and harp on the importance of safety, but probably to limited effect.  After all, the prospect of a floor incident is abstract, particularly for someone to whom it hasn’t ever happened.

But if you start putting a number on it, the concept becomes less abstract.  “Currently we have an incident every day, but we want to try to make it happen only once per month, and we’re going to keep track.”  Now, each incident means that the entire factory fails each and every day, and it does so visibly.  Incidents go from “someone else’s problem that you hear about anecdotally from time to time” to “the thing that’s making us fail visibly.”  And then you’ll find that doing nothing but making the number very visible will actually serve to alter behavior — people will be more careful so as not to be responsible for tanking the team’s metrics.

Continue reading The Case for the NDepend Dashboard Feature

NDepend updated to Version 6.2

NDepend version 6.2 has just been released. We have addressed over 20 bug fixes, including a blocker one for Visual Studio 2015 update 1 Git Controls.

More specifically the new Visual Studio 2015 Update 1 Git controls in the Visual Studio status bar were interacting with the NDepend Visual Studio extension status bar control. As a consequence this was provoking VS UI freezing. That is fortunate that the Visual Studio team warned partners (VSIP) a few weeks ago that they were adding controls to the status bar. The issue was coming from a synchronous usage of the WPF dispatcher to implement the NDepend progress & status circle. Invoking the dispatcher asynchronously fixed the issue.


We also stumbled on an unusual issue due to an unfixed Windows bug. When working with DataGridView with many rows (like 1000+) we can face an unmanaged StackOverflowException that crashes the process. The Windows bug is explained here http://stackoverflow.com/a/14716720/27194 and as far as we know it is not fixed. The problem occurs only when the Windows process TabTip.exe runs (“Touch Keyboard and Handwriting Panel Service“) and the stackoverflow link explains that the only way to prevent it is to disable this touch keyboard service. We’re going the hard way and actually when NDepend starts, it now tries to kill this process. Most of the time it’ll work, even if the Windows user is not administrator. If you get any inconvenience with this rough fix, please let us know.

Apart these two fixes, many other bugs were fixed and some improvements were added (see the complete list here). Bugs fixed also includes some incorrect results that were happening because the way Roslyn emits IL has significantly changed in some situations, and NDepend relies a lot on IL code analysis.




Let’s Build a Metric: Using CQLinq to Reason about Application State

I’ve been letting the experiments run for a bit before posting results so as to give all participants enough time to submit, if they so choose.  So, I’ll refresh everyone’s memory a bit here.  Last time, I published a study of how long it took, in seconds (self reported) for readers to comprehend a series of methods that varied by lines of code.  (Gist here).  The result was that comprehension appears to vary roughly quadratically with the number of logical lines of code.  The results of the next study are now ready, and they’re interesting!

Off the cuff, I fully expected cyclomatic complexity to drive up comprehension time faster than the number of lines of code.  It turns out, however, that this isn’t the case.  Here is a graph of the results of people’s time to comprehend code that varied only by cyclomatic complexity.  (Gist here).


If you look at the shape of this graph, the increase is slightly more aggressive than linear, but not nearly as aggressive as the increase that comes with an increase in lines of code.  When you account for the fact that a control flow statement is also a line of code, it actually appears that conditionals are easier to comprehend than the mathematical statements from the first experiment.

Because of this finding, I’m going to ignore cyclomatic complexity for the time being in our rough cut time to comprehend metrics.  I’ll assume that control flow statements impact time to comprehend as lines of code more than as conditional branching scenarios.  Perhaps this makes sense, too, since understanding all of the branching of a method is probably an easier task than testing all paths through it.

As an aside, one of the things I love about NDepend is that it lets me be relatively scientific about the approach to code.  I constantly have questions about the character and makeup of code, and NDepend provides a great framework for getting answers quickly.  I’ve actually parlayed this into a nice component of my consulting work — doing professional assessments of code bases and looking for gaps that can be assessed.

Going back to our in-progress metric, it’s going to be important to start reasoning about other factors that pertain to methods.  Here are a couple of the original hypotheses from earlier in the series that we could explore next.

  • Understanding methods that refer to class fields take longer than purely functional methods.
  • Time to comprehend is dramatically increased by reference to global variables/state.

If I turn a critical eye to these predictions, there are two key components: scope and popularity.  By scope, I mean, “how closely to the method is this thing defined?”  Is it a local variable, defined right there in the method?  Is it a class field that I have to scroll up to find a definition of?  Is it defined in some other file somewhere (or even some other assembly)?  One would assume that having to pause reading the method, navigate to some other file, open it, and read to find the definition of a variable would mean a sharp spike in time to comprehend versus an integer declared on the first line of the method.

And, by popularity, I mean, how hard is it to reason about the state of the member in question?  If you have a class with a field and two methods that use it, it’s pretty easy to understand the relationship and what the field’s value is likely to be.  If we’re talking about a global variable, then it quickly becomes almost unknowable what the thing might be and when.  You have to suck the entirety of the application’s behavior into your head to understand all the things that might happen in your method.

I’m not going to boil that ocean here, but I am going to introduce a few lesser known bits of awesomeness that come along for the ride in CQLinq.  Take a look at the following CQLinq.

If your reaction is anything like mine the first time I encountered this, you’re probably thinking, “you can do THAT?!” Yep, you sure can. Here’s what it looks like against a specific method in my Chess TDD code base.


The constructor highlighted above is shown here:


As you can see, it has one parameter, uses two fields, and assigns both of those fields.

When you simply browse through the out of the box metrics that come with NDepend, these are not the kind of things you notice immediately.  The things toward which most people gravitate are obvious metrics, like method size, cyclomatic complexity, and test coverage.  But, under the hood, in the world of CQLinq, there are so many more questions that you can answer about a code base.

Stay tuned for next time, as we start exploring them in more detail and looking at how we can validate potential hypotheses about impact on time to comprehend.

And if you want to take part in this on going experiment, click below to sign up.

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