In The Toolbox – Pen & Paper


…when people say “bring a notebook” they mean “bring a laptop”, not “bring a moleskine” -- @natpryce


“Which is your favourite UML tool?” I swear by Crayola -- @jasongorman


First thing in the morning at work, after turning on my machine and taking a few gulps of coffee, the next thing I do is get out my notepad and pen. Despite all the advances in hardware and software and the plethora of apps on the market designed to aid in every office task, I still regularly use the old fashioned method of pen and paper.


By far the main use of my notebook is a list of things that either needs to be done or have caught my attention and so possibly deserve further thought or scrutiny at a later date. Sadly, when it comes to remembering what I’m (supposed to be) doing I’m like the proverbial goldfish – I find it all too easy to head off on a tangent and then lose focus on what really matters at that point. Although I have the ability to remember significant amounts code I have written in my programming career I still can’t make it to the top of the stairs at home without remembering what it was I went up there… oh, look shiny thing!


The sorts of things I end up making a note of are the questions (or quite possibly the WTFs [1]) that form in my mind as I’m working with both my own, and other people’s code. I have yet to work in an environment where code reviews happen formally, regularly and cover 100% of the codebase. Instead I tend to see what’s changed when I update my local copy, mostly out of self interest to see where any instability might arise, but also because I’m just a nosy person that likes to know what’s going on.


Most times the kind of things that raise questions are fairly isolated and so can often be resolved pretty quickly, especially if the other developer is happy to take it up there and then. The alternative is a wider issue that involves looking across the entire codebase for similar cases. For example, catching every type of exception, i.e. catch(…) in C++ or catch(Exception) in C#, is a code smell for me when not done on a module boundary and so I’d reserve a little time to review the codebase and look for similar occurrences. I probably wouldn’t want to take that on immediately, but I also don’t want to forget it either.


Naturally when trying to work in an agile kind of way one is often mindful of eliminating any waste, and these little nuggets of work are no exception. My notebook acts as a temporary store to record my observations, but at a later date they can be handled in a variety of ways. It could be that someone else has picked up on it too and it’s all resolved so I can just scribble out my note. Or perhaps what I initially thought was a smell turned out to be insignificant after all. At the other end of the scale are the items that have since mushroomed into a much larger task and so needs to be placed on the backlog as a formal piece of work – subject to further prioritisation of course. In between these two are the little things that aren’t really important enough to distract me now but I’m not quite sure whether there is any real substance to them – superficially they might seem to have value, but perhaps the cost of change could only be justified as part of some other work.


There was an interesting question raised on accu-general a few weeks back about tracking new tests that spring to mind whilst writing existing ones. In this particular instance I will use the code to record my thoughts, perhaps as a simple comment or more likely as a stub test case that shows up “inconclusive” to make it more visible. If the test is for another class outside the scope of the current feature it goes in the notebook as that’s probably a can of worms just waiting to be opened.


In essence the moment when I commit my changes is a natural barrier for me because it signifies the publishing of a single atomic, tested change in the codebase. If something needs to happen before the next commit I might as well just get on and do it. Otherwise it goes in the book and I can recalibrate my workload again afterwards. Assuming I don’t break the build of course…


When I first discovered UML and started playing with a couple of Enterprise UML tools I, like many others, thought this was going to be a Big Thing. Of course it hasn’t really panned out that way, but what I have got from it is a common vocabulary to use when knocking up diagrams. Martin Fowler uses the term “sketches” in his UML Distilled book which I prefer as it takes a lot of the formality out of their use and recasts them as what they most usefully are – a conduit for further discussion.


What I particularly like about diagrams drawn in my notebook is that they also contain all the little amendments and annotations that occurred during the discussion. While the end result might be a nice snapshot of the destination, the journey often says far more about the contention and ideas that were explored along the way. Seeing the furiously drawn circles and underlines again is a great reminder on where the points of contention were and consequently where future confusion may lie.


Then there is just the immediacy of being able to flick back a few pages to the diagram in the middle of a discussion. Nothing kills the flow more than sitting, idly waiting for someone to hunt around in their emails looking for a picture. You could of course just draw it again, perhaps slightly differently this time so that the perspective changes. That in itself is a smell – constantly referring to or drawing the same picture – as it might mean the design is unintuitive.


If you’re going to knock up a sketch it’s better still if you have a couple of different coloured pens to hand too. Even just using black and red gives you a way to call out the more important aspects. Given the wage of an average programmer it costs very little to buy your own set of pens. You might need to keep them in a locked drawer though if you ever want them to remain in your possession for longer than a few days!


Outside the usual run-of-the-mill development notes are the support ones. When in the heat of battle as I’m trying to resolve a production issue I need somewhere to jot down my observations. Often these are events that come from log files or specific data items like a unique customer ID. They often exist only transiently, appearing perhaps within the command line in my shell or a SQL query window. After the dust has settled I like to write-up a short post-mortem that explains the problem and contains the key data items in case a similar problem occurs again.


Anything that happens out of the ordinary in production has the hallmark of an edge case that will likely feed into some later development, such as a fix that requires a specific test case. Whilst a post-mortem email is readily searchable the margins of my notebook are often a quicker source when looking for some “interesting data” to put a test case together.

Post Script

My need to write things down was borne out of the frustration of forgetting things which had the undesirable consequence of me keep going off at a tangent and therefore disregarding the real priority. Sadly it took me a very long time to realise that the act of writing down notes was what mattered, not that I had actually written them. It also probably explains why I can remember much of the code I have written. This turns out to be a well known phenomenon [2] that is possibly even more effective when handwritten than typed.


The most important part of this discovery though affects my personal life. Where before I used to rely, and fail miserably, on trying to remember the hints my wife would drop for her birthday and Christmas presents; now I surreptitiously jot them down on my smart phone under the guise of sending another banal tweet. The old fashioned approach definitely works better for me in the office but in the great outdoors I’m happy to bow down to the convenience of modern technology.






Chris Oldwood

15 August 2013



Chris is a freelance developer who started out as a bedroom coder in the 80’s writing assembler on 8-bit micros; these days it’s C++ and C#. He also commentates on the Godmanchester duck race and can be contacted via or @chrisoldwood.