Sunday, 6 April 2014

Ranting About Retrospectives

Following on from Thinking About Code, I have since participated in a retrospective and the introspective process has inspired me to rant :)

Free Your Mind

One of the problems we had in our last retrospective was we were very much unprepared. Many of us did not have proper notes and worst of all there was a negative mindset toward the whole retrospective process. This time around everyone actively prepared and everyone was onboard with the idea of using the retrospective to improve the way we work. A positive viewpoint really works wonders and resulted in a much higher quality of the discussion :)

Bricks Without Clay

As the famous Sherlock quote goes, you can only put theories together when you have data. This principle holds true for any scientific process, including retrospectives. This is computer science we are dealing with after all!

In our case, data is as simple as our likes and dislikes about our work. However as there is a month between our retrospectives, forgetfulness is a major issue. Ongoing observation is the key here, we all need to constantly seek out analyse the way we work. This can be as simple as jotting down notes on what you feel is good/bad as you work. 

Get To The Point

Open ended questions like "what did you like/dislike this month?" are great for getting people to open up but can lead to rambling. In an ideal world you want everyone to distill their feelings beforehand and provide short and sweet summaries. The key is to move beyond raw emotions and use unambiguous statements: "I don't like rambling" is better stated as: "I like people being concise".

Mixing It Up

When undergoing the process of self reflection, it is important to have compare and contrast against others. Trying to view things from an outsider's perspective can throw into light problems/opportunities you would have otherwise missed. In our case, reviewing a piece of code written by an applicant threw up a lot of interesting viewpoints.


Overall I feel that retrospectives are having a positive effect on the team and the change in mentality is very refreshing. We are all looking at ways to better ourselves, both individually and as a team. The next steps are to achieve the things we have talked about, which is always easier said than done.

Wednesday, 12 March 2014

Thinking About Code

Last night I dragged my colleague Simon to the monthly LSCC Round Table and we had some interesting conversations around the topic: "how to balance time between discussing code and actually coding". The session was enlightening and we ended the night with a lot of food for thought (to supplement all the pizza and soft drinks provided by our wonderful hosts xD).

The original premise for the discussion came from a feeling within our team that we were doing retrospectives too often. Assuming that nothing "bad" has happened lately, was it necessary to hold a retrospective? Would forcing a retrospective simply push people to artificially discuss arbitrary topics for the simple sake of it?

We need more data to make a proper judgement but it is clear that there is more we can do to benefit from our retrospectives. One of the obstacles in our way could be a misperceived purpose of a retrospective: a process through which to fix problems. Whilst this is an aspect of retrospectives, if we look at how others do retrospectives it quickly become apparent that the focus is primarily on gathering feedback. Even when things are going well, there is bound to be something that could be improved, nobody is perfect after all!

Contrary to this, changing simply for the sake of change can be a waste of time. Identifying the right areas/processes to change is hard. In our case it very much feels like we need to prepare better for our retrospectives and do more to facilitate the discussions inside them. There is a wealth of material out there on retrospective facilitation but Tom's blog post on the 7 pillars of agile and spiderweb retrospective caught my eye.

As mentioned, it is very early days for our team as we only had two retrospectives since we changed the format and it would be premature to apply any changes as a knee jerk reaction. Going back to the very core of the issue, we have to ensure everyone understands the purpose of the retrospective. Once everyone has the same mindset, we can start evolving the process from there :)

Credit to from which I got the typing monkey image :)

Tuesday, 4 February 2014

Skimmer's Guide - Head First Design Patterns - Welcome To Design Patterns

“The best way to use patterns is to load your brain with them and then recognize places... where you can apply them. Instead of code reuse, with patterns you get experience reuse.”


I'm reading Head First Design Patterns along with a few others in the LJC Book Club. As we read, I'll produce a series of Skimmer's Guide posts for each significant section of the book. The previous section, on the Introduction, is here. If you are interested, please join the discussion on our Google+ community.


Continuing from the introduction, we now take a deep dive into the world of design patterns. Emphasis is on the ethos that "someone had already solved your problems" and how we can reuse the experience of others. Design patterns are our way of standing on the shoulders of giants!

Keeping with the Head First method, there are many lessons and even more ways to make the knowledge stick inside your brain. We may only cover the Strategy Pattern and general design concepts but you can rest assured you will remember all of it!


Exercise - Coding Ducks! (Strategy Pattern - p.18)
This simple exercise gives us our first opportunity to get our hands dirty :) It is a very straightforward problem and does an excellent job of teaching you the Strategy Pattern. I've pushed my work to Github:

Exercise - Design Puzzle (p.25)
Make sure you have mastered the basics by trying your hand at organising the entity/class diagram in this exercise. Everyone remembers their UML arrows, right? ;)

Exercise - Crossword (p.33)
I know what you are thinking, we are learning and ain't nobody got time for messing around with a crossword! Rather surprisingly however, it is very valuable for seeing if you have been paying attention. Doing it exercises a different part of the brain and in the very least helped me notice I missed a page! Nevertheless it is incredibly frustrating if you're bad at crosswords!


Shared Vocabularly (p.26)
Communicating is one of the greatest challenges facing developers and learning to succintly transfer thoughts from your head to another person's is invaluable. Part of this is using the right language, which in our case is the language of Design Patterns. Learning all of this enables us to communicate faster as well as code faster!

Object Oriented Principles (p.30)

At the very heart of everything we are trying to do, there must be a firm foundation of solid object orientated principles. Design patterns work in tandem with these tenants, you must learn the practice and understand the wisdom behind it. All of this is reassuringly woven into the theme of the book: from subtly highlighting how "Inheritance is evil" to explicit recommendations (program to an interface!)


If you have little to no experience with the Strategy pattern, this chapter is a fantastic way for you to master the art of encapsulating varying behaviour. Even for those with some experience on the topic, the exercises both amuse and tax you, helping to reinforce our knowledge :)

Friday, 31 January 2014

London Code Dojo 30

Monday was London Code Dojo 30 and this time we were back in Barbican with the lovely people at valtech


The kata for the evening was based upon Fibonacci numbers... but with a twist! The problem was centred around Fibonaccimal Numbers (link) which use the Fibonacci numbers as a base for representing numbers. So taking 1, 2,3,5 and 8 as a base, we can represent 9 as 10001 or 01101. As you can see, some numbers can have multiple representations and this added to the complexity of the problem. For the majority of the evening I paired with Rob and I found it really valuable getting his insight into the problem! The code we produced for the night can be found here:


Nothing beats a good plan

More so then anything else, I came to appreciate the value of having a solid plan. Having a high level design which everyone agrees will solve the problem is incredibly important. Test driving code doesn't magically produce well designed algorithms.


Decompose complexity into simple functions

Functional concepts supplement object oriented coding in a fantastically seamless way. When dealing with collections or calculations it is surprising how  higher order functions like map and reduce translate to how you naturally think about the problems.

For instance, to produce all the Fibonaccimal representations of a number, you can use a two step process:
  1. Find all unique ways to express that number as a sum of different Fibonacci numbers 
    • For example: 3 is [3] and [2+1]
  2. Translate each way into the corresponding Fibonaccimal 
    • [3] is 100 and [2+1] is 011
These steps are both mapping a number to a list of lists, then each list to a String. This is reflected in the code below:
return sumsCalculator.fibonacciSumsFor(number) // Step 1
                             .map(toStringCalculator::fibonacciSumToString); // Step 2

Suddenly I've decomposed an abstract problem into two concrete functions which I understand and can test drive!

Perhaps this is the crux behind solving all problems. Reduce the complexity until the solution is series of simple steps. Needless to say, making things simple is not simple... But there in lies the rub :)

Monday, 20 January 2014

Skimmer's Guide - Head First Design Patterns - Introduction

“Our goal was to make the book weigh less than the person reading it... Our focus is on the core patterns that matter...”


I've recently started reading this book along with a few others in the LJC Book Club. As we read the book, I will be producing a series of Skimmer's Guide posts for each significant section of the book. Introduction to Design Patterns, the next section, is here. If you are interested, please join the discussion on our Google+ community


We start our reading of Head First Design Patterns with a gentle and enlightening introduction to the Head First world. Their approach is really intriguing and it is refreshing how much they are vested in helping the reader learn. Everything is to the point and we are immediately told who this book is and isn't for. Our goal in reading this book is stately clearly: learning that design patters are all about reusing experience and creating flexible code.

Despite the daunting size of this book (it is very heavy), the writing style and format makes it very easy and enjoyable to read. If you have experience with Head First books in the past, the introduction could be skipped although I highly recommend giving it a quick skim in the least.


Taster - Table of contents
Surprisingly enough, the novel table of contents work really well as a taster for things to come. Much like the rest of the book, the entertaining writing style brings the book to life :)


Tricking your brain into retaining knowledge
One of the very first concepts covered in the book, this is the art of learning how to best learn. Absolute must read as the techniques covered are applicable to learning in all walks fo life.


Beginning to read this book has been a wonderful foray into the Head First world and has whetted my appetite for more. Looking forward to sinking my teeth into the world of design patterns in the next part :D