Book Recommendations from Sydney Technology Leaders

Last week I went to the Sydney Technology Leaders’ Meetup, which we hosted in the Tyro Fintech Hub. There was a trio of great talks, and a panel discussion with the speakers at the end.

When asked what they do to help train new leaders, one of the speakers mentioned “throwing a bunch of books at them”. So I took the opportunity to ask the speakers, if they could only recommend one or two books to a new leader, what would each of them recommend. Continue reading

Design Kata: Learn software architecture while having fun

Children practising a karate kata. This article describes design kata, where software developers practise designing software architecture.At Tyro, we don’t have anyone with the title of Architect, Designer or Tech Lead who designs software and then asks other people to build it. Instead, each team of Software Engineers does architecture and design as part of their iteration planning sessions for the stories we’re taking on.

As a Team Lead, the two main goals I keep in mind for each person are: keep them happy and keep them growing. One of the ways I try to ensure this happens is by meeting with each person regularly so we can chat about how to make sure these things are true or at least heading in the right direction.

A topic that’s come up with a few people lately is software design and architecture. Specifically, I’ve had a couple of comments along the lines of: “When we’re designing things, I want to contribute more, but I’m not really sure where to start.” Continue reading

Microservices Security: All The Questions You Should Be Asking

I spoke earlier in the year at the Sydney Microservices Meetup about the long path we’ve taken at Tyro Payments over the last decade, gradually tending towards a more fine-grained SOA approach – microservices as it’s come to be known recently.

Hacker-looking character sitting at a Mac in a dark room, checking out your microservices securityI covered a lot of ground in that talk, but something I didn’t get around to talking about was security. However, I believe that’s a really important topic to think about in microservice environments. It’s even more important than with a monolith, because in a service-oriented architecture you’re making a lot more of your system’s functionality directly exposed to the network, and that puts it in closer reach of would-be attackers, or “increases the attack surface” as a security pro would say.

So last week I presented another talk entitled “Microservices Security: All the Questions You Should Be Asking”.

Microservices Security: Let’s Share What We Know!

I want to tell people all about what we’ve been doing about security at Tyro lately. Security is incredibly important to the IT community and I think it’s imperative that we help each other improve. I want to share with the world some of the problems we’ve dealt with and some of the great solutions our team has built. Continue reading

Alan Turing: The Enigma by Andrew Hodges (Book Review)

Alan Turing: The EnigmaAlan Turing: The Enigma: The Book That Inspired the Film “The Imitation Game”
by Andrew Hodges

My rating: 3 of 5 stars

If I had to describe this book in one word, it would be: “indulgent”.

The author has obviously spent a lot of time researching many facets of Alan Turing’s life and work. (It seems he even interviewed many people who knew him.) However, he doesn’t appear to have spent much time deciding what not to put in the book. Consequently, it’s very long, and by a third of the way through it, when I was still reading about Turing’s uncomfortable years at boarding school, I seriously considered giving it up.

I didn’t give up, though, and I was glad in the end.

The middle sections of the book, explaining first Alan’s pioneering work as a young mathemetician, then his contribution to cracking the Enigma system, and then his diversion into the design and operation of early computers, were a really interesting read. The author went into quite a lot of mathematical and technical detail in parts which, as a software engineer, I quite enjoyed.

It was very interesting for me to realise that his major achievement was really in his mathematical endeavours rather than in computing. He didn’t do a whole bunch of amazing hardware stuff alone, unlike the film tried to suggest, and the team that eventually built the first working general purpose computer did it in competition with the group Turing was working with, though that project’s lack of progress was not of his making. However, his contribution to mathematics, by proving that there were uncomputable problems, was extremely significant at the time, and Hodges does a good job of setting the scene and describing how Turing’s discovery came about.

During the narrative of these later parts of his life, many of the episodes and observations from Turing’s early life are linked into the story, showing how his upbringing contributed to, and sometimes adversely affected, his pursuits. However, the same links could probably have been drawn with far less detail spent documenting his childhood.

The documentation about his eventual demise leads into some nice, reflective wrapping up about his whole life. This too, though, is probably more long-winded than it needed to be.

All in all, I learnt a lot about the man, about his achievements, about the war, and a few things about maths and computing. I would have preferred it to be a whole lot shorter, though.

PS – I read this book because the movie had come out and I wanted to read the book first. The movie is so far from what is documented as reality in this book that having read the real story actually ruined the movie for me. If you want to both watch and aread, I suggest you watch the movie first, understanding it strays very far from the truth, then read the book afterwards to get the true story.

Alan Turing: The EnigmaBuy it on Amazon

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Notes from YOW! 2014: Simon Brown on ‘Agility and the Essence of Software Architecture’

I attended YOW! Sydney 2014 and thought some people might get something useful out of my notes. These aren’t my complete reinterpretations of every slide, but just things I jotted down that I thought were interesting enough to remember or look into further.

Simon Brown (@simonbrown) spoke on “Agility and the essence of software architecture”. (Slides, Video)

He started with a great Dave Thomas quote:

“Big design up front is dumb.
No design up from is even dumber.”

Whiteboard covered in a circuit diagram, which looks pretty similar to a typical software architectureSoftware Architecture Agility

He went on to tell us…

Delivering software in an agile way doesn’t guarantee that you’ll develop an agile architecture.

A good architecture enables agility.

He asked “Are monolithic architectures agile?” and proposed the answer, “Well, they could be. Just because you have to deploy it all at once doesn’t mean it’s not agile.”

Which naturally lead into a discussion of what does agility mean? Continue reading

Notes from YOW! 2014: From Monoliths to Microservices at REA

I attended YOW! Sydney 2014 and thought some people might get something useful out of my notes. These aren’t my complete reinterpretations of every slide, but just things I jotted down that I thought were interesting enough to remember or look into further.

Microservices at REA (Real Estate Australia)Beth Skurrie (@bethesque) from DiUS, Evan Bottcher (@evanbottcher) from Thoughtworks and Jon Eaves (@joneaves) from REA group spoke about migrating realestate.com.au to a microservices architecture. (Slides, Video)

Why REA migrated to microservices

They started by talking about why they started doing microservices:

  • They had a long release cycle,
  • they were doing coupled releases,
  • with coupled rollbacks,
  • and they had a long defect fix time.

How do you get self-empowered teams to change the whole architecture?

However, there was a realisation that changing things at REA is a bit hard, partly because the teams are very self-empowered, they’re trusted, and they value their independence.

In order to convince teams that trying a new architecture was a good idea, they came up with a vision of where they wanted to go, which included: Continue reading

How to Avoid Making Huge Mistakes with Life’s Big Decisions

The Mistake

A condemned three-story house in DetroitWhen my wife and I had been married for a year, we made a decision to purchase an apartment. It remains, to date, the worst decision we’ve ever made.

To start off with, we probably shouldn’t have purchased anything at all. But there was pressure from parents, the peer pressure of our friends doing the same thing, and the constant fear in Sydney-siders of “getting left behind the market”. Looking back now, I see the bigger factors that we’d been married for one year, we were both very early in our careers, we had very little savings relative to our incomes, and we were living in a friend’s place for low rent. There weren’t really any good reasons to buy.

The big mistake, though, was the place we bought. Continue reading

Notes from YOW! 2014: Troy Hunt on Security: ‘Hack Yourself First’

I attended YOW! Sydney 2014 and thought some people might get something useful out of my notes. These aren’t my complete reinterpretations of every slide, but just things I jotted down that I thought were interesting enough to remember or look into further.

Troy Hunt (@troyhunt) spoke about “developers building up cyber-offence skills and proactively seeking out security vulnerabilities in their own websites before an attacker does”. (Slides, Video)

Hackers Are Security Experts

A stereotypical security hacker, using a computer in a dark room while wearing a guy flakes mask and a black hat.He started out with the obvious but perhaps too often forgotten observation: “You can’t defend your app unless you actually understand how the hacker’s technology works.”

He described how hackers only need to “get it right” once. Those developing and deploying the system need to get it right every time. (This is sometimes called the “Fortification Principle”. Apparently DARPA are working on evening out the playing field.)

Know Where Security Applies

He asked: If your company has a Twitter account, who chose the password? The marketing intern, or the Security team? Continue reading

Notes from YOW! 2014: Ed Kmett on ’Stop Treading Water: Learning to Learn’

I attended YOW! Sydney 2014 and thought some people might get something useful out of my notes. These aren’t my complete reinterpretations of every slide, but just things I jotted down that I thought were interesting enough to remember or look into further.

Ed Kmett (@kmett) started by asking: “What is the cost of using the wrong solutions, integrated over your entire career?” (Slides, Video)

Then he revealed that the topic he’d chosen for the talk was…

“How to be a genius”.

Portrait of genius physicist Richard FeynmanHe talked about a strategy for solving big problems described by famous theoretical physicist Richard Feynman (pictured):

  1. Keep a bunch of your favourite problems in your head.
  2. Every time you hear a new idea -> test it against one of your problems to see if it helps.
  3. If it does, tell people about the breakthrough, and they’ll think you’re a genius.

Note that, in Feynman’s approach, genius is attributed not necessarily to those that come up with new ideas, but often to those who figure out where to apply them.

Developers and Researchers

He noted that developers are in the business of solving problems, searching for solutions, while researchers often have solutions, but are searching for the right problems to apply them to. As a developer, it can be good to keep abreast of what researchers are discovering in hope of finding a solution to one of your favourite problems.

Memory Retention

He discussed human memory retention and the need to revisit topics over time to retain knowledge about them. The brain remembers far better information that is used or revised repeatedly. Knowing this, you can hack the brain by intentionally repeating material that you want to remember. (For example, after going to a conference, you could write a blog about the important points from each talk you went to.)

He chatted a little bit about jargon, saying that if you’re going to use jargon, you should always be willing to explain what it means.

Image credit: Richard Phillips Feynman (1918 – 1988) (unknown)

(My notes from) Ken Scambler on ‘Two Years of Real-World FP at REA’

This evening I went to a YOW Night where Ken Scambler (@KenScambler) spoke about the introduction and evolution of using Scala at REA Group. Here’s my notes…

Functional Scala Benefits

The sprial logo of the functional programming language language ScalaThe benefits of going functional are to get to code that is: Modular, Abstract, Composable.

Modularity is about being able to fit entire sections of code in your head without having to consider things going on outside that code, and also about being able to replace small parts without affecting the whole.

To write a total function (a function that returns a result for all possible input values), you need to elevate all possibilities into the type system. For example, you can’t throw an exception, you have to encode that possibility of an error into the return value somehow.

Abstraction should reduce changes to code, because unnecessary detail is not all across the code.

Whole systems can be composed from functional components.

Functional programming is not about picking up a hipster language. It’s about producing better software.
Continue reading