It has been said that immutability changes everything. But what does that mean in practice? What does it mean for existing code that looks more like the mutant apocalypse than an elegant application of mathematical thinking?

Immutability can be an ideal that is hard to reach. Refactoring, on the other hand, is all about the art of the possible. In this hands-on workshop, we'll be looking at some tricks and tips to help reduce the mutability of code.

So bring a laptop, but don't worry about IDEs, editors, compilers and all that — just browser and WiFi! We'll be running the hands-on part using cyber-dojo.org, working with unit tests, promiscuous pairing and good humour :-)

"We're looking for passionate programmers!" says the job ad. For a love-in or a development role? Passion is used to evoke single-mindedness, drive and intensity, but it also has many other meanings, surely not all of which can be intended. Love aside, passion also spills over into irrationality, aggression — e.g., crimes of passion — and unconditional and unquestioning pursuit of ideas. Our acceptance of this word and this quality should be partial and conditional. But there is more than one kind of passion, and when raw passion is tempered with compassion and dispassion we start to see a more balanced way of development.

Good development draws on both creativity and rationality, on both experience and experimentation, on both focus and connection, on both individual skill and group intelligence. The dry language of productivity needs to admit the possibility of enjoyment; the culture of burn-out needs to give way to humanity and empathy. Let's explore the many passions of programming.

It has been said that immutability changes everything. But what does that mean in practice? What does it mean for existing code that looks more like the mutant apocalypse than an elegant application of mathematical thinking? Immutability can be an ideal that is hard to reach. Refactoring, on the other hand, is all about the art of the possible. In this talk we'll be clarifying motivation and exploring some approaches to help reducing state mutability in code.