Traditional event-based MVC has been the standard pattern for building user interfaces for decades. However, this pattern has its downsides – specifically, shared mutable state and cascading event chains can lead to code that is difficult to comprehend and reason about.

In this talk we’ll look at alternative approaches that leverage functional programming techniques, using the native mobile app development space to demonstrate. We’ll start by introducing the concepts of declarative UIs and reactive one-way data flow, as exemplified by the JavaScript-based React Native framework. Then, if JavaScript is not your cup of tea, we’ll see how we can apply the same principles using Swift and ReactiveCocoa, a functional reactive programming library for Cocoa.

Irrespective of what language you use or what sort of user interfaces you build, this talk will introduce you to the virtues of reactive one-way data flow and immutable state, and how they can help you write code that is easier to understand.

Traditional event-based MVC has been the standard pattern for building user interfaces for decades. However, this pattern has its downsides – specifically, shared mutable state and cascading event chains can lead to code that is difficult to comprehend and reason about.

In this talk we’ll look at alternative approaches that leverage functional programming techniques, using the native mobile app development space to demonstrate. We’ll start by introducing the concepts of declarative UIs and reactive one-way data flow, as exemplified by the JavaScript-based React Native framework. Then, if JavaScript is not your cup of tea, we’ll see how we can apply the same principles using Swift and ReactiveCocoa, a functional reactive programming library for Cocoa.

Irrespective of what language you use or what sort of user interfaces you build, this talk will introduce you to the virtues of reactive one-way data flow and immutable state, and how they can help you write code that is easier to understand.

Traditional event-based MVC has been the standard pattern for building user interfaces for decades. However, this pattern has its downsides – specifically, shared mutable state and cascading event chains can lead to code that is difficult to comprehend and reason about.

In this talk we’ll look at alternative approaches that leverage functional programming techniques, using the native mobile app development space to demonstrate. We’ll start by introducing the concepts of declarative UIs and reactive one-way data flow, as exemplified by the JavaScript-based React Native framework. Then, if JavaScript is not your cup of tea, we’ll see how we can apply the same principles using Swift and ReactiveCocoa, a functional reactive programming library for Cocoa.

Irrespective of what language you use or what sort of user interfaces you build, this talk will introduce you to the virtues of reactive one-way data flow and immutable state, and how they can help you write code that is easier to understand.

Elm, for a long time the flag bearer of Functional Reactive Programming on the web, recently switched to a simpler pure functional architecture, citing 'ease of use'. Those of us that have worked on complex reactive mobile apps can sympathise with this - using FRP injudiciously in your app can make the code difficult to understand and near impossible for new developers to pick up.

So are we able to apply some of the techniques and patterns from Elm into iOS apps? It turns out the Elm architecture is a really great fit for Swift & iOS - it allows us to:

• reserve our FRP hammer for the use cases that make the most sense
• separate out a simple, consistent, and highly testable pure functional core, and
• provide a flexible, yet easily understood & applied set of architectural building blocks.

This session will cover the basics of implementing and using an Elm-style architecture in a Swift app, will include lessons learnt in a real-world implementation, pitfalls/benefits, and implementation considerations should you adopt the approach in your own app.

Many developers harbour the dream of throwing off the shackles of corporate serfdom and experiencing the glorious freedom of self-employment. So is the grass really greener on the other side? As a developer who took the plunge a few years ago, I can offer some honest feedback and practical advice on things like:

• what to consider when assessing whether self-employment is right for you.
• the different software development business models, the pros & cons of each.
• setting up a business/company - which structure is best.
• knowing when to quit your job.
• pricing yourself correctly.
• sales & marketing - critical activity or soul destroying waste of effort?
• why on earth can’t people just pay you on time.
• what to say to friends and relatives who think you don’t do anything all day.

And generally everything else that I know now, that I wish I knew then.

Elm, for a long time the flag bearer of Functional Reactive Programming on the web, recently switched to a simpler pure functional architecture, citing 'ease of use'. Those of us that have worked on complex RxSwift/ReactiveCocoa apps can sympathise with this - using FRP injudiciously in your app can make the code difficult to understand and near impossible for new developers to pick up.

So are we able to apply some of the techniques and patterns from Elm into Swift iOS apps? It turns out the Elm architecture is a really great fit for Swift - it allows us to:

• reserve our FRP hammer for the use cases that make the most sense
• separate out a simple, consistent, and highly testable pure functional core, and
• provide a flexible, yet easily understood & applied set of architectural building blocks.

This session will cover the basics of implementing and using an Elm-style architecture in a Swift app, will include lessons learnt in a real-world implementation, pitfalls/benefits, and implementation considerations should you adopt the approach in your own app.