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Thank you! This was the most beautiful introduction ever. I was actually crying behind the poster!
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As a professional speaker, I have to set my own timer because I'm a professional. So just an announcement before I start my actual talk.
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I'm very, very humbled to invite you to the official secret after-party. It's going to happen at a place called Canal.
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I didn't have Wi-Fi, so I couldn't translate it to funny characters. But I'm pretty sure you know the place, because it must be an awesome spot.
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It's also a great idea to have the after-party after day one, and then have another day of the conference. It's always great!
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I always love to talk at the last slot, because I'm a little bit hungover, but that's fine!
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So my official conference talk title was 'From OOP to Functional Programming and Beyond'. You can see I'm really talented because I'm using Linux and don’t have Photoshop.
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But I decided to make it even fancier and just call this talk 'Trailblazer' because apparently that's what I'm talking about.
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Actually, I’m not only talking about Trailblazer, functional programming, and object-oriented programming; I’m talking about simplicity.
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Yeah, because it's the last talk of the day and everyone is really tired. Are you ready for the after-party?
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Whoo! That’s how I like it!
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So, um, this is a bunch of my friends and me from two years ago. I can't find myself in the photo, but I’m there. This is about the age when I started to learn about programming.
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I mean, I didn't actually know what I was doing, but I started to get interested in how to operate a computer instead of just playing with it.
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I was one of the first kids in my town to have an Apple Computer Classic. You know, the little box that people now use for fish bowls.
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I had only five games because at that time Apple wasn't cool. I had an Apple before it was cool.
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So I started playing a bunch of computer games, all in black and white. For some reason, I wanted to program a computer game.
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My dad bought me this book, and back in the day, a book like this cost about $200, and it was imported from America.
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I didn’t even really speak proper English, but this was kind of my first programming book. I read 'Tricks of the Trade: Game Programming Gurus'.
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It's pretty awesome, and I still have it somewhere.
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Then I realized that programming actually means you have to learn how to program. The book was written in C++, which is perfect for a 9-year-old kid.
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I started to learn C++ and concepts like variables, and if-then-else statements.
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I remember exactly the day when I learned about functions. I understood that a function is a component I can reuse.
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I got that, but I didn't understand why the arguments A and B were named that way. I thought you had to name them according to what the user of the function wanted.
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Then I kept thinking about it. I was driving with my dad one beautiful November day, and he kept explaining what a function was.
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At some point, it clicked for me. I realized that a function is a piece of logic not affected by anything happening outside of it.
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You push something in, it does some stuff, returns something and nothing else changes. That really intrigued me.
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I had no idea I would be standing on stages talking about components and object-oriented and functional programming.
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But that was the moment when I realized cool programming is a lot about structuring.
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And a function is kind of my best friend. Unfortunately, I made a big mistake and started learning Perl.
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That was my first step into web programming. My friend asked me, 'Are you good with databases?' and I was like 'What?'
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So I started to learn about web programming. Back then, you had to use PHP or Perl.
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After about one or two years, I actually had a website up and running to sell boats and yachts.
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It's not that I owned a lot of boats and yachts, but people would put their advertisements on it. It was like eBay for rich people.
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I wrote it for rich people, but no one used it! That's kind of the story.
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While I was doing Perl, I was still intrigued by the idea of components and having code not affected by other code.
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I didn’t even know what ‘minimizing side effects’ meant at that time.
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I had a really strict object-oriented way of designing my Perl code. Then I made another mistake and started to learn Ruby on Rails.
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Ruby is an amazing language, especially when you come from Perl, because Perl is so ugly, and Ruby looks beautiful.
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Ruby has a dot operator and not some weird arrow, and you actually have objects instead of having to bless some reference.
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In Rails, my first problem was that I didn’t like how you only had three buckets for code: model-view-controller.
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You throw validations, callbacks, and everything into models, and do the same in the controller.
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It’s hard to see where the code is for updating things like a blog post.
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If I ask someone, 'Where is the code for updating a blog post?' they say, 'Um, a little bit in the controller and a bit in my own service object.'
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I was missing structure; I wanted a domain view, with a way to put all the code for updating a blog post in one place.
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Rails is cool and easy to learn, but once it gets more complex, it’s actually not that simple anymore.
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I started to work on a few gems; the sales gem was my first gem.
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Back then, we didn't even have gems; I think it was just a Rails extension or some Rails plug-in.
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What Sales does is help you create reusable widgets in Rails. You can encapsulate that code in the view for a reusable element.
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It’s just like having a class and some code for that widget, and you can call that class with a helper method.
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The cool thing was I could test that in isolation. I could test my partial or my widget in a unit test.
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And that was pretty cool because I love testing. I love when I can test stuff in isolation.
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This connects back to my fascination about functions; it made intuitive sense to me, not only to me but also to others.
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Have you heard of DHH? Here’s an email from 2008 where he said he really liked Sales.
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Of course, nothing evolved from that; DHH and I are still friends.
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DHH is the guy who is famous for his emphasis on pushing everything into one class, calling it amazing.
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He claims you can make millions by doing it—that's what they do in Basecamp.
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Another gem I worked on is the Reform gem. It’s a gem that only sorts out validations with form objects.
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If you have a form on your website, you define the fields and validations in that form's class.
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Instead of pushing validations into the model and controller, you have all the validations in one class.
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The cool thing about this is that you can test it; you can call that validation in isolation without the entire application complexity.
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You just need to call the function, and it will give you a result object.
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What I found was that while using those gems, I still felt lost at times in Rails codebases.
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At the same time, Rails was telling people to push all code into one class, which can lead to complexity.
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The more you separate components in your code, the simpler it gets. It isn’t simple to have one class with a million responsibilities.
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This is when I started to think about an alternative framework, and I began working on Trailblazer.
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The key insight of Trailblazer is that it does not replace Rails; we are not trying to make all the cool things of Rails null and void.
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We’re extending the framework. If anyone has a good inspirational quote, please tell me.
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In the first version of Trailblazer, we had very simple controllers that only did HTTP-specific stuff and rendering.
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We called what we called an operation, and the operation took over the orchestration of the business code.
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So controllers are very simple, and the models only handle what ActiveRecord does well: querying and writing to the database.
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We can discuss if the writing part in ActiveRecord is good or not, but it's great for SQL abstraction.
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But it’s not great for callbacks, validations, or domain code.
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In Trailblazer, the goal is to have an ActiveRecord class that only does SQL abstraction.
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Models are cleaned up; instead, we introduced a new structure called operations.
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Every operation has only one responsibility: creating a comment, deleting a user, or archiving a blog post.
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Many people were concerned that we were just creating another god object, and the operation would do all the code.
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But the operation does not implement everything in one big chunk of code; instead, it orchestrates different stakeholders.
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We connect with form objects, ActiveRecord, SQL, ROM, or whatever you want.
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The operation acts as an orchestrator, not an implementation; it’s very beautiful.
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Here's a version one example: the operation is a class. You see the name 'comment create'; it’s going to create a comment.
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People were scared about creating new classes in Ruby; they thought it was going to be slow.
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But this is object-oriented programming; if you need to solve something, you solve it in a separate class.
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Ruby’s garbage collection is designed for small objects that die quickly, not for huge monolithic objects.
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The funny thing was that the Trailblazer way actually sped up applications.
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The idea of this operation is to have one public method, and you call that operation.
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It runs whatever it does and returns you a result object with no other public methods.
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It's like a function in functional programming; it allows you to avoid messing up system state.
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The version one result object tells you whether it was successful or not.
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You ask the operation instance if there was a mistake, and the cool thing is you can test it.
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You can call that operation in a unit test, and it behaves the same in a controller.
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It’s amazing, and it’s hard in Rails to replicate that without an integration test.
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The idea was to take code into a separate class and make it testable, which I really liked.
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Another amazing aspect of the operation was that you could use it as a factory.
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Instead of using FactoryBot or whatever you use for fixtures, you would use the operation.
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You could chain operations to set up application state, making everything simplier.
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You’d have the exact application state you needed for testing.
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By making things explicit, it actually got simpler. Then I had a great idea.
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I started writing a book about the framework while working on it. It was horrible because as I changed the API, I also had to change the book.
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The book was called 'Trailblazer: A New Architecture for Rails'—you don't have to buy it.
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If you buy it, I will have more money to buy Rakia tonight, which is great!
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People were mad because they thought the project must be finished because there's a book.
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It didn’t solve all their problems; surprise, open source! They got really mad at me.
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They thought, 'This book is going to solve all your problems automatically.' It wasn’t perfect.
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But that was a crazy experience—writing while simultaneously developing a framework.
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The main idea for Trailblazer was to have an operation reflecting a verb of your domain: creating, deleting, or archiving.
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Initially, the operation had one method called process, where you’d do all the code.
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That was a mistake because people wanted to customize what happens.
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They would have to know the call stack, which was really stupid.
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No one wants to learn the internals of a call stack and understand the method calling order.
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Came from C++ and Perl, where everything is about objects and call stacks.
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But it turned out to be the wrong design for an orchestration class.
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The principle of having methods calling methods with super became complicated.
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I found out this wasn’t a good architecture.
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Ruby has great objects, but the way modules work may have issues.
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So I started to consider moving into functional programming.
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I learned that functional programming is simple: you pass input, you get output back with no side effects.
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The cool thing is that nothing else changes beyond that.
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Looking at the operation, we were already doing what a function does.
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I didn’t recognize it as such until I learned more about functional programming.
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It became apparent that operations are functions in their own right.
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However, we still had this problematic call stack. I knew we had to simplify that.
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In the next version of Trailblazer, we introduced a DSL to define steps.
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This DSL allows you to declare what you want your business code to do.
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Each operation builds a graph of steps in the background, allowing for conditional operations.
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This was inspired by railway-oriented programming.
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The idea is that this pattern allows the flow of control to be managed without difficult programming.
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Via the DSL, operations can create a structured path for workflows that either work or skip certain steps.
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I created an animation demonstrating this concept, and I hope to get some appreciation!
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It simplifies the session’s workflow and allows programming through clear steps.
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Using a DSL and visualized graphs allows us to represent operations in a much clearer way.
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Users found it exciting to see steps in graphs instead of all the if-else structures.
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The operation transforms the complex into something simple and visually clear.
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Everyone liked using functions in a way that didn’t get convoluted with too many steps.
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And still, they began to request more features after getting used to this.
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It’s always after you make something easier that people want even more.
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They suggested tracing features so they could visualize workflow paths.
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Tracing is important because it shows the path an operation takes through different steps.
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The challenge was I had to change a lot for this to work.
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In version 2.0, we shifted from the process method to the DSL.
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People didn’t like that we broke the API; they preferred to stick with the old way.
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Working on open source often becomes a psychology experiment, because people resist change.
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When you innovate, people push back, but later they often appreciate what you did.
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In the new version, we included tracing so they could visualize inputs and outputs.
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This feature helps to understand what is happening at every state, making operations better.
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So we gave them longer-running workflows which could handle millions of requests.
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Using the workflow engine, we gain control over what happens in our code.
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We provided a visual editor to allow users to model their workflows better.
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It allows you to link operations visually without having to rely on complex code.
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Peter Wagner’s business process modeling notation (BPMN) aligns with what we did.
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This is useful because the police department had numerous processes they needed to visualize.
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They had tons of documents full of diagrams which didn’t correlate with the code.
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By using BPMN, we can automatically generate required documentation from the code.
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This process will cut down refresh cycles for these confusing documents.
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Finally, models can create these diagrams, making everything run smoother.
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Now we're seeing a shift towards a simpler, more visual programming style where we focus on smaller components.
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You only work on the implementation while the control flow is handled by the framework.
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As we wrap up this session, I encourage you to explore these new approaches within the Ruby community.
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With all the new gems, Ruby can greatly benefit from the innovation surrounding functional programming.
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Embrace simplicity, create components and abstractions instead of stuffing everything into one class.
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Thank you for listening! Don’t forget to come to the after-party at Canal!
