architecture

Service objects extract complex business logic from models and controllers, following Single Responsibility Principle. I structure services with a clear public interface—typically a call method. Services handle multi-step operations, external API call

React favors composition over inheritance for code reuse. Instead of extending component classes, I compose smaller components into larger ones. Higher-order components (HOCs) wrap components to add behavior, while render props pass rendering logic as

Outlets allow Stimulus controllers to reference and communicate with other controller instances, enabling composition without tight coupling. I define outlets by specifying which controller types to connect to, and Stimulus automatically finds matchin

Multi-tenancy allows multiple clients to share one application with isolated data. I use django-tenant-schemas for PostgreSQL schema-based isolation. Each tenant gets a separate schema (database namespace). The middleware routes requests to correct te

MVVM (Model-View-ViewModel) separates concerns cleanly in iOS apps. Models hold data, Views display UI, and ViewModels mediate between them with business logic and state. Views bind to ViewModel properties using Combine or SwiftUI's property wrappers.

As business logic grows, controllers become bloated with transaction management, error handling, and cross-model orchestration. Service objects extract this complexity into dedicated classes with a single public method (usually call), keeping controll

Command objects (a.k.a. “actions”) make controllers boring. They’re easy to test, easy to instrument, and they produce a stable API for the rest of your app. This is the kind of structure that makes large Rails apps maintainable.

The Coordinator pattern separates navigation logic from view controllers, promoting reusability and testability. Coordinators own navigation controllers and decide which screens to show based on user actions. Each flow (onboarding, main, settings) has

Callback chains become spooky action at a distance. A simple in-app event bus keeps side effects explicit and testable. This isn’t about Kafka—it’s about clarity and seams.

MVVM separates concerns in Android apps—Model holds data, View displays UI, ViewModel mediates with business logic. ViewModels survive configuration changes, preventing data loss during rotation. I use ViewModel class with viewModelScope for coroutine

ViewComponents bring object-oriented design to Rails views, making complex UI elements testable and reusable. Each component is a Ruby class paired with a template, encapsulating both logic and presentation. I use components for buttons, cards, modals

Service objects encapsulate complex business logic that doesn't belong in models or controllers. Each service performs one operation, like creating a post with side effects, processing a payment, or importing data. I create services in app/services wi