One Size Does Not Fit All

This talk examines how to choose the right size for software components, from classes and functions to microservices. It uses examples and antipatterns to explain information hiding, separation of concerns, and cohesion.

Syllabus

Introduction
Commonalities
Just make things the right size
Information Hiding
Separation of concerns
Single Responsibility Principle
Cohesion in 00: Object Calisthenics
Indicators of strong cohesion
Indicators of weak cohesion
Forces for separation
Environments
Microservices - Common Traits
Example: Pricing Engine
Super-small, really micro, nano
Example: Product Detail Page
Small, micro
Example: E-Commerce Site
Medium-sized
Hierarchy & Rule Example
Antipattern: Decoupling Illusion
Antipattern: Anemic Service
Antipattern: Unjustified Re-Use
What works