Engineering - Schembri on Software

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23 May 2025 • 7 min read

SOLID: Dependency Inversion Principle (DIP)

The dependency inversion principle is about inverting dependencies. Right? Actually, maybe not.

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17 May 2025 • 5 min read

SOLID: Interface Segregation Principle (ISP)

The Interface Segregation Principle is about designing thin, cruft-free interfaces which results in reduced coupling.

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10 May 2025 • 5 min read

SOLID: Liskov Substitution Principle (LSP)

The Liskov Substitution Principle applies to any OOP language. On the surface it is a structural principle, but its true lesson is concerned with behaviour.

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1 May 2025 • 7 min read

SOLID: The Open–Closed Principle (OCP)

We visit the second SOLID principle: the open–closed principle (OCP). Does it still hold up, or is it bad advice in today's agile world?

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19 Apr 2025 • 5 min read

SOLID: The Single-Responsibility Principle (SRP)

The Single Responsibility Principle is harder to grasp than its name implies, with a history of misleading definitions. We're going to be pedantic about the definition right out of the gate, to ensure we come away with the right understanding.

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19 Apr 2025 • 4 min read

SOLID for Ruby Engineers

The SOLID principles are required learning for software engineers dealing with object-oriented code. Think you know them? Let's take each one apart together.

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6 Apr 2025 • 5 min read

Your Dependencies Are Not Free

Dependencies are free chunks of functionality, except when they're not. They come with hidden costs which need careful consideration.

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21 Dec 2024 • 8 min read

Complexity

I dislike [all] blanket statements, but complexity is never desirable. Managing complexity is the most important technical topic in software development. In my view, it’s so important that Software’s Primary Technical Imperative has to be managing complexity. — Steve McConnell, 2004 It must have been around 2008 that I

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14 Jul 2023 • 2 min read

My App is Slow. Who Cares?

It's not a rhetorical question. Who, and why, do people care if your app is slow? What is the purpose of the code you're writing? Whom does it impact? And where is the author going with this? Today I came across a post on social media

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A coffee splash erupting from a cup, forming an artistic arc with droplets in mid-air. The focus is on the motion and energy, with a blurred background suggesting an outdoor setting.

14 Aug 2022 • 3 min read

Debugging Software and Coffee

Our coffee machine is currently at the shop for repair, so we're stuck drinking instant. It's not fantastic, but it's really all right in a pinch. In fact, my parents exclusively drink instant because it's what they're used to — seems

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