Designing With Concepts

“Designing good software isn’t just about writing good code. It’s about thinking clearly about what the code represents.”

Every software product — from the smallest mobile app to the largest distributed platform — is built out of concepts.

These concepts are the invisible architecture of your system. They are not UI elements or function names. They are the core units of meaning that define what your system is, what it does, and how it evolves.

🌱 What Is a Concept?

A concept is a coherent unit of meaning and behavior in a system.

In a note-taking app, a “Note” is a concept.
In a banking system, a “Transaction” is a concept.
In a social media app, a “Post” is a concept.

A well-formed concept can be reasoned about independently, even though it works in concert with others. It should answer questions like:

What does this concept represent?
What are its core responsibilities?
How does it evolve over time?
How do other concepts interact with it? Designing software around first-class concepts is a recipe for clarity, composability, and longevity.

🔁 Case Study 1: The Concept of Backup

Let’s begin with a deceptively simple example: Backup. Almost every system includes it, yet implementations differ widely.

🔍 What Is Backup, Conceptually?
Backup means capturing the state of data such that it can be restored later in case of loss, corruption, or failure.

This definition is independent of:

What is being backed up (files, DB, user data),
How it is stored (cloud, tape, drive),
When it runs (manual, scheduled, real-time).
What matters is the behavioral contract: capture → preserve → restore.

🔸 Backup in Databases (e.g., MySQL)

Granularity: Tables, rows, transactions.
Mechanism: mysqldump, xtrabackup, binlogs.
Restore Path: Requires schema, data, and logs.
Design Invariant: Backup must be transactionally consistent, versioned, and recoverable.

☁️ Backup in Backblaze

Granularity: Files and folders.
Mechanism: Agent watches file system and uploads diffs.
Restore Path: User browses versioned cloud archive.
Design Invariant: Continuous, file-level snapshots with user-accessible history.

📁 Dropbox: Sync and Implicit Backup

Granularity: File + version history.
Mechanism: Real-time diff sync.
Restore Path: Rollback to any previous version.
Design Invariant: Consistent, device-agnostic backup via versioned file history.

✅ All three fulfil the Backup concept’s essential contract:

Maintain a restorable snapshot of state, decoupled from the active system.

🧵 The Concept of Post

A Post is a universal concept in content-driven systems: user-generated content published with metadata, time, and visibility constraints.

🐦 Twitter: The Tweet

280 characters
No edit (until recently)
Public and viral

👥 Facebook: The Status Update

Longer text
Multimedia-rich
Audience-scoped (friends, groups)

✍️ Medium: The Blog Post

Rich text, formatting, links
SEO-relevant metadata
Editing, publishing workflow

✅ All of these are Posts. They differ in medium and mechanics, but they share the core concept:

A user creates and shares content, tied to time, identity, and visibility.

💡 Why This Matters

Designing around core concepts has several benefits:

Clarity: Each concept is independently understandable.
Composability: Concepts can be combined and reused.
Change-resilience: You can evolve one concept without de-stabilizing others.
Cross-platform thinking: Recognizing common concepts across domains helps in abstraction and reuse.

🧭 Principles for Designing with Concepts

Name the concept — don’t let implementation details distract you.
Define its responsibilities — what it owns and does.
Map variations across systems — how the concept morphs.

🎯 Conclusion: Think in Concepts, Not Code

Concepts are the true atoms of software design. They transcend syntax, frameworks, and even domains. Whether you’re dealing with backups in a database or posts in a social app, recognizing the underlying concept gives you clarity and leverage.

But the deeper benefit is this:

Thinking in concepts helps you build an internal design catalog — a mental library of behaviors, constraints, and patterns that you can draw on across projects, teams, and technologies.

With time, you’ll stop designing from scratch. Instead, you’ll reach for concepts you already know — like “Post”, “Backup”, “Tag”, “Identity”, or “Membership” — and adapt them with precision and elegance.
Designers who think this way don’t just write clean code — they create coherent systems.

Think in concepts. Build your catalog. That’s how great designers are made.