July 09, 2025 · 476 words · 3 minutes reading time

Convention over Configuration: A Senior Architect’s Perspective on Modern Software Design🔗

1. Why We Need CoC: The Pain of Early Configuration-Driven Systems🔗

In the early Java EE days, enterprise developers spent countless hours writing XML just to describe what the application should already know...

• Over-declaration: every bean, service, and controller had to be manually wired.
• Separation of concerns gone wrong: configuration scattered outside implementation.
• Cognitive overhead: understanding the system meant parsing endless files.

If 90% of projects follow a similar structure, why not standardize it?

This is the exact problem CoC solves.

2. What Is Convention over Configuration?🔗

“Don’t write configuration for things the framework can figure out.” — DHH, creator of Ruby on Rails

The idea is simple:

• Prefer sensible defaults over explicit setup.
• Encourage implicit structure through file naming and organization.
• Let developers focus on what’s different, not on repeating boilerplate.

3. CoC Across Languages and Frameworks🔗

Framework	CoC in Action	Tooling
Rails	Folder-based MVC, no route config	rails generate scaffold
Spring Boot	Autowiring, annotations over XML	@ComponentScan etc.
Django	App naming, admin auto discovery	startapp, urls.py
Laravel	Controller + Resource Route bindings	artisan make:controller
NestJS	Module structure + Decorator syntax	@Controller, @Module()

These frameworks adopt the same mental model — directory structure, naming rules, default lifecycles.

4. CoC as an Engineering Doctrine🔗

CoC is not just a DX (Developer Experience) trick — it’s an engineering design strategy.

Good architecture is invisible.
It guides teams without needing to be constantly enforced. CoC helps in:

• Code consistency across teams
• Reduced onboarding time
• Minimized error surface
• Automated tooling compatibility

5. Architecture Visualization🔗

This diagram illustrates how modern frameworks integrate:

• Scaffolding
• Default behaviors
• Naming conventions
• Directory layout

...into a unified, opinionated software system.

6. CoC in DevOps and Microservices🔗

Convention-driven tools like:

• Terraform: Directory layout & variable naming
• Kubernetes YAML: Label selectors, config maps
• CI/CD: .github/workflows/, Jenkinsfile, etc.

All rely on shared conventions. As environments scale, conventions become guardrails.

7. Code Portability Enabled by CoC🔗

Once you understand Rails, you’ll pick up Laravel or NestJS quickly — because CoC abstracts language differences.

// NestJS
@Controller('posts')
export class PostController {
  @Get(':id')
  async show(@Param('id') id: string) {
    return this.postService.findOne(id);
  }
}

// Laravel
public function show($id) {
  $post = Post::find($id);
  return view('posts.show', compact('post'));
}

# Rails
def show
  @post = Post.find(params[:id])
end

8. AI, Automation & Future of CoC🔗

Even modern AI workflows adopt CoC:

• data/, model/, train.py, inference.py — this is a de facto convention
• MLflow and Kubeflow pipelines follow predictable directory and module conventions
• Prompt-based coding (Copilot / GPT) relies heavily on knowing the structure

This shows CoC is not obsolete — it is evolving.

9. Final Thoughts🔗

CoC is not a limitation — it’s a productivity enabler.

• It minimizes choices that don’t matter.
• It promotes clarity, collaboration, and growth.
• It enables rapid transfer of skills across ecosystems.

"Conventions are a gift to your future team."

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Written by a Senior Software Architect & Platform Engineer