Clean Architecture in Frontend: Lessons from Building Scalable React Applications

Working at I-care, we maintain frontend applications used by some of the largest industrial companies in the world. As features piled up, we found ourselves drowning in tightly coupled components — and the fix didn’t come from a new framework.

Clean Architecture, popularized by Robert C. Martin, is usually discussed in the context of backend systems. But its core principles — dependency inversion, separation of concerns, and protecting business rules from delivery details — translate beautifully to frontend codebases.

The four layers we settled on

We organized the project around four concentric layers. Dependencies always point inward.

export class Profile {
  private constructor(private props: ProfileProps) {}

  public static create(data: ProfileData): Profile {
    if (!data.name) throw new Error('Profile.name cannot be empty');
    return new Profile({ ...data });
  }
}

The domain layer has zero framework dependencies. No React, no Astro, no fetch. Just plain TypeScript that models business rules.

The first time you delete a UI library and your domain tests still pass, you know you’ve drawn the line in the right place.

What changed in practice

• Repositories became the only way data crossed into the domain.
• Use cases became the only way the UI could ask the domain to do something.
• Tests ran in milliseconds because the domain didn’t need to mount a component tree.

It took us roughly a quarter to retrofit the existing codebase. The payoff: onboarding time for new engineers dropped from weeks to days.