Defining the Roles Honestly

The terms “React developer” and “full stack developer” are used inconsistently enough that the first step is defining them clearly for your context:

• React specialist: Deep expertise in React, TypeScript, state management (Redux/Zustand/Jotai), performance optimisation, Next.js, and the full frontend surface area. Can build a complete frontend independently. May have basic backend knowledge but is not the person you want writing production APIs or database schemas.
• Full stack developer: Can build both the frontend (React, typically) and the backend (Node/Express, Django, Rails, etc.) and has working knowledge of databases and deployment. The depth at each layer is usually less than a specialist — but for many products, the breadth is more valuable than the depth.

The Cost Difference

Full stack developers typically command a 10–15% premium over React specialists at the same experience level. This reflects their broader scope — but the premium can be misleading if you hire full stack and primarily use the frontend skills.

When to Hire a React Specialist

A React specialist is the right hire when:

• You already have backend coverage. If you have a Node/Django/Rails backend developer, hiring a React specialist rather than another full stack adds more net capability — deeper frontend work rather than redundant backend.
• Performance is a core product differentiator. Consumer apps, data visualisation tools, and complex UIs benefit from a developer who has spent years on React-specific optimisation (memo, virtual DOM, bundle size, Core Web Vitals).
• Your frontend is genuinely complex. Design system ownership, accessibility compliance, complex state machines, and multi-theme applications benefit from specialist depth.
• You are at a scale where role specialisation makes sense. Typically 10+ person engineering teams benefit from specialists; smaller teams usually need breadth.

When to Hire a Full Stack Developer

A full stack developer is the right hire when:

• You are building an MVP or early-stage product. One developer who can build the React frontend and the Node API eliminates the coordination overhead between two specialists — critical when speed matters most.
• Your team is small (under 8 engineers). Breadth typically beats depth at small team sizes. Everyone on a 3-person engineering team should be able to review any part of the codebase.
• Your backend is simple. If your backend is primarily CRUD operations with standard authentication, you don’t need a backend specialist — a full stack developer handles this well.
• You need one person to own a feature end to end. Full stack developers can take a feature from database schema to API to UI without handoffs.

How to Test Each Role Properly

Testing a React specialist (beyond “have you used React”):

• Ask them to explain when they would and wouldn’t use useCallback, and what happens if you overuse it
• Have them review a component with a performance issue (unnecessary re-renders) and describe the fix
• Ask about their approach to TypeScript for complex component props (discriminated unions, generic components)

Testing a full stack developer (the backend side often gets skipped):

• Ask them to design the database schema for a multi-tenant SaaS application — what tables, what foreign keys, how do you handle tenant isolation
• Ask how they would structure API error handling and what HTTP status codes map to what situations
• Have them explain N+1 queries and show how they would identify and fix one