Full-Stack Engineer (React / Next.js / TypeScript) vs Principal Software Engineer: Salary & Career Benchmarks in France

In France, Principal Software Engineer roles typically command a higher median salary than Full-Stack Engineer (React / Next.js / TypeScript) positions. According to our 2026 live benchmark data, a mid-level Principal Software Engineer earns a median salary of €88K, whereas a Full-Stack Engineer (React / Next.js / TypeScript) brings in roughly €60K (a gap of €28K at the median).

Seniority, tech stack, and location all move this gap. Senior practitioners in either discipline can exceed the upper range through specialist skills. See the skills premium section below for the specific certifications and tools that push offers to the top of the range.

While both positions are vital to a modern tech organisation, Full-Stack Engineer (React / Next.js / TypeScript) and Principal Software Engineer have fundamentally different daily workflows.

Full-Stack Engineer (React / Next.js / TypeScript) focuses primarily on building end-to-end product features across a React/Next.js front end and its supporting backend services, typically in TypeScript throughout. Day-to-day work revolves around building UI components in React and Next.js, writing and consuming backend APIs in TypeScript, optimising for performance and SEO where relevant, and collaborating closely with design and product.

Principal Software Engineer focuses on driving technical direction, architecture decisions, and engineering standards across multiple teams. Their time is spent writing and reviewing RFCs, prototyping architectural solutions, mentoring senior engineers, driving cross-team technical alignment, and contributing to complex code in the highest-risk areas of the codebase.

Transitioning between these two paths is achievable but requires targeted upskilling.

Moving from Full-Stack Engineer (React / Next.js / TypeScript) to Principal Software Engineer: Senior Software Engineers who have demonstrated impact beyond their immediate team, driven architectural decisions, and mentored others are the standard path. The jump requires a mindset shift from team-level to org-level impact.

Moving from Principal Software Engineer to Full-Stack Engineer (React / Next.js / TypeScript):

Neither path requires starting from scratch. Professionals in both roles share underlying technology fluency; the gap is usually domain knowledge and specific tooling rather than core engineering fundamentals.

In France in 2026, both roles are seeing demand, but with different drivers.

Full-Stack Engineer (React / Next.js / TypeScript) demand is very high, particularly in Paris and Lyon SaaS and fintech scale-ups building product on modern React/TypeScript stacks, led by employers such as Doctolib and Criteo. Principal Software Engineer demand is high, concentrated in Enterprise software and fintech engineering organisations in Paris and Toulouse, led by employers such as Dassault Systemes and Criteo.

Workspace flexibility significantly impacts total compensation value in France.

Full-Stack Engineer (React / Next.js / TypeScript) roles score 65% on our remote-friendliness index (High). This is because full-stack product work is largely async-friendly, though French labour law's right-to-disconnect provisions typically cap remote schedules at two or three days a week. Where in-office attendance is required, it is typically driven by close collaboration with design and product on fast-moving features still pulls engineers into hybrid schedules at most Paris-based scale-ups.

Principal Software Engineer roles score 70% (High). Technical design and deep coding work is async and remote-compatible, and French employers have leaned into remote and hybrid arrangements since teleworking negotiations became standard practice across Paris tech scale-ups is the primary driver of flexibility. When office days are required, it is usually for architectural alignment sessions, mentoring, and cross-team technical reviews benefit from in-person presence, which is why Paris-based scale-ups increasingly schedule fixed in-office days around sprint planning and design reviews.