Senior Frontend Developer in Châtenay-en-France, Île-de-France at Jobgether

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Frontend Developer based in France.

This is a senior frontend engineering opportunity focused on building a high-performance web experience from the ground up.
You will shape the frontend architecture using SvelteKit, Svelte, Tailwind CSS, and modern TypeScript.
The role has a strong emphasis on speed, accessibility, SEO, and measurable Core Web Vitals performance.
You will establish scalable engineering standards, reusable components, testing practices, and frontend developer experience.
Working closely with product, design, and backend teams, you will turn complex requirements into clean, maintainable interfaces.
You will also embrace agentic AI development workflows and use AI coding tools as an integral part of your engineering process.
This is a fully remote European role offering significant ownership within a modern, fast-moving technology environment.

As a senior frontend engineer, you will own key technical decisions while establishing a strong foundation for a scalable and performance-focused frontend.

• Architect and develop a new web frontend from the ground up using SvelteKit and Tailwind CSS.
• Define appropriate rendering strategies across SSR, SSG, ISR, and edge computing.
• Establish and maintain performance targets, including LCP below 2.0 seconds, INP below 200ms, and CLS below 0.1 based on real-user data.
• Build and maintain a reusable Svelte component library and scalable design system.
• Translate product requirements and design specifications into clean, composable, responsive, and accessible components.
• Own frontend SEO fundamentals, including semantic HTML, metadata, structured data, sitemaps, and canonicalization.
• Establish frontend testing standards using Vitest for unit testing and Playwright for end-to-end testing.
• Define development tooling and developer experience practices, including linting, formatting, type checking, pre-commit hooks, and CI quality gates.
• Lead code reviews and continuously improve frontend engineering quality and standards.
• Drive technical planning, architecture decisions, ADRs, and broader frontend discussions.
• Integrate frontend applications with backend APIs and contribute to API contract design when relevant.
• Support CI/CD workflows and deployments across AWS infrastructure.
• Monitor, analyze, and optimize frontend performance using tools such as Lighthouse, WebPageTest, and real-user monitoring.
• Incorporate agentic AI development tools into day-to-day engineering workflows to improve delivery speed and effectiveness.

Requirements:

The ideal candidate combines strong frontend engineering expertise with architectural ownership, performance awareness, and a modern approach to software development.

• Strong professional experience building production applications with Svelte and SvelteKit.
• Expert-level knowledge of TypeScript and modern JavaScript.
• Deep experience with Tailwind CSS, including design tokens and scalable approaches that prevent utility sprawl.
• Strong command of HTML5, CSS3, responsive design, and web accessibility.
• Proven experience developing high-performance web applications measured against Core Web Vitals.
• Demonstrated ability to design scalable frontend architectures in greenfield environments.
• Experience creating and maintaining reusable component libraries and design systems.
• Strong understanding of Svelte state management patterns, including stores, context, and runes.
• Hands-on experience with Vitest and Playwright.
• Strong Git and GitHub workflow knowledge, including pull requests, code reviews, and CI/CD.
• Experience with frontend performance monitoring, profiling, and optimization.
• Practical experience implementing agentic development workflows with tools such as Claude Code, Cursor, or equivalent.
• Experience with edge runtimes such as Cloudflare Workers or AWS Lambda@Edge is a plus.
• Experience deploying applications to AWS services such as CloudFront, S3, or ECS is advantageous.
• Experience building CI/CD pipelines and implementing design systems end to end is beneficial.
• Experience integrating AI-powered functionality into production web applications is a plus.
• Previous experience migrating applications from React/Next.js to Svelte/SvelteKit is advantageous.

Benefits:

• Fully remote position within Europe.
• Full-time employment with a daytime working schedule.
• Opportunity to build and scale a B2B technology platform from the ground up.
• Up to 28 days of annual leave, in addition to public holidays.
• Truly global remote environment with colleagues working across different regions.
• Significant ownership over frontend architecture, engineering standards, and product performance.
• Opportunity to work with modern technologies including SvelteKit, Tailwind CSS, TypeScript, AWS, and AI-assisted development tools.
• Exposure to greenfield architecture, performance engineering, design systems, accessibility, SEO, and modern testing practices.
• Collaborative environment working closely with product, design, backend, and other technical stakeholders.
• Opportunity to influence the long-term technical direction of a growing platform