Senior Frontend Engineer
Employment Information
Report this job
Job expired or something wrong with this job?
Job Description
Senior Frontend Engineer building React interfaces, collaborative flow tools, and BFF systems for an AI agent platform. Owning design systems, testing, and microservice integrations.
Responsibilities:
- Build and evolve React interfaces for an AI agent platform, including conversation and prompt engineering tools, graph-based collaborative flow builders, agent configuration and testing interfaces, and call analytics dashboards
- Own and develop the BFF layer on NestJS, aggregating REST microservices through typed clients generated from OpenAPI
- Handle authentication, pagination, streaming, and error contracts to keep the frontend layer thin
- Contribute to backend development with PostgreSQL and Redis
- Drive the evolution and consistency of the frontend component ecosystem
- Consolidate legacy Ant Design components into a design system built on Mantine
- Own the shared UI library and Storybook and keep multiple product applications consistent
- Ensure product quality through Vitest unit/component tests and Playwright end-to-end and critical user-flow testing, including SDK functionality
- Collaborate across teams and product v-teams on API contracts, SDK protocols, code reviews, bug fixes, QA support, and test scenarios
- Partner with the documentation team to create and maintain integration guides and practical code examples
Requirements:
- 6+ years of professional experience in frontend/full-stack product development
- 5+ years of React in production
- Strong senior-level expertise in TypeScript, including strict mode, React 19, Vite, and monorepos
- 2+ years of Node.js development on the server
- Hands-on experience building and operating BFF or API gateway layers
- Understanding of service aggregation, authentication, pagination, error contracts, and clear BFF boundaries
- Strong production experience in microservice environments, ideally working with 10+ services
- Experience building complex, stateful UIs such as graph/canvas editors or collaborative interfaces
- Experience with undo/redo, optimistic updates, conflict handling, and non-trivial state management
- Frontend architecture and code organization skills; familiarity with FSD or modular/layered architectures
- Product sense and autonomy in making UI and UX decisions from product context and an existing design system
- Hands-on experience writing and maintaining unit/component tests with Vitest
- End-to-end testing experience with Playwright
- Experience with React Query, Socket.io, Prisma, and PostgreSQL
- Hands-on experience with AI-assisted development tools such as Claude Code, Cursor, Codex, GitHub Copilot, or similar
- Experience with NestJS is a strong plus
- Experience owning or maintaining shared component libraries or migrating legacy UIs to new design systems is nice to have
- Experience with Yjs, Automerge, operational transforms, WebRTC, SIP, Kubernetes, Helm, OpenTelemetry, Prometheus, Prisma, Kysely, or PostgreSQL query optimization is nice to have
- Domain experience in voice AI, telephony, contact centers, conversational AI, or LLM-based products is nice to have
Benefits:
- The team has built award-winning AI products for tech corporations - devices, voice assistants, products that are actually in the world
- Cutting-edge tech stack: Speech Technologies, NLP, Generative AI (LLMs, diffusion models), voice-first agentic architecture with privacy-first and on-premises deployment
- High engineering bar and real ownership - the team cares about what actually works in production, not what looks good in a demo, and you'll see the impact of your work directly
- Fast career progression - a senior-heavy team and a high volume of real problems means you grow faster than you would anywhere else
- Startup pace with enterprise stability - real clients, real revenue, no bureaucracy
- Fully remote across Europe
- 21 vacation days + public holidays + 5 sick days
- Private English lessons via Preply
Similar Jobs
Senior Frontend Engineer
Senior Frontend Engineer building React interfaces, collaborative flow tools, and BFF infrastructure for an AI agent platform. Owning design systems, testing, and microservice integrations.
Senior Frontend Engineer
Senior Frontend Engineer building React interfaces, collaborative flow tools, and NestJS BFFs for an AI agent platform. Evolving Mantine design systems and testing product experiences.
Frontend Engineer
Frontend Engineer building enterprise web applications for SupplyHouse.com, an HVAC, plumbing, heating, and electrical supplies e-commerce company. Improving interfaces, performance, accessibility, and user experience.
Web Developer, Marketing AI
AI web specialist turning generated concepts into branded, production-ready CMS experiences for GoEngineer’s engineering and 3D-printing technology business. Supporting HubSpot, Shopify, Celigo, and front-end development.
UI Engineering Lead
UI Engineering Lead building responsive C++ and Unreal Engine interfaces for PlayStation’s new game franchise. Leading UI engineers and shaping player experiences with a cross-disciplinary team.
Frontend Web Application Developer
Frontend developer building KoboToolbox’s TypeScript and React survey applications. Improving a global data-collection platform used by humanitarian organizations and thousands of partners.
Frontend Developer
Frontend Developer building responsive web applications and design systems for FyerX's internal platforms and client technology transformations. Translating Figma designs into accessible, high-performance interfaces.
Junior Front-end Developer
Junior Front-end Developer building responsive Pharma and Life Sciences digital content for Viseven. Creating eWizard presentations, landing pages, emails, animations, and web components.
Junior Front-end Developer
Junior Front-end Developer creating responsive digital content for Viseven, a global B2B MarTech provider serving Pharma and Life Sciences. Building eWizard presentations, landing pages, emails, animations, and web components.
Junior Front-end Developer
Junior Front-end Developer creating responsive digital content for Viseven, a global B2B MarTech provider serving Pharma and LifeScience companies. Building eWizard presentations, landing pages, emails, animations, and web components.
Junior Front-end Developer
Junior Front-end Developer creating responsive digital content for Viseven, a global B2B MarTech provider serving Pharma and Life Sciences. Building eWizard pages, emails, animations, and components.
Junior Front-end Developer
Junior Front-end Developer creating responsive digital content for Viseven, a global B2B MarTech provider serving Pharma and Life Sciences. Building eWizard presentations, landing pages, emails, animations, and web components.
Junior Front-end Developer
Junior Front-end Developer creating responsive digital content for Viseven, a global B2B MarTech provider serving Pharma and Life Sciences. Building eWizard pages, emails, animations, and interactive tools.
Web Developer
Web Developer building secure full-stack federal applications for Capgemini Government Solutions. Developing C#/.NET web apps, APIs, databases, and modern interfaces for federal programs.
Frontend Engineer, Ads
Frontend Engineer building high-impact, interactive ad formats for Reddit’s community platform. Developing responsive web experiences and AI-driven advertising solutions at scale.
Senior Fullstack Engineer – C#, React
Senior full-stack engineer building scalable cloud-native B2B SaaS solutions for Nortal, a digital transformation and AI services company. Developing C#/.NET, React, microservices, APIs, and cloud platforms.
Frontend Developer, React
Desarrollador Frontend React para proyectos de ecommerce, telecomunicaciones y Optimizely en knowmad mood. Construcción de aplicaciones web escalables con arquitecturas frontend modernas.
Frontend Developer, React – iGaming
Frontend React Developer building responsive, scalable interfaces for a growing online betting platform. Developing React features, optimizing performance, and collaborating remotely with product teams.
Frontend Engineer
Frontend Engineer building reusable React/Angular interfaces for Qualysoft’s international IoT platform. Integrating REST APIs, real-time telemetry, and Figma design systems.
Senior Frontend Developer – All Genders
Senior Frontend Developer building Contabo’s new cloud hosting product line. Creating customer-facing interfaces and tooling with TypeScript, Svelte, APIs, and modern frontend infrastructure.