Senior Frontend Developer

🏢 Summary: Senior Frontend Engineer role building enterprise AI interfaces and production Next.js applications with complex state, real-time functionality, and scalable frontend architecture. The position is fully on-site in Warsaw city centre, five days per week, with responsibility for UI quality, performance, accessibility, and enterprise-grade features. 🗂️ Requirements: Work on-site in Warsaw city centre 5 days per week, 5+ years of frontend development experience, 3+ years of React and TypeScript experience, Production Next.js experience, App Router and Server Components expertise, SSR, SSG and CSR knowledge, Complex state-management experience, Real-time and multi-tenant application experience, AI or LLM interface experience, Frontend performance and Core Web Vitals expertise, Accessibility, localization and frontend security knowledge, Experience handling sensitive data, Experience using AI coding assistants 📃 Skills: React, TypeScript, Next.js, SSR, SSG, CSR, LLM, AI, CoreWebVitals, Accessibility, Localization, Security, Claude, Codex, Copilot 🏢 Description: Please note: This role requires working from our office in Warsaw city centre 5 days a week . This is a fully on-site position , and remote or hybrid work is not available . About us We believe that businesses are moving toward AI-powered work, and we are building a platform for this future. Many AI agents cannot handle complex business tasks. We created a platform that organizes company policies, workflows, and business knowledge into one AI data model. This helps AI agents make accurate decisions and deliver reliable results at scale. We already work with well-known enterprise customers such as Glovo, Nespresso, and HelloFresh. Our platform supports thousands of users and processes real production data. Customers trust us with important business knowledge because we provide a secure and reliable solution with SOC2, HIPAA-ready security practices, and strong integrations. Job description We are looking for a Senior Frontend Engineer who enjoys building high-quality user interfaces for enterprise AI products. In this role, you will design and build important frontend features, solve complex UI problems, and improve the user experience over time. You will take ownership of frontend architecture and help build production Next.js applications with complex state management, real-time AI features, and enterprise functionality. The position is based in Warsaw and requires working from the office. Responsibilities Design and build production Next.js applications that support complex state, high traffic, and real-time AI features. Create user interfaces for AI-powered tools, including streaming AI responses, semantic search, knowledge graphs, and AI agents. Build and improve our component library and design system to keep the user experience consistent, accessible, and reusable. Deliver enterprise features such as localization, accessibility, browser compatibility, and security. Monitor applications after release, improve performance, reduce bundle size, track Core Web Vitals, and help systems scale. Maintain high engineering standards through code reviews, testing, and mentoring other developers. Requirements More than 5 years of frontend development experience, including at least 3 years working with React and modern TypeScript. Strong experience building production applications with Next.js, including App Router, Server Components, and understanding SSR, SSG, and CSR. Experience managing complex application state, including real-time updates, optimistic UI, multi-tenant systems, and large amounts of data. Experience building AI or LLM-based interfaces such as chat applications, streaming responses, or semantic search. Strong knowledge of frontend performance and experience improving Core Web Vitals in large applications. Good understanding of accessibility, localization, security, and enterprise application standards. A security-focused approach and experience working with sensitive data. Strong product thinking and the ability to improve user experience without waiting for detailed designs. Experience using AI coding assistants as part of your daily development work. Good written and spoken communication skills and the ability to explain technical decisions clearly. Nice to have Experience with React Flow, Highcharts, or other data visualization libraries. Experience building vector search, RAG, generative AI, or semantic search interfaces. Basic knowledge of Node.js or Python to understand backend code and APIs. Experience contributing to design systems or open-source UI libraries. What we offer B2B contract and company stock options. MacBook Pro. Modern technology stack and the opportunity to contribute to open-source projects. An AI-focused development environment with tools such as Claude Code, OpenAI Codex, and GitHub Copilot. Our values Our leadership team has strong experience in AI, knowledge management, and enterprise SaaS. We have received more than $60 million in funding and have been recognized by Gartner as a Cool Vendor. Our work is guided by these values: Quality – We care about excellent work and high standards in everything we build. Momentum – We take initiative, share ideas, and keep moving forward. Accountability – We take responsibility for our work and give honest, respectful feedback. Hard work – We believe success comes from teamwork, dedication, and consistent effort. Learning agility – We stay curious, learn from mistakes, and continue improving. Adapt and thrive – We welcome change and see challenges as opportunities to grow. Win together – We work as one team, communicate openly, and support our shared goals.

🏢 Summary: Senior Frontend Developer role focused on owning frontend architecture and delivering high-performance React applications for business-critical web systems. The offer requires full-time onsite work and includes technical leadership, API integration, modernization, and mentoring responsibilities. B2B rate: 110–140 PLN per hour. 🗂️ Requirements: Full-time onsite availability, 5+ years of professional programming experience, Strong React experience, Excellent TypeScript knowledge, Deep understanding of React state management and rendering, HTML5, CSS3 and responsive-design proficiency, Strong TailwindCSS experience, Understanding of authentication and authorization flows, Frontend security and performance-optimization knowledge, Frontend architecture design experience, Experience diagnosing performance and rendering issues, Git proficiency and professional development workflows, Agile team experience, Effective use of AI-assisted development tools, English at B2+ level 📃 Skills: React, TypeScript, HTML5, CSS3, TailwindCSS, REST, GraphQL, Git, Agile, AI, Security, Authentication, Authorization, Performance 🏢 Description: 📍 Warsaw (Onsite – near Metro Plac Wilsona)💼 B2B About Silk Software House Silk Software House builds and maintains business-critical web applications for fintech, payments, and enterprise clients. We value ownership, strong technical judgment, and developers who can design solutions, not just implement tasks. Your Role As a Senior Frontend Developer, you’ll take responsibility for frontend architecture, make key technical decisions, and ensure long-term code quality and performance. You’ll collaborate closely with backend teams and help shape how frontend systems are built and evolved. Responsibilities Design and build frontend architecture for web applications Develop complex React applications using TypeScript Make and justify architectural and technical decisions Optimize performance, rendering, and user experience Define and enforce frontend best practices and coding standards Integrate frontend systems with REST / GraphQL APIs Review code and support less experienced developers Collaborate with architects, backend developers, and product stakeholders Support existing projects through modernization and optimization Requirements This role requires full-time onsite work (no remote or hybrid options). Candidates must be willing and able to work from our office near the Plac Wilsona metro station 5+ years of professional programming experience , including strong React experience Excellent knowledge of TypeScript Deep understanding of React , state management, and rendering behavior Very good knowledge of HTML5, CSS3 , and responsive design Strong experience with TailwindCSS Solid understanding of authentication and authorization flows Good knowledge of frontend security and performance optimization Experience designing and building frontend architectures Experience diagnosing complex performance and rendering issues Familiarity with Git and professional development workflows Experience working in teams using Agile methodologies Ability to use AI-assisted development tools effectively English at B2+ level , enabling smooth communication Nice to Have Next.js Accessibility standards ( WCAG ) E2E testing frameworks CI/CD pipelines Storybook i18n support in production applications Rates (B2B) 110–140 PLN / hour Recruitment Process Intro call (30 min) Senior-level technical interview Architecture & decision-making discussion Offer