Frontend Software Engineer

Location: Poland We Are:  RTB House is a next-generation performance demand-side platform (DSP) that uses proprietary Deep Learning AI algorithms to help brands grow. The company is the market leader in driving performance using Deep Learning across the entire purchase funnel.  Founded in 2012, and now operating in 90+ markets, RTB House has always been private-by-design. It embraces first-party advertising and a relentless approach to innovation. RTB House offers end-to-end Deep Learning-powered AdTech products and solutions to maximize conversion, drive new customer acquisition, create engagement, and fuel long-term demand for a global base of clients.  As a Frontend Software Engineer, you will join our Product Tools team, building a dozen or so single-page applications that are used to configure, monitor, analyze, and automate advertising campaigns, as well as support various internal company processes. You Will: • Design and implement advanced user interfaces, such as forms divided into nested, sortable sections with drag & drop support; • Build configurable table views with user-defined column visibility, ordering, and data filtering based on individual preferences; • Develop reusable UI components used system-wide by multiple teams - for example, an advanced virtualized DataGrid and many others; • Work with an interdisciplinary product team, including QA engineers, Product Designers, Backend Developers, and DevOps specialists; • Take part in code reviews and team-based frontend architecture design - we care deeply about code quality, consistency, and continuous improvement; • Use AI tools (LLMs, coding assistants) to speed up writing test scripts, generating edge-case data, and documenting created artefacts. Requirements: Must have • 5+ years of commercial experience in building scalable, high-performance web applications, with a strong focus on React; • Proficiency in JavaScript and TypeScript; • Practical experience in writing unit tests using tools such as Testing Library, Vitest, or Jest; • Solid understanding of frontend-backend communication, including REST APIs and GraphQL; • Experience with data management and caching libraries like Apollo Client and/or TanStack Query; • Strong knowledge of HTML and CSS (including Flexbox and CSS Grid); • Experience using AI to work smarter; • Fluency in English and Polish (C1 level or above). Nice to have • Awareness of UX/UI best practices - a product-oriented mindset significantly improves delivered solutions; • Willingness to proactively suggest architectural or technical improvements. • Experience with Storybook or similar tools for developing and documenting UI components; • Basic knowledge of databases (e.g. SQL) - understanding how data is structured and queried helps in designing more effective UIs. Selected Technologies: • React with TypeScript • Apollo Client (GraphQL) & TanStack Query (REST) • Vite / Vitest / Testing Library • Storybook • GitHub • Sentry We Offer: • Projects focused on high code quality - solid code reviews are our standard; • Collaboration within an interdisciplinary, self-sufficient team including: DevOps (ensuring a great Developer Experience), database experts, backend developers, product designers, and QA engineers; • Hardware and software tailored to your preferences - e.g. MacBook, AI tool licenses; • Access to modern technologies and the opportunity to apply them in large-scale, high-impact projects; Apply now!  You don't need to tick every box to apply. If you are passionate about digital marketing, send us your CV, and we'll review it.