Senior AI Fullstack Engineer (Next.js & LLM)

Nasze wymagania: 8+ years of experience as a consultant / forward deployed engineer Strong experience with Next.js (App Router), React, TypeScript Deep understanding of: Server vs Client Components (RSC), streaming, caching, revalidation, Server Actions Vercel AI SDK / LangGraph / MCP Experience building RAG systems Claude extended thinking / prompt caching / Batch APIs Proven experience shipping LLM-powered features to production Hands-on with Anthropic / OpenAI APIs (messages, tool use, streaming) Practical experience with: prompt engineering (structured output, few-shot, XML), tool calling / agent workflows, multi-turn orchestration Understanding of: token economics (input/output costs, context window), latency vs quality trade-offs Experience with: prompt evaluations (LLM-as-judge, rule-based), handling hallucinations and failure modes Ability to design robust AI systems, not just prototypes Strong ownership mindset Experience working directly with clients Clear communication and structured thinking (English C1) Ability to make decisions in ambiguous environments O projekcie: We are expanding our AI capabilities—autonomous agents, AI-driven automation, and LLM-powered workflows—and are looking for a Senior AI Fullstack Engineer who can design and ship production-ready AI systems. You will work at the intersection of modern web architecture and generative AI, taking ownership of solutions delivered to real users. Zakres obowiązków: Ship Production Apps: Build scalable web applications using Next.js (App Router) and TypeScript, ensuring high performance and clean architecture. Engineer AI Workflows: Develop and orchestrate LLM-powered features using Anthropic and OpenAI APIs, focusing on tool use and streaming. Agentic Orchestration: Design autonomous agent loops and multi-turn workflows, knowing when to use a structured pipeline versus a dynamic agent. Optimize & Evaluate: Manage token economics (pricing, context windows) and implement prompt evaluations (LLM-as-judge, rule-based) to ensure system reliability. Collaborate: Work directly with senior engineers, founders, and client teams to shape AI capabilities from concept to production. Oferujemy: B2B: 120 – 180 PLN/h + VAT 🔥 100% remote (Poland) 29 paid vacation days Private healthcare + sports card High-impact work on real AI systems