Senior Fullstack Engineer (Next.js/AI Agents)

Job SummaryKakegroup is hiring a remote candidate for Senior Fullstack Engineer (Next.js/AI Agents). This is a contract position. Work location: USA. The role typically involves technologies such as React, Next.js, REST, Figma, Design Systems, Artificial Intelligence (AI). We're looking for a product-minded fullstack engineer to join a fast-moving team building AI-powered products at the intersection of great UX and applied AI. This role is heavy on product thinking, UI craft, and building with multi-agent systems and LLMs - not on infrastructure or distributed systems work. You'll be working across a modern Next.js/React stack while designing agentic workflows and MCP server integrations, so strong instincts for both clean interfaces and reliable AI system design are essential. This is a great fit for someone who loves building polished, delightful products and is excited to work at the leading edge of applied AI (multi-agent systems, RAG, voice agents). Key ResponsibilitiesDesign, build, and ship fullstack features across the product, from UI to backend logic Build and maintain agentic workflows, including multi-agent systems and MCP server integrations Collaborate closely with design to implement polished, animated, high-quality UI using Material UI and Figma specs Build and maintain RAG pipelines and integrations with multiple LLM providers (Gemini, GPT, Claude, Perplexity) Work with async job processing (Inngest) and Postgres-backed data models Contribute to internal tooling and back-office workflows (Retool) Partner with product and design to translate requirements into technical solutions Write clean, maintainable code and participate in code review Core RequirementsStrong experience with Next.js (Pages Router) and React 18 Experience building and reasoning about multi-agent AI systems and agentic workflows Solid backend experience with Postgres and building APIs (e.g., Next.js API routes) Strong product sense and a genuine interest in UI quality, animation, and design systems Experience integrating with LLM APIs ( e.g., OpenAI, Anthropic, Gemini) and/or RAG pipelines Excellent written and verbal communication skills in English Ability to work independently in a remote, fast-paced environment Nice-to-HaveExperience designing or building MCP (Model Context Protocol) servers Experience building voice agents Familiarity with Material UI and translating Figma designs into production UI Experience with async job frameworks like Inngest Familiarity with Qdrant or other vector databases for RAG Experience using AI coding tools like Codex or Claude Code Experience with Retool or similar internal tooling platforms Additional US Timezone OverlapRequired overlap with 9am-3pm PT (GMT-7) Product-Focused RoleThis role is not infrastructure-heavy - you won't be working on massive distributed systems or large-scale data problems. The ideal candidate is more energized by product craft, UI polish, and applied AI than by backend scale challenges. Salary$0 - $0 a year Contract Typecontract position. Seniority LevelSeniority level: Senior. Hiring Process DisclaimerWe may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses and identifying potential inconsistencies or verification signals in application materials based on available information. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us. SkillsSkills required for this role include React, Next.js, REST, and related tools for day-to-day development.#J-18808-Ljbffr