Senior Full-Stack Engineer

TensorX is a sovereign AI infrastructure platform headquartered in Dublin. We deploy and host open-source large language models on EU-sovereign infrastructure across Europe, providing private, zero-retention inference for regulated industries including finance, healthcare and government. Our platform offers drop-in OpenAI-compatible APIs, enabling developers and enterprises alike to adopt AI without compromising on data privacy, compliance or performance. We are looking for Full-Stack Engineers at various levels to join our growing engineering team. You will take ownership of features across the entire product surface, from our customer-facing dashboard and billing systems through to our backend API services and infrastructure tooling. This is a hands-on, high-impact role in a fast-moving scaleup where your work will directly shape the platform our customers rely on. You will work across multiple projects, primarily in TypeScript, spanning a React/Next.js frontend and a Node.js/Express API layer backed by PostgreSQL and Redis/Valkey. Frontend development is a key part of this role, and you will be responsible for building the interfaces our customers and their agents interact with daily. We are an AI-native team and tools such as Claude Code and Codex are part of our standard workflow, not an experiment. We value engineers who can deliver polished, accessible user experiences while also contributing to robust backend services. Responsibilities Feature Delivery - Design, build and ship end-to-end features spanning the frontend dashboard, REST API and database layers, taking work from specification through to production deployment.Frontend Development - Build responsive, accessible and performant interfaces using React and Next.js with server-side rendering, middleware and modern routing patterns. Implement design systems using headless component primitives and utility-first CSS.Backend & API Development - Develop and maintain RESTful API services in Node.js/Express with full TypeScript type safety. Design relational database schemas and write performant SQL. Implement caching, rate limiting and background job processing.Testing & Reliability - Write and maintain automated tests across the stack, including unit, integration and end-to-end tests.Authentication & Security - Own and evolve authentication and authorisation systems, including JWT-based auth flows, role-based access control and security hardening.Payments & Integrations - Build and maintain third-party integrations including payment processing, cryptocurrency payment flows, transactional email, bot protection and customer messaging.Infrastructure & DevOps - Manage containerised development and deployment workflows using Docker within a cloud-native environment. Maintain CI/CD pipelines and contribute to platform reliability.Code Quality & Collaboration - Participate in code reviews, contribute to architectural decisions and help establish best practices. Skills & Experience 5+ years of professional experience building full-stack web applicationsAdvanced proficiency in TypeScript across frontend and backend codebasesStrong frontend skills with React and Next.js (SSR, App Router, middleware), headless component libraries (e.g. Radix UI, shadcn/ui) and utility-first CSSSolid backend experience with Node.js, Express, PostgreSQL and Redis/ValkeyPractical experience with authentication systems, RBAC and web security practicesFamiliarity with payment platform integration (e.g. Stripe); cryptocurrency payments desirableExperience with Docker and containerised deployment workflowsComfortable using AI-assisted development tools (e.g. Claude Code, Codex) as part of daily workflowClear communicator who thrives in ambiguity Nice to Have Experience with LLMs (prompt engineering, RAG, evaluation and model deployment)AWS (EC2, ECS, S3, Lambda and CloudFront)Python and/or Golang Benefits Highly competitive package, dependent on experience25 days paid annual leaveHybrid working from our centrally located Dublin officeFree inference tokens! ******* NO AGENCY ASSISTANCE REQUIRED *******