We are looking for a Middle Full Stack Developer with strong React and Node.js expertise to help build a greenfield member and community platform for a large professional association. This role requires strong system design and integration skills, hands-on use of AI-assisted development tools, and a clear understanding of data and compliance constraints. We expect strong ownership and the ability to move fast from prototype to production.
About the project: We’re building a member and community platform for a large not-for-profit professional association (~25,000 members across Europe). It replaces a fragmented stack of legacy tools and manual spreadsheet workflows with a single product where members sign up once, discover and register for events, pay online, network in topic communities, and check in on-site — with everything syncing automatically into the organisation’s CRM. The product ships as a responsive web app and native mobile apps from one codebase, plus an admin back-office.
Responsibilities * Design and develop full-stack applications using Node.js/NestJS and React 19 + TypeScript; * Implement core domain features: credit-ledger integrity, real-time chat/community feeds, RBAC, event registration, and QR check-in flows; * Build and maintain integrations with third-party services — Stripe (checkout, memberships, webhooks), Zoho CRM & Analytics, Zoom/Teams; * Build backend APIs and services for secure, GDPR-compliant data access; * Implement AI-driven features as part of the post-MVP roadmap; * Design and maintain prompt engineering strategies, including context management, token optimization, and output quality control, where applicable; * Build systems that efficiently manage context windows, embeddings, and structured/unstructured data for AI features; * Implement data aggregation, transformation, and enrichment pipelines (e.g., CRM sync jobs, background processing via SQS); * Ensure performance, scalability, reliability, and observability of data-heavy and AI-heavy services; * Rapidly prototype features using AI-assisted development tools; * Collaborate closely with product owners and the wider team; * Take technical ownership, perform code reviews, and mentor other engineers; * Ability to travel internationally for individual client meetings.
Requirements * 3+ years of professional software development experience; * Strong backend expertise with Node.js (NestJS, Express, or similar); * Strong frontend expertise with React (React 19 experience a plus) and modern JavaScript/TypeScript; * Solid system design skills and experience building production-grade systems, including monorepo architecture (e.g., Nx, Turborepo, or similar), multi-surface systems (web + mobile); * Hands-on experience integrating LLMs and AI services; * Strong understanding of prompt engineering, token limits, context windows, and cost/performance trade-offs; * Experience with data aggregation, transformation, and data engineering pipelines; * Experience with SQL and NoSQL databases (PostgreSQL experience a plus); * Understanding of data privacy and compliance principles (GDPR or similar); * Ability to work fast, prototype effectively, and deliver high-quality solutions; * Strong ownership mindset, leadership skills, and sense of urgency; * Upper-Intermediate or higher English level; * Ability to travel internationally for individual client meetings if needed.
Nice to have * Experience with Capacitor or other cross-platform mobile frameworks (React Native, etc.); * Experience with payment systems (Stripe or similar) and financial/ledger integrity; * Experience with real-time systems (WebSockets, chat, live feeds); * Experience building secure, compliant systems (GDPR or similar); * Experience building RAG systems, embeddings pipelines, and knowledge bases; * Experience optimizing AI systems for latency, accuracy, and cost; * Background in data engineering or ML-adjacent roles; * Experience with AWS infrastructure (RDS, S3, SQS, CloudFront, WAF).
We offer * Competitive compensation based on your skills, experience, and performance; * 20 working days of paid annual vacation and 5 days of sick leave; * 3 additional days off for special occasions; * Experienced colleagues with 95% of middle and senior engineers; * Possibility to work from anywhere in the world; * Exciting projects involving the newest technologies; * Accounting as a service; * Flexible working approach.
