Senior Web Developer (Client Portal)

About Exegy Exegy is a global leader in intelligent market data, advanced trading systems, and future-proof technology. Exegy serves as a trusted partner to the complete ecosystem of buy-side firms, sell-side firms, exchanges, and financial-services technology companies around the globe. Headquartered in St. Louis, with regional offices across North America, the UK and Europe, and Asia Pacific, Exegy has the global footprint to deliver world-class technology, support, and managed services to elite financial-market participants. Job Summary Exegy is seeking a Senior Web Developer to take a leading technical role in the architectural evolution, modern front-end development, and full-stack ownership of our client portal. In this role, you will assess our existing web platform, guide technical decisions, and deliver responsive, secure, and scalable web applications that redefine how global financial clients interact with Exegy services. You’ll combine sharp front-end engineering skills with solid API integration experience, working closely with Product, Engineering, and Client Services to translate business needs into sleek, production-ready web solutions. Location St. Louis, MO | Montreal, Canada | Belfast, UK (Hybrid) Responsibilities Take technical ownership of Exegy’s client portal, driving front-end architecture, API integrations, and ongoing web platform development Assess technical debt, web performance, UI/UX responsiveness, and existing front-end/backend integrations Design and build responsive, client-facing features using modern JavaScript/TypeScript frameworks (React, Vite) Develop and maintain robust backend API integrations and microservices using Python, FastAPI, or Node.js Establish scalable web development standards, including automated unit/E2E testing, CI/CD pipelines, and cloud deployments Partner with Product Management to turn wireframes, user flows, and business requirements into intuitive web applications Elevate application security, accessibility, cross-browser compatibility, and runtime performance Troubleshoot complex client-side and server-side production issues, conducting root-cause analysis and implementing lasting fixes Provide code reviews, front-end minting, and technical mentorship to peer engineers Qualifications Strong professional track record as a Web Developer or Full-Stack Web Engineer delivering production-grade web applications Advanced proficiency in JavaScript, TypeScript, and modern front-end frameworks (React strongly preferred) Solid experience designing, consuming, and maintaining RESTful APIs and backend web services Proficiency with Python (FastAPI/Flask) or Node.js for backend development Experience with relational databases, web application security (OAuth, JWT, CORS), and state management Mastery of modern web standards, CSS/HTML architecture, responsive design, and web performance optimization Hands-on experience with version control (Git), automated testing (Jest, Cypress, Playwright), and CI/CD pipelines Strong communication skills and the ability to work across technical and nontechnical teams Demonstrated ownership of complex technical projects or production applications Preferred Qualifications Experience with React, TypeScript, and Vite build tooling Experience developing B2B SaaS platforms, enterprise portals, or financial dashboards Background in fintech, capital markets, or market-data technology Exposure to cloud deployments (AWS/Azure) and application monitoring tools Experience in financial services, capital markets, fintech, or market-data technology Experience working within globally distributed engineering teams