Client 360 Full-Stack Application Developer (React.js, Javascript, GraphQL), Assistant Vice President

State Street is a global organization helping institutional investors manage risk and drive performance. The role is within a modern platform built with a start-up energy but enterprise scale, in an international and collaborative environment.

• Strong experience building service layers and APIs (REST/GraphQL), secure and scalable.
• Experience with Node.js (Express/NestJS) and TypeScript.
• Experience with Java (Spring Boot).
• Solid experience with React.js, modern JavaScript/TypeScript, component patterns, and API integration.
• Experience with databases like PostgreSQL, SQL Server, MySQL, MongoDB, and data modelling.
• Strong discipline in unit testing and integration testing.
• Familiarity with CI/CD, code quality tools, and modern DevOps practices.
• B.S. degree (or equivalent) in Computer Science, Engineering, Mathematics, Physics, or technical fields; MS degree strongly preferred.
• Minimum 8-10 years of related experience.
• Good written and verbal communication skills in English are mandatory.
• Ability to collaborate across functions and geographies.
• High engagement and willingness to enter into contract for employment.

Services Layer / Backend (Primary Focus):

• Design, build, and maintain service-layer components including RESTful APIs and/or GraphQL.
• Implement authentication/authorization, request validation, error handling, and consistent API contracts.
• Develop data access and persistence logic using SQL and/or NoSQL stores; optimize performance and reliability.
• Build integration patterns (event-driven, async messaging, batch, streaming) using tools like Kafka or MQ.

UI / Front-End (React.js):

• Develop and maintain UI features using React.js, TypeScript, and modern state management patterns.
• Collaborate with design/UX for reusable components, accessibility, and responsive experiences.
• Integrate UI with backend services via APIs; implement client-side validation and error handling.

Candidates must be willing to enter into a contract for employment. English language skills are mandatory. This offer is for candidates able to work in Krakow, Poland, with a hybrid work model including office presence.