Full-Stack Engineer: Backend & React UI (Hybrid)

State Street; Kraków; Hybrid; PLN 118,800 - 145,200; Full time

Benefits offered by this job

Permanent contract from day one

Birthday/anniversary time off

Private medical package

Job summary

State Street is seeking a Full-Stack Application Developer in Kraków to help build the services layer and a React.js UI. You will implement APIs, data access, and integrations while delivering scalable, reliable software in a hybrid work model.

You’ll work across backend and frontend with Node.js/Express/NestJS, Java Spring Boot, and modern frontend tech, collaborating with international teams to ship robust products.

Qualifications

• BS or higher in computer science, engineering, math or physics.
• Experience building service layers and REST APIs with secure scalable design.
• Proficiency with React.js and modern JavaScript/TypeScript.
• Experience with databases (PostgreSQL, SQL Server, MySQL, MongoDB) and data modelling.
• Familiar with CI/CD, code quality tools and DevOps practices.

Responsibilities

• Build and maintain service-layer components, orchestration, and integrations.
• Implement authentication/authorization, validation, error handling, and API contracts.
• Develop data access logic and optimize queries for performance.
• Create UI features with React.js and TypeScript, ensuring accessibility and responsiveness.

Skills

Node.js

TypeScript

React.js

REST APIs

SQL & Databases

Testing (Unit/Integration)

CI/CD / DevOps

Education

B.S. or higher in CS/Engineering/Math/Physics

MS degree preferred

Tools

Kafka

MQ

Job description

State Street is seeking a Full-Stack Application Developer in Kraków to help build the services layer and a React.js UI. You will implement APIs, data access, and integrations while delivering scalable, reliable software in a hybrid work model.

You’ll work across backend and frontend with Node.js/Express/NestJS, Java Spring Boot, and modern frontend tech, collaborating with international teams to ship robust products.