Senior Full Stack Engineer (Java & React)
StoneX Group Inc.2 years ago
Kraków, PolandSenior
Responsibilities
- Define and evolve multi-year technical strategy and architecture standards across React/Vite, Node.js/Fastify, and Java Spring Boot platforms.
- Resolve complex cross-system design and performance challenges as a final technical escalation point.
- Establish engineering-wide standards for architecture, security, scalability, and reliability.
- Mentor Staff and Senior Engineers and help shape technical career ladders and promotion criteria.
- Align technical roadmaps with business strategy alongside senior engineering, architecture, and product leaders.
- Evaluate emerging technologies and lead organization-wide proofs of concept and build-versus-buy decisions.
- Address systemic platform-level reliability, scalability, and security risks.
- Champion technical documentation, engineering culture, and cross-team knowledge sharing.
- Represent engineering in decisions involving vendors, regulators, and enterprise architecture boards.
Requirements
- Mastery of JavaScript/TypeScript, HTML5, CSS3, large-scale frontend architecture, and microfrontends.
- Deep enterprise-scale expertise with React.js, Node.js, Fastify or Express, and Java Spring Boot.
- Demonstrated experience setting technical direction across multiple engineering organizations or business units.
- Deep expertise in Azure App Services, Azure Functions, Azure DevOps, and enterprise cloud architecture.
- Expert understanding of distributed systems, RESTful API design, and enterprise integration patterns.
- Experience mentoring Staff-level engineers and influencing organization-wide career frameworks.
- Advanced database expertise, including PostgreSQL and MS SQL Server, with experience making large-scale data architecture decisions.
- Experience advising VP- and C-level stakeholders on technical strategy.
- Experience using GitHub Copilot with modern models such as Claude Opus or Sonnet and shaping AI-assisted engineering practices.
- University qualification in Computer Science, Software Engineering, or a similar discipline, or a strong GitHub portfolio demonstrating recent projects.
Benefits
- Permanent, full-time position.
- Hybrid working arrangement with four days in the office and private employee parking.
- B2B contract for 12 months.
Tech Stack
Apache KafkaAzureExpressgRPCJavaJavaScriptMicrosoft SQL ServerNode.jsPostgreSQLReactSpring BootTypeScript
Categories
About StoneX Group Inc.
StoneX Group Inc. is a public financial services firm that connects institutional, commercial, and retail clients to global markets through brokerage, execution, clearing, risk management, and cross-border payments. It offers trading and hedging across commodities, equities, fixed income, futures/options, and FX, and operates retail platforms via GAIN Capital’s FOREX.com and City Index (acquired 2020). Founded in 1924 and headquartered in New York, it lists on Nasdaq under SNEX.