Senior Full Stack Developer

Luxoft; Kraków; On-site; PLN 180,000 - 240,000; Full time

Job summary

Luxoft in Kraków is looking for a senior Full-Stack Developer (Java + React) to join our client's team and help build a new AI-enabled application platform for investment banking. You will design, develop and maintain scalable back-end services with Java/Spring and front-end with React/TypeScript, and work with AI-assisted tools to speed delivery while upholding quality.

You'll participate in architecture discussions, mentor teammates, write tests, and contribute to CI/CD and agile ceremonies,

Qualifications

• At least 8 years of professional software development experience.
• Strong hands-on experience with Java (Java 11+) and Spring / Spring Boot.
• Strong hands-on experience with React, TypeScript/JavaScript, HTML and CSS.
• Proven experience delivering full-stack features end to end, from UI to back-end services and the database.
• Hands-on experience with AI coding assistants (e.g., GitHub Copilot).
• Familiarity with CI/CD pipelines and Git workflows.
• Knowledge of generative AI and prompt engineering, incl. integrating LLM APIs.

Responsibilities

• Design, develop and maintain scalable back-end services and APIs using Java (Spring Boot).
• Build responsive front-end applications using React and TypeScript.
• Apply clean code principles and CI/CD pipelines to improve engineering standards.
• Write automated tests (unit, integration, E2E) for front-end and back-end.
• Work in an Agile environment (Scrum/Kanban) with QA and product stakeholders.
• Mentor teammates and contribute to architecture decisions and code reviews.

Skills

Java

Spring Boot

React

TypeScript

REST APIs

AI assistants

CI/CD

Git

Agile

Job description

Project description

We're looking for a senior Full-Stack Developer (Java + React) to join our client's team and help build a new AI-enabled application platform. The team works with modern AI-assisted tools such as GitHub Copilot and generative AI, and cares about clean code, agile methods and high-quality delivery. The client is in the investment banking industry, and the platform supports collateral and margin management.

Responsibilities

• Design, develop and maintain scalable back-end services and APIs using Java (Spring Boot)Build responsive, high-performance front-end applications using React and TypeScriptUse AI-assisted development tools such as GitHub Copilot to speed up delivery while keeping quality and security highDesign and integrate generative AI features into business applications, including prompt engineering, LLM integration and evaluation of model outputsDefine and consume RESTful APIs, and communicate requirements and constraints clearly across teamsAdvise and guide the team on architecture, design decisions and best practices, including the responsible use of AI toolsMentor developers and raise the team's technical level through code reviews and pair programmingTranslate business and product requirements into robust end-to-end technical solutionsApply clean code principles and help improve engineering standards, tooling and CI/CD pipelinesWrite and maintain automated tests (unit, integration, end-to-end) on both front end and back endTake an active part in agile ceremonies (Scrum/Kanban), including refinement, planning, reviews and retrospectivesWork closely with QA, product managers, architects and business stakeholders to deliver high-quality work that fits business needsSupport and improve existing applications in a fast-paced, enterprise investment-banking environment

SKILLS

Must have

• At least 8 years of professional software development experience, including long-term projectsStrong hands-on experience with Java (Java 11+) and Spring / Spring BootStrong hands-on experience with React, TypeScript/JavaScript, HTML and CSSProven experience delivering full-stack features end to end, from UI to back-end services and the databaseHands-on experience with GitHub Copilot or similar AI coding assistants in daily developmentPractical knowledge of generative AI and prompt engineering, including integrating LLM APIs (e.g. OpenAI, Azure OpenAI) into applicationsFamiliarity with CI/CD pipelines and Git-based workflowsClean coding skillsExcellent problem-solving skillsFamiliarity with agile practices (Scrum, Kanban, etc.)Good communication skills and the ability to state requirements clearly to other teams

Nice to have

Experience in automated testing (JUnit, Jest, React Testing Library or similar)Experience in investment banking or capital marketsExposure to RAG architectures, vector databases or AI agent frameworksWorking knowledge of Unix/Linux and shell scripting