Full Stack Developer

Circle K Business Centre is a shared service center supporting Circle K Europe operations in Finance & Control, IT, HR, Transport Fuel, and Customer Service. Circle K is part of Alimentation Couche Tard Inc., operating globally with approximately 12,300 sites across North America, Europe, Asia, and the Middle East. The development teams have implemented various software solutions including web applications and native mobile applications for Circle K customers.

Must have:

• 4+ years of Java development experience (Java 8+, ideally 11+), including JUnit, JPA/Hibernate, JAX-RS/JAX-WS.
• Solid Spring Framework experience including Spring Boot, Data, Cloud, legacy Spring with XML/Java configuration, annotations, and custom extensions.
• Experience with REST and SOAP interfaces, API documentation (Swagger/OpenAPI), and microservice communication patterns.
• Experience with relational databases (PostgreSQL, SQL, data modelling).
• Proficiency in at least one modern JavaScript framework (React, Angular, Vue.js, SAP UI5 or similar) and TypeScript.
• Practical knowledge of Git, CI/CD, and version control workflows (Jenkins, Sonar, Gradle).
• Understanding of POS systems, retail checkout flows, and payment processing concepts.
• Knowledge of design patterns, principles, and basics of Domain Driven Design.
• Experience with agile methodologies (SCRUM).
• Fluent English and Polish (B2/C1 minimum).

Nice to have:

• Experience with OmniPOS / CLOUD4RETAIL platform.
• Knowledge of fiscalisation requirements in European markets.
• Experience with JxBrowser or other Chromium-based embedded browsers.
• Familiarity with Storemanager or similar retail configuration tools.
• Experience in loyalty systems integration, mobile payment flows, or self-checkout solutions.
• Experience with NoSQL (MongoDB, Cosmos DB) and Redis.
• Experience with containerisation and orchestration (Docker, Kubernetes).
• Experience with cloud environments (preferably Azure).
• Knowledge of TDD/BDD approaches (Spock, Mockito, Cucumber).
• Understanding of edge computing architectures.
• Degree in Computer Science or Engineering.

• Design and implement backend services for the global retail sales platform, including domain services, REST/SOAP interfaces, message-driven integrations, and data access layers.
• Design and implement POS functionality using a proprietary Spring-based backend and custom DSL.
• Build and maintain custom extensions, integrations, and configurations within the retail platform.
• Work with Data Containers, Master Data distribution, and Service API for POS integrations.
• Implement and configure business processes such as checkout flows, payment handling, barcode processing rules, and loyalty engine integrations.
• Contribute to localization and fiscalisation of POS solutions for European markets.
• Ensure proper lifecycle management across DEV, TEST, PROD environments.
• Develop custom web applications for POS embedded browser (JxBrowser/Chromium) using the App Enablement Framework and JavaScript API bridge.
• Build backend endpoints and integration flows for these applications.
• Extend and maintain enterprise frontend applications (Employee Hub, Launchpad).
• Adapt solutions for in-store hardware constraints like touch input and limited screen real estate.

When working with us you will not be judged on race, national origin, gender, sexual orientation, disability, age, or other legally protected status. Fluency in English and Polish is required (B2/C1).