3Core Systems, Inc. is seeking a highly skilled Software Engineer Level 4 specializing in Java backend development to join their engineering team in Chicago, Illinois. This senior-level position involves architecting, developing, and maintaining robust backend solutions that power mission-critical enterprise applications for clients across various industries. The Software Engineer Level 4 will lead backend development initiatives, collaborate with cross-functional teams to design scalable microservices architecture, and implement high-performance Java applications that meet stringent quality standards. This role requires deep expertise in Java frameworks, database optimization, and cloud-native development practices to deliver innovative solutions that drive business growth. Key responsibilities include designing and developing RESTful APIs and microservices using Java and Spring Boot, implementing secure authentication and authorization mechanisms, optimizing database queries and data models for performance, mentoring junior developers and conducting code reviews, participating in architectural decision-making and technical design sessions, troubleshooting production issues and ensuring system reliability, integrating third-party services and APIs, and maintaining comprehensive documentation for all developed systems. Required qualifications include a bachelor's degree in computer science or related field, minimum of seven years of professional Java development experience, proven expertise in Spring Framework and Hibernate or JPA, strong understanding of SQL and NoSQL databases, experience with RESTful web services and API design, familiarity with version control systems like Git, and excellent problem-solving and communication skills. Essential skills for this position encompass advanced Java programming and object-oriented design patterns, Spring Boot and Spring Cloud frameworks, microservices architecture and containerization with Docker and Kubernetes, relational and NoSQL databases including PostgreSQL and MongoDB, message queuing systems like Apache Kafka or RabbitMQ, cloud platforms such as AWS or Azure, CI/CD pipelines and DevOps practices, unit testing frameworks and test-driven development, and agile methodologies including Scrum or Kanban. 3Core Systems, Inc. is a dynamic technology company committed to delivering innovative software solutions that transform businesses. The company fosters a collaborative work environment where engineers can work on challenging projects using cutting-edge technologies while maintaining work-life balance. The company offers competitive compensation packages including health insurance, retirement plans, and flexible work arrangements. Employees benefit from professional development opportunities, certification reimbursements, and access to the latest development tools and technologies. Career advancement paths include technical leadership roles, architecture positions, and management opportunities. Growth opportunities at 3Core Systems include participation in internal training programs, attendance at industry conferences, mentorship from senior architects, and exposure to diverse project portfolios that enhance technical expertise. The organization encourages innovation and provides resources for employees to experiment with emerging technologies and contribute to open-source initiatives.