Our financial services client is seeking a Senior Java Backend Developer (10+ years) to design and develop cloud-native backend solutions on AWS Duration: Until Dec 31st, (high possibility of extension) Location: Downtown Toronto (Hybrid, 2 days a week - Monday and floating day) Hours of Operation: 9 - 5 Role Overview The Java Backend Developer is responsible for designing, developing, and maintaining scalable, secure, and high-performance backend systems.

This role requires deep expertise in Java development and strong experience building cloud-native applications on AWS.

The developer will translate business requirements into robust backend services, ensuring alignment with architectural standards, cloud best practices, and enterprise technology strategy.

Must Have Skills: 8+ years of experience in Java backend development Strong proficiency in Java (core + Spring Boot) Reactive programming using Java Flux / Project Reactor RESTful API design and development Distributed systems and microservices architecture Hands-on AWS experience (ECS, Lambda, ECR, RDS, DynamoDB, IAM) Experience with messaging systems (Kafka, MQ) Experience with SQL and NoSQL databases Cloud-native application design expertise Strong Dev

Ops experience (CI/CD, monitoring, infrastructure as code)



JUnit or similar backend testing frameworks Experience building and scaling large backend systems Core Competencies Robust problem-solving and analytical skills Deep understanding of backend systems, APIs, distributed and reactive architecture Ability to work independently on complex technical challenges Strong collaboration and communication skills Commitment to clean code and engineering excellence Education Bachelors degree in Computer Science, Software Engineering, or a related technical field (or equivalent practical experience).

Responsibilities: Design, develop, and maintain Java-based backend applications and microservices Build and integrate RESTful APIs, messaging systems (Kafka/MQ), and data pipelines Develop cloud-native solutions on AWS, ensuring scalability, reliability, and security Implement best practices in logging, monitoring, performance, and error handling Translate business requirements into technical designs and high-quality code Perform code reviews and ensure adherence to development standards Conduct unit testing and support automated testing frameworks Troubleshoot and resolve production issues, including root-cause analysis Optimize systems for performance, scalability, and maintainability Contribute to architecture design and technology evaluations Collaborate with stakeholders to deliver high-quality solutions Support Dev

Ops practices including CI/CD and deployments Mentor team members and promote backend engineering best practices

📌 Senior Java Backend Developer to design and develop cloud-native backend solutions on AWS (Toronto)
🏢 S.i. Systems
📍 Toronto