Backend developer Jobs in Mississauga, ON

We are looking for a Senior Java Backend Engineer with hands-on experience in designing end-to-end data pipelines using Java and Spring Boot, and enterprise API design. You will own end-to-end delivery of enterprise reporting APIs backed by complex data pipelines — from Oracle query design and ETL/ELT workflows to secure Spring Boot services deployed on shared infrastructure. The ideal candidate bridges the gap between application engineering and data platforms.

Responsibilities:

• Conduct tasks related to feasibility studies, time and cost estimates, IT planning, risk technology, applications development, model development, and establish and implement new or revised applications systems and programs to meet specific business needs or user areas
• Monitor and control all phases of development process and analysis, design, construction, testing, and implementation as well as provide user and operational support on applications to business users
• Utilize in-depth specialty knowledge of applications development to analyze complex problems/issues, provide evaluation of business process, system process, and industry standards, and make evaluative judgement
• Recommend and develop security measures in post implementation analysis of business usage to ensure successful system design and functionality
• Consult with users/clients and other technology groups on issues, recommend advanced programming solutions, and install and assist customer exposure systems
• Ensure essential procedures are followed and help define operating standards and processes
• Serve as advisor or coach to new or lower level analysts
• Has the ability to operate with a limited level of direct supervision.
• Can exercise independence of judgement and autonomy.
• Acts as SME to senior stakeholders and /or other team members.
• Appropriately assess risk when business decisions are made, demonstrating particular consideration for the firm's reputation and safeguarding Citigroup, its clients and assets, by driving compliance with applicable laws, rules and regulations, adhering to Policy, applying sound ethical judgment regarding personal behavior, conduct and business practices, and escalating, managing and reporting control issues with transparency.

Skills & Requirements

• Strong in Core Java — collections, generics, streams, lambdas, exception handling, OOPs concepts, and multithreading/concurrency (executors, threads).
• Strong in Spring Boot — Spring Data, Spring Batch, Spring Security.
• Experience with Spring Data JPA/JDBC — repositories, entity mapping, transactions (@Transactional), connection pooling (HikariCP), and lazy/eager loading.
• Hands-on with Spring Security — authentication/authorization, BCrypt, role-based access control, and securing REST endpoints.
• Design, develop, and maintain RESTful APIs using Java and Spring Boot.
• Good understanding of the end-to-end API development lifecycle — from design and contract definition through implementation, testing, deployment, and monitoring.
• Strong understanding and implementation experience of integrating APIs with API gateways such as Apigee and Amazon API Gateway.
• Proficient with Jackson (ObjectMapper config, custom serializers, strict request validation) and OpenAPI/Swagger for API documentation.
• Write and optimize complex Oracle SQL queries (multi-table joins, analytic functions, subqueries, performance tuning).
• Experience with Kafka, MQ, or event-streaming platforms for real-time data ingestion and processing.
• Open to working on data pipelines and building ETL workflows using Java or other programming languages such as Scala as required.
• Work with data warehousing concepts — fact/dimension modeling, slowly changing dimensions, and data quality checks.
• Basic understanding of the Big Data ecosystem is a plus.
• Good to have experience building and optimizing data workflows using tools such as Apache Spark.

Recommended Qualifications:

• 4+ years of relevant experience
• Experience in systems analysis and programming of software applications
• Experience in managing and implementing successful projects
• Working knowledge of consulting/project management techniques/methods
• Ability to work under pressure and manage deadlines or unexpected changes in expectations or requirements

Education:

• Bachelor’s degree/University degree or equivalent experience

This job description provides a high-level review of the types of work performed. Other job-related duties may be assigned as required.

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Job Family Group:

Technology

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Job Family:

Applications Development

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Time Type:

Full time

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Primary Location Full Time Salary Range:

$94, - $141,

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Most Relevant Skills

Please see the requirements listed above.

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Other Relevant Skills

For complementary skills, please see above and/or contact the recruiter.

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Automated Processing and AI

We use automated processing, including artificial intelligence, for our legitimate business interests (or our reasonable and appropriate business purposes) to identify and align the candidate's skills and abilities with a specific job opening. Additionally, if you so choose, or consent, we can match your skills and abilities to other suitable roles at Citi.

Importantly, all our hiring processes and decisions, including determining your suitability for a role, are conducted, checked, and decided by individuals. Our automated processing and AI do not involve relying on automatic or autonomous decision-making. Please refer to any Jurisdictional Considerations, with specific provisions for your country (where relevant) for further details.

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