Senior Java Tech Lead — Big Data & Spark Architect

Citigroup Inc.; Mississauga; On-site; CAD 121,000 - 171,000; Full time

Job summary

Citigroup Inc. in Mississauga, Canada is seeking a Senior Java Engineer/Tech Lead to design, develop, and optimize distributed data applications and backend services.

You will build scalable data pipelines with Java, Spark, and Hadoop ecosystem tools, and lead technical design discussions with data engineers and architects. The role requires hands-on expertise in big data technologies, cloud platforms, and performance tuning to deliver enterprise-scale solutions.

Qualifications

• 8+ years of software development experience.
• 5+ years of hands-on Java backend development.
• Expert in Java and Spark development with hands-on experience with Apache Spark and Big Data technologies.
• Strong SQL and data analysis skills.
• Experience delivering enterprise-scale Big Data solutions in cloud environments.
• Ability to lead technical design discussions and mentor team members.

Responsibilities

• Design, develop, and maintain scalable backend applications using Java.
• Build high-performance data processing pipelines using Apache Spark.
• Develop and optimize ETL/ELT workflows for large-scale data platforms.
• Work with Hadoop ecosystem components including Hive, HDFS, YARN, and Spark.
• Design and implement distributed data processing solutions on Databricks.
• Develop batch and real-time data processing applications.
• Optimize Spark jobs for performance, memory management, and scalability.
• Work closely with data architects, data engineers, and business teams.
• Implement data quality, validation, monitoring, and observability solutions.
• Integrate data from multiple sources and platforms.
• Participate in code reviews and architecture discussions.
• Support production deployments and troubleshoot performance issues.
• Ensure security, governance, and compliance requirements are met.

Skills

Java backend

Big Data concepts

Data analysis

Cloud experience

Mentoring / leadership

Education

Bachelor's degree

Master's degree preferred

Tools

Databricks

Apache Spark

Hive

HDFS

YARN

Job description

Citigroup Inc. in Mississauga, Canada is seeking a Senior Java Engineer/Tech Lead to design, develop, and optimize distributed data applications and backend services.

You will build scalable data pipelines with Java, Spark, and Hadoop ecosystem tools, and lead technical design discussions with data engineers and architects. The role requires hands-on expertise in big data technologies, cloud platforms, and performance tuning to deliver enterprise-scale solutions.