Senior Backend Engineer - Java/AWS

About the Opportunity: ZipStaff is hiring a Senior Backend Engineer for our client, a national passenger transportation organization, to build and support the cloud-native integrations and transaction-processing services behind critical operational systems. You will take hands-on ownership of resilient, multi-region AWS architectures, event-driven pipelines and automated CI/CD workflows, ensuring high reliability, rapid disaster recovery and seamless B2B data exchange.

What You'll Do: Design, build, deploy and maintain scalable microservices, RESTful APIs and event-driven architectures using Java 17+, Spring Boot, Python and AWS integration services. Architect fault-tolerant, high-availability solutions across multiple AWS Availability Zones and Regions, including failover testing and reducing MTTR. Investigate complex production incidents, perform root cause analysis and implement observability with Amazon CloudWatch. Build and optimize CI/CD pipelines using GitHub Actions, Jenkins, AWS CodePipeline and CloudFormation infrastructure-as-code. Implement relational data models, write complex queries and tune performance on Amazon Aurora PostgreSQL. Drive peer code reviews, champion automated testing standards (JUnit, Mockito) and mentor junior developers.

Required Qualifications: 7+ years of professional backend software engineering experience on distributed, high-availability production systems. Advanced hands-on proficiency in Java 17+, Spring Boot and Python. Extensive experience with AWS services including ECS/Fargate, EventBridge, SQS, SNS, Lambda, S3 and CloudWatch. Strong PostgreSQL / Amazon Aurora PostgreSQL skills, including schema design, query optimization and tuning. Experience managing automated deployments with Jenkins, GitHub Actions, AWS CodePipeline and CloudFormation. Proficiency with automated unit and integration testing frameworks (JUnit, Mockito). Bachelor's degree in Computer Science, Engineering or a related field, or equivalent experience. Ability to work on-site in Washington, DC.Preferred Qualifications: Active AWS certification (Solutions Architect, Developer Associate or Cloud Practitioner). Experience with EDI, B2B messaging integrations or high-volume transportation/logistics systems. Based within or easily accessible to the Northeast Corridor for periodic on-site planning sessions.

Benefits: Health Insurance. Dental Insurance. Vision Insurance. 401(k) + 401(k) matching. Paid time off. Referral Program. About ZipStaff: ZipStaff connects skilled technology professionals with leading organizations across the United States, matching top talent with impactful contract and full-time opportunities. To apply, submit your resume through this posting. Qualified candidates will be contacted by a ZipStaff recruiter.