ZipStaff Inc.

Senior Backend Engineer – Java/AWS

Washington, District of Columbia•Contract
$43 - $45 hourly
About the Job
Job Title: Senior Backend Engineer – Java / AWS
Location: Washington, DC (On-site)
Employment Type: W2 Contract

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.