Senior Backend Engineer: Java, AWS & Event-Driven Systems

Apex Systems; Mississauga; On-site; CAD 120,000 - 130,000; Full time

Job summary

Purolator, Canada’s leading freight, package and logistics provider, is seeking a backend-focused engineer to design and maintain the back-end services powering our high-volume tracking platform. The role emphasizes server-side depth and end-to-end ownership of services.

You'll design and implement backend services in Java, work with AWS, CI/CD, PostgreSQL, and ensure test coverage and robust design. The position is full-time, office-based, reporting to Lead Technology Developer, with a

Qualifications

• Strong hands-on Java backend experience designing non-trivial services.
• Experience with automated testing frameworks (JUnit) and test data / integration testing.
• Solid grasp of software design patterns and OO design.
• Strong SQL ability with PostgreSQL including schema design and query tuning.
• Experience designing event-driven systems (message queues, streams).
• Working knowledge of AWS and CI/CD workflows.
• Ability to reason about performance, concurrency, and failure in high-volume systems.

Responsibilities

• Design and build backend services in Java with clean architecture.
• Build event-driven services and messaging/streaming flows.
• Write and maintain automated tests as a core part of work.
• Apply established design patterns appropriately.
• Work with AWS-hosted infrastructure and CI/CD pipelines.
• Model and tune data in PostgreSQL with SQL.
• Collaborate on API design and contracts with other teams.
• Support and operate services by investigating production issues and incidents.

Skills

Java backend

Automated testing (JUnit)

Software design patterns

PostgreSQL

Event-driven architecture

AWS

CI/CD

Performance & concurrency

Frontend exposure

Education

Bachelor's degree in computer science or equivalent

Tools

JUnit

PostgreSQL

AWS

Job description

Purolator, Canada’s leading freight, package and logistics provider, is seeking a backend-focused engineer to design and maintain the back-end services powering our high-volume tracking platform. The role emphasizes server-side depth and end-to-end ownership of services.

You'll design and implement backend services in Java, work with AWS, CI/CD, PostgreSQL, and ensure test coverage and robust design. The position is full-time, office-based, reporting to Lead Technology Developer, with a