Software Developer - Sr.

Are you a Senior Software Developer who loves solving complex problems, modernizing legacy technology and finding smarter ways to build?

We’re looking for 4 Senior Software Developers to join a high-performing technology team working on exciting application modernization, cloud migration and AI-enabled development initiatives.

This is an opportunity to work hands-on with Java, Spring Boot, Python, AWS, GCP and AI coding tools such as GitHub Copilot while helping transform and modernize established applications.

If you’re the kind of developer who doesn't just write code—you understand it, challenge it, improve it and take ownership of the outcome—we want to hear from you.





Advantages
Prime Location: Work out of the North York office - near vibrant transit, food, and culture spots.

We're especially interested in developers who demonstrate initiative and ownership.

Your resume will stand out if you can show examples of:

Projects you've built independently.
A GitHub portfolio or personal technology projects.
Problems you've identified and solved without being asked.
Process or technical improvements you've initiated.
Taking ownership of a project from concept through production.
Optimizing applications or improving performance.
A genuine passion for technology outside of your day-to-day responsibilities.

We want to see what YOU have built—not just what your employer asked you to build.

Responsibilities
What You'll Be Doing

You’ll be working on a variety of modernization and migration initiatives, including:

Developing and maintaining applications using Java and Spring Boot.
Working with Python-based components, including models and scorecards.
Refactoring and restructuring complex legacy Java code.
Supporting Java-to-Java application migrations.
Untangling legacy code and transforming it into clean, maintainable and production-ready solutions.
Working across AWS and GCP cloud environments.
Troubleshooting applications and services using cloud consoles, logs and monitoring tools.
Using AI coding assistants such as GitHub Copilot to accelerate development.
Reviewing and validating AI-generated code to ensure it meets technical, business and production requirements.
Writing and testing high-quality, reliable code.
Taking ownership of solutions from development through production.

You’ll also have access to experienced team members with 10+ years of knowledge of the existing legacy environment, giving you the support and business context needed to navigate complex systems.

Qualifications
Must-Have

Senior-level Java development experience
Strong Spring Boot experience
Strong Python fundamentals
Experience working with legacy codebases
Experience with application modernization, migration or refactoring
Strong understanding of software development fundamentals
Strong testing and code-validation practices
Experience using AI-assisted development tools, particularly GitHub Copilot or similar
Ability to critically review, understand and improve AI-generated code
Ability to produce clean, readable, maintainable and production-ready code

Nice to Have

Experience with:
AWS
Amazon S3
CloudWatch and log analysis
Google Cloud Platform (GCP)
GKE
GCP logging and monitoring
Cloud infrastructure migrations
Java-to-Java migration/refactoring initiatives

AI Isn't Just a Buzzword Here

AI is becoming an important part of how this team develops software.

We're looking for developers who know how to work with AI—not simply rely on it.

You should be comfortable using tools such as Copilot to accelerate development while having the technical depth to ask:

"Is this code actually right?"

You’ll need to understand the output AI produces, identify potential issues, apply business context and make sure the final solution is secure, maintainable, tested and production-ready.

Strong coding fundamentals are just as important as AI experience.


Summary
If you thrive on solving complex technical challenges in a hybrid work environment, we want to hear from you!

Randstad Canada is committed to fostering a workforce reflective of all peoples of Canada. As a result, we are committed to developing and implementing strategies to increase the equity, diversity and inclusion within the workplace by examining our internal policies, practices, and systems throughout the entire lifecycle of our workforce, including its recruitment, retention and advancement for all employees. In addition to our deep commitment to respecting human rights, we are dedicated to positive actions to affect change to ensure everyone has full participation in the workforce free from any barriers, systemic or otherwise, especially equity-seeking groups who are usually underrepresented in Canada's workforce, including those who identify as women or non-binary/gender non-conforming; Indigenous or Aboriginal Peoples; persons with disabilities (visible or invisible) and; members of visible minorities, racialized groups and the LGBTQ2+ community.

Randstad Canada is committed to creating and maintaining an inclusive and accessible workplace for all its candidates and employees by supporting their accessibility and accommodation needs throughout the employment lifecycle. We ask that all job applications please identify any accommodation requirements by sending an email to accessibility@randstad.ca to ensure their ability to fully participate in the interview process.

This posting is for existing and upcoming vacancies.