Senior Software Engineer

About Upsun (formerly Platform.sh) 

Upsun is the cloud application platform humans and robots love. It is built for today’s hybrid teams, where AI agents write and test code and humans focus on solving the problems that really matter. Developers, DevOps engineers, and platform teams use Upsun to build, ship, and scale confidently without wrestling with backend infrastructure. We give you your time back. You get:

• Predictable performance, even at scale


• Secure, compliant environments by default 


• Real-time observability and profiling built in


• Cloning, configuration, and provisioning in seconds 


• AI-ready features that plug directly into your stack

The name says it all. "Up" means uptime, reliability, and acceleration. "Sun" reflects our follow-the-sun-support, a 24x7, globally distributed support team keeping the lights on while you rest. Our core belief is that software should power brighter solutions and greater innovation.

Upsunners are a remote, global workforce, and we thrive in a multicultural team. We are committed to open source and an open, welcoming environment. Our team spans the globe and the experience spectrum.

What's our commonality, our cultural fabric? A curious spirit and a thirst for knowledge; an eagerness for innovative ideas and cultures. We believe we can build anything together in an environment that frees you to do your best work.

Our values: 

We make a positive impact.

✨ We aim for the stars.

We care for each other. 

Impact of a Senior Software Engineer

As a Senior Software Engineer at Upsun, you are part of the core engineering team building and maintaining the low-level orchestration components that power our cloud platform. You directly impact the reliability, scalability, and efficiency of the environment for customers running complex applications. You balance day-to-day maintenance of our stable, pre-established systems with the strategic execution of modernizing our base orchestration layer from Python to Go.

Your work enables seamless cross-functional operations across our global infrastructure, solving highly complex challenges involving asynchronous networking, distributed coordination, and performance-critical systems.

This role reports to the Director, Software Engineering.

What to expect

• Core Projects: Work on improving and maintaining our orchestration engine and git interface, ensuring they meet high standards of performance, reliability, and security.


• Daily Tasks: Work on product or internal features (like reducing dependencies or improving our internal telemetry), extending our testing suite, or releasing our components.


• Team Collaboration: Work closely with product, security, and infrastructure teams on container orchestration solutions that align with company goals and customer needs.


• Challenging Problems: Build backwards compatible solutions to complex problems while optimizing services to run efficiently and troubleshooting when deployments fail.


• Drive Innovation: Constantly seek opportunities to improve automation, testing, and deployment processes.

What you bring

• Strong software engineering background with proficiency in Python and Go.  


• Comfort working on low-level systems. 


• Proficiency in asynchronous programming and concurrency models in Python or similar languages.


• Strong expertise in Linux systems and internals, including process management, networking, containers, and file systems.


• Production experience with containerization technologies (Docker, OCI images, LXC etc.).


• In depth knowledge of Git protocol including how repositories work.


• Comfort with debugging complex systems, including going through traces and logs.


• Pragmatic problem-solving, employing practical solutions to overcome complex problems efficiently.


• Hands-on experience with AI coding assistants and LLM APIs, including applying them to code review, documentation, and debugging.


• Excellent communication skills, with the ability to engage in discussions, accept feedback, and share knowledge with diverse audiences.

Bonus Points

• Knowledge of orchestration platforms such as Kubernetes (K8s). 


• Experience with GitLab CI/CD pipelines.


• Experience working in PaaS or cloud-based environments.


• Experience with  high availability architectures and fault tolerance.

Where we hire

At Upsun, remote work isn't just a trend - it's our foundation. The freedom of remote work with the support of a diverse, global team has been our successful model for over a decade. Our culture celebrates flexibility and collaboration, and while we have team members in over 30 countries around the globe, we are currently focused on hiring for this role in Canada. Although we’re unable to provide visa sponsorship at this time, we welcome applications from all qualified candidates who are legally authorized to work in these countries. 

How we hire

We know that a great hire won’t meet every requirement that we’ve outlined. If you can see yourself elevating the team, we want to hear your story. Few of us would be here had we not taken a chance.

You can expect 4 interviews on Google Meet to follow the order below. Should you successfully move through the entire process you will have the opportunity to meet with a variety of Upsunners. Our goal is to ensure you can make the most informed decision on whether this role, and our culture aligns with what you’re looking for in your future working environment. 

1. 45 Minutes with Talent Acquisition 


2. 60 Minutes with Hiring Manager, Director, Software Engineering


3. 60 Minutes with Team (ICs)


4. 45 Minutes with Executive (VP, Software Engineering)

All roles require background checks.

What we offer

A product you can believe in - Join us in transforming how businesses build and manage web applications, driven making a positive impact as a proud B Corp .

An Award-Winning Workplace - We’ve been recognized by Forbes’ Top 30 Companies for Remote Jobs and France’s Best Workplaces for Women.

️ A culture that values your voice - Join a flexible, open, and inclusive work environment where your voice is encouraged, and your ideas shape our growth and evolution.

A global team - Collaborate with colleagues from diverse backgrounds across the world, embracing different perspectives

Benefits and perks - Make the most of what matters to you

Flexible PTO

Comprehensive healthcare coverage (UK, Canada, France, Spain, USA)

Company stock options

Professional development budget

Office equipment budget

‍♀️ Wellness budget

Annual team gatherings

Internet reimbursement

Inclusive parental leave

✈️ Remote work travel program

You belong here

At Upsun, we celebrate diversity in all its forms and are committed to fostering an inclusive, equitable, and supportive workplace where everyone can thrive. We embrace and value different perspectives, backgrounds, and experiences, because they make us stronger as a team. Whoever you are, wherever you're from, and whatever path you've taken, you are welcome here. We encourage you to bring your whole self to work, connect with others, and share your passion. If you need accommodations at any stage of our hiring process, please let us know. We're here to ensure an accessible and comfortable experience for you.