Senior Software Engineer - Karpenter

Why Cast AI?

Cast AI is the leading Application Performance Automation (APA) platform, enabling customers to cut cloud costs, improve performance, and boost productivity – automatically.

Built originally for Kubernetes, Cast AI goes beyond cost and observability by delivering real-time, autonomous optimization across any cloud environment. The platform continuously analyzes workloads, rightsizes resources, and rebalances clusters without manual intervention, ensuring applications run faster, more reliably, and more efficiently.

Headquartered in Miami, Florida, Cast AI has employees in more than 32 countries worldwide and supports some of the world’s most innovative teams running their applications on all major cloud, hybrid, and on-premises environments. Over 2,100 companies already rely on Cast - from BMW and Akamai to Hugging Face and NielsenIQ.

What’s next? Backed by our $108M Series C, we’re doubling down on making APA the new standard for DevOps and MLOps, and everything in between.

About the role

The Karpenter team powers the integration between Karpenter and Cast AI, bringing enterprise capabilities to the most popular open source Kubernetes autoscaler. We enhance Karpenter with advanced features that improve application reliability and performance while optimizing costs. By joining the team, you’ll bridge open source innovation with enterprise requirements, directly impacting how organizations run Karpenter at scale.

Requirements:

• Strong software engineering skills with experience in distributed systems and backend development (ideally GoLang, but not a hard requirement as long as you’re willing to transition to it)
• Strong debugging, optimization, and performance-tuning skills
• Deep understanding of cloud platforms: hands-on experience with cloud platforms like AWS, Google Cloud Platform (GCP), Microsoft Azure, and tools such as Kubernetes for containerization and orchestration
• CI/CD and DevOps practices experience
• Strong English skills, both verbal and written
• Ability to work independently and collaboratively within a team
• Startup mindset: adaptable, proactive, and comfortable with ambiguity
• A proactive, problem-solving mindset with a “yes we can” attitude.
  
  

Nice To Have

• Contributions to the Kubernetes or cloud native OSS ecosystem.
• Experience working with Karpenter
  
  

Responsibilities:

• Design, build, and operate backend services and Kubernetes operators in Go that manage clusters together with Karpenter.
• Participate in architecture and design decisions.
• Contribute to high‑volume data‑plane services (gRPC/REST) and asynchronous workflows.
• Shape public and internal APIs with an eye for simplicity and developer experience.
• Participate in design reviews, code reviews, on‑call rotations, and occasional customer deep‑dives.
  
  

What’s in it for you?

• Competitive salary (€6,500 - €9,000 gross, depending on the level of experience)
• Enjoy a flexible, remote-first global environment.
• Collaborate with a global team of cloud experts and innovators, passionate about pushing the boundaries of Kubernetes technology.
• Equity options.
• Get quick feedback with a fast-paced workflow. Most feature projects are completed in 1 to 4 weeks.
• Spend 10% of your work time on personal projects or self-improvement.
• Learning budget for professional and personal development - including access to international conferences and courses that elevate your skills.
• Annual hackathon to spark new ideas and strengthen team bonds.
• Team-building budget and company events to connect with your colleagues.
• Equipment budget to ensure you have everything you need.
• Extra days off to help maintain a healthy work-life balance.