Senior Engineer (Compute & Agents)

About Buildkite

At Buildkite, our mission is to unblock every developer on the planet. We’ve rethought how software delivery should work and have built a platform that is fast, reliable, secure, and able to scale to the needs of the most demanding high-growth tech companies globally, including Airbnb, Shopify, Canva, PagerDuty, Lyft, and Pinterest.

Job Overview

We’re looking for a Senior Engineer to join our Compute and Agents team. In this role, you’ll help design, build, and scale tools that empower some of the world’s best software engineering teams. You’ll collaborate closely with engineers, designers, and product managers to deliver impactful features and improvements while working on challenges at the intersection of developer experience, scalability, and performance.

This is a highly collaborative, hands-on role where you’ll contribute to product development, influence architectural decisions, and help shape the future of Buildkite’s platform.

About the Team

The Compute and Agents team builds, maintains, and iterates on the infrastructure that keeps Buildkite humming, from our open-source agent trusted by engineers around the world, to our hosted agents and MCP service. It's a team that sits at an exciting intersection: deeply technical infrastructure work on one side, the fast-moving world of AI agents on the other and our own agent sandwiched in the middle.

There's real ownership here. You'll work on problems that matter to developers everywhere, shipping work you can point to and be proud of — alongside a sharp, kind team that loves digging into hard problems together.

What You’ll Do

• Design, build, and ship features that improve developer experience and productivity
• Collaborate with engineers, designers, and product managers to shape solutions that solve customer problems
• Pair program and participate in code reviews, offering and receiving constructive feedback
• Contribute to technical decisions, balancing trade-offs between performance, scalability, and maintainability
• Build and maintain high-quality, well-tested, and maintainable code
• Participate in customer research, discovery sessions, and feedback loops to inform product development
• Help mentor and upskill other engineers within the team
• Stay curious and experiment with emerging tools, patterns, and practices

Skills & Experience We Value

Core Skills:

• Strong communication skills, with empathy and kindness in both written and verbal collaboration
• Proven experience working in distributed engineering teams
• Passion for writing clean, maintainable, and well-tested code
• Ability to analyse technical trade-offs, articulate solutions clearly, and build team consensus
• Comfortable working directly with customers and incorporating feedback into product development
• Familiarity with CI/CD systems, developer tooling, and DevOps concepts

Technical stack

• Go — our primary language, used across our agents and infrastructure. Strong experience or a genuine eagerness to go deep is a must.
• Kubernetes & AWS — we run cloud-native infrastructure at scale. Experience with container orchestration and distributed systems is a big plus.
• Terraform — we manage our infrastructure as code with Terraform. Familiarity with IaC principles and writing reusable, maintainable Terraform is valued.
• Ruby on Rails — the backbone of the Buildkite platform. The majority of our product is built here, so comfort with Rails or a willingness to pick it up matters.
• React & GraphQL — our frontend and API layer, used across the platform alongside Rails.
• PostgreSQL —  Experience with query optimisation, schema design, or managing relational databases under load is a plus.

️ A Typical Day Might Include

• Shaping and pitching new features or experiments
• Reviewing pull requests and shari