Software Engineer, Build Systems / CI

Stack

Responsibilities

• ▹Own and evolve Bazel-based build and test workflows across a large, polyglot monorepo
• ▹Design and maintain Starlark rules, macros, and toolchains that make builds reproducible and hermetic
• ▹Improve CI performance and reliability across Buildkite pipelines: queue time, cache hit rates, test sharding, and flake isolation
• ▹Build systems that reduce unnecessary CI work through affected-target detection, dependency graph analysis, test selection, caching, and smarter scheduling
• ▹Improve local development workflows so engineers can reproduce CI behavior and debug build failures quickly
• ▹Operate and optimize build infrastructure across Docker/OCI images, Kubernetes-based runners, and cloud resources
• ▹Instrument build and CI systems with metrics, logs, traces, and dashboards to measure speed, reliability, cost, and developer impact
• ▹Partner directly with product, infrastructure, and research engineering teams to understand pain points and remove systemic bottlenecks
• ▹Use modern AI tools to rethink CI failure analysis and flaky test debugging
• ▹Participate in an on-call rotation for critical developer infrastructure

Requirements

• ▹5+ years of software engineering experience, including significant experience building infrastructure or tooling for developers
• ▹Hands-on experience with Bazel, Buck, Pants, Gradle, or similar build systems, and understanding of the tradeoffs of hermetic builds, dependency graphs, caching, and sandboxing
• ▹Experience building or operating CI systems at scale, in environments where build time, queue time, and test flakiness materially affect engineering velocity
• ▹Comfort writing production software for internal platforms, involving code, design, debugging, operations, and long-term ownership
• ▹Ability to debug distributed build and CI failures across source control, dependency management, containers, runners, remote caches, and test frameworks
• ▹Deep care for developer experience and empathy for the small sources of friction that slow teams down

Nice to have

• ▹Experience applying AI tools to developer infrastructure
• ▹Proficiency across multiple languages (Python, Go, TypeScript, Rust, C++)
• ▹Experience with Terraform and infrastructure as code
• ▹Experience operating and scaling Kubernetes-based CI runners

Soft skills

About the company

OpenAI is an AI research and deployment company dedicated to ensuring that general-purpose artificial intelligence benefits all of humanity. The company pushes the boundaries of AI capabilities and seeks to safely deploy them to the world through its products.