Staff Software Engineer, Chainguard Harness

Chainguard is the trusted source for open source. By delivering hardened, secure, and production-ready builds of all the open source software engineers and AI agents rely on, Chainguard helps organizations build faster, stay compliant, and eliminate risk. Our customers include Fortune 500 enterprises and global industry leaders, including Anduril, Canva, Fortinet, Hewlett Packard Enterprise, OpenAI, Snap Inc., and Snowflake. Chainguard is venture-backed by leading investors, including Amplify, IVP, Kleiner Perkins, Lightspeed Venture Partners, Mantis VC, Redpoint Ventures, Sequoia Capital, and Spark Capital. The role, in a nutshell At Chainguard we're focused on securing the software supply chain, and we're building the next generation of products at the intersection of security and AI. You'll join a small, fast-moving team building Chainguard Harness. Chainguard Harness uses frontier AI models to hunt down exploitable vulnerabilities in a customer's application, then delivers validated findings with recommended fixes, with no model access required. Customers trust us with their source code, so security isn't just a feature of this product. It is the product. As a Staff engineer you'll own large parts of the Harness architecture, guide technical decisions across the team, and help take the product from beta to a service that scales to many more customers and environments. What you'll do • Own major parts of the system end to end, from design through implementation, rollout, and operation • Build security into the foundation: protecting customer code end to end, least-privilege access, and auditing everything the system and its operators do. Partner with Product and Security on threat models and reviews. • Make Harness a reliable, observable, production-grade service, making sound long-term tradeoffs around scale, cost, technical debt, and build versus buy. • Work directly with customers, Product, and our field team. You'll join customer calls and turn feedback into the roadmap. • Raise the bar for the team through design docs, code review, and mentoring, and by showing how AI tooling can make a small team move fast without cutting corners on security. What we're looking for • 10+ years of experience in software development • A track record of building and operating production services where security and data confidentiality were hard requirements, not afterthoughts • Experience designing systems that hold confidential customer data end to end • Experience shipping software into air-gapped, disconnected, or highly restricted environments • Deep experience with cloud infrastructure on GCP and/or AWS, including IAM, KMS, networking, and infrastructure as code (Terraform) • Hands-on experience with virtualization and workload isolation, such as KVM, QEMU, Firecracker or Cloud Hypervisor, gVisor, nested virtualization, or bare-metal hosts • A working knowledge of applied cryptography: envelope encryption, key management and rotation, HSM/KMS-backed keys, and signing • Proficiency with Go • Experience with AI tooling and a genuine enthusiasm for applying it to hard problems; experience building agentic systems is a plus • Strong communication skills and proficiency in English. You can explain a security model to an engineer, a security reviewer, and a customer's CISO, and you work autonomously, take initiative, and ask for help early. Nice to have • A background in offensive security, vulnerability research, penetration testing, or application security, and a sense of what separates a real, exploitable finding from noise • Experience building and running arbitrary third-party code across many languages and build systems • Familiarity with vulnerability data and disclosure: CVE and OSV formats, triage and dedup