Software Engineer, Infrastructure Security, Consumer Devices

We are hiring a Security Software Engineer to design and implement the hardware-backed security foundations used across OpenAI’s device ecosystem. A central focus of this role is hardening the boundary between our policy systems and the HSMs that protect sensitive cryptographic keys. This boundary determines which operations may be performed, what may be signed, which policies must be satisfied, and how changes to trusted software and policy are authorized. You will develop security-critical software and firmware within, or immediately adjacent to, an HSM trust boundary. Depending on your background, this may include HSM trusted applications, firmware services, cryptographic mechanisms, device drivers, PKCS#11 components, secure-provisioning protocols, or signing-policy enforcement systems. This is a hands-on software-engineering role. You will be expected to design systems, write and review production code, debug across hardware and software boundaries, and carry projects from initial requirements through deployment. It is not an HSM administration, PKI operations, compliance, or architecture-only position. In This Role, You Will Design and implement security-critical software and firmware for HSMs, secure elements, trusted execution environments, and hardware roots of trust. Build and harden the policy-to-HSM boundary responsible for authorizing certificate issuance and cryptographic signing operations. Develop HSM trusted applications, firmware components, host interfaces, device drivers, SDKs, or cryptographic service integrations. Implement or extend cryptographic interfaces such as PKCS#11, OpenSSL providers or engines, platform key-storage APIs, or comparable hardware-security interfaces. Build firmware and software that cryptographically enforces key generation, provisioning, usage, rotation, recovery, and destruction policies. Design and implement HSM-backed certificate authority, code-signing, key-management, and device-identity systems. Develop end-to-end cryptographic protocols spanning devices, secure hardware, policy services, and backend infrastructure. Build security capabilities supporting device attestation, secure boot, factory provisioning and restoration, user registration, and authentication. Design controls that make trusted software and policy changes verifiable, auditable, and subject to appropriate multi-party authorization. Write, review, test, and audit secure embedded software for resource-constrained environments. Develop test harnesses, emulators, fuzzers, and fault-injection tooling to validate security properties and failure behavior. Threat-model hardware and software trust boundaries and translate findings into concrete engineering improvements. Partner with hardware, firmware, infrastructure, application, and security teams to integrate secure-by-default capabilities into production systems. Help establish engineering standards for HSM development, applied cryptography, secure key management, and certificate infrastructure. You Might Thrive in This Role If You Have A strong track record of designing, implementing, debugging, and shipping production systems software. Deep programming experience in C, C++, or Rust. Hands-on experience developing security-critical software or firmware within, or directly adjacent to, an HSM, secure element, TEE, or hardware root of trust. Experience developing one or more of the following: HSM firmware or trusted applications Cryptographic mechanisms or hardware-accelerated cryptographic services HSM device drivers, host libraries, SDKs, or middleware PKCS#11 providers, mechanisms, or integrations Secure key-provisioning or key-injection protocols HSM-backed certificate authority or code-signing systems Signing-policy enforcement within a hardware-backed trust boundary Experience building secure embedded firmware for constrained environments. Strong knowledge of applied cryptography, digital signatures, key hierarchies, secure key management, and