Cryptography & Platform Security SWE

eBay•San Jose, CA

7d•$172,000 - $229,600•Hybrid

About The Position

This role is with eBay’s Cloud Security Engineering team, which builds foundational security services to protect eBay's global marketplace. The team develops and operates secure, scalable cryptographic platforms that enable trusted transactions, secure communications, and strong identity guarantees across millions of users and services. As a Senior Software Engineer – Cryptography & Platform Security, you will build and implement high-assurance cryptographic services that underpin authentication, digital signatures, key management, and secure data protection across eBay’s distributed systems. You will collaborate closely with platform and infrastructure teams to embed robust cryptographic protections into our services and help shape eBay’s long-term security posture.

Requirements

Bachelor’s degree, Master’s degree, or equivalent experience in Computer Science, Engineering, or a related field is required.
Typically, 7+ years of software engineering experience with a focus on security and cryptography is needed.
Proven hands-on experience with cryptographic algorithms and protocols, including RSA, ECC, DSA, and digital signatures, applied in production systems.
Strong understanding of public key infrastructure (PKI), certificate management, and trust models in large-scale, distributed environments.
Proficiency in Java, including experience using JCA/JCE or building secure J2EE-based applications that integrate cryptographic services.
Experience implementing or integrating with key management standards and interfaces such as PKCS#11, KMIP, or similar protocols, and familiarity with secure coding practices and common cryptographic pitfalls.
Ability to work from our San Jose office (in a hybrid or onsite model as defined by eBay policy) and to collaborate optimally across security, platform, and infrastructure teams in a fast-paced environment.

Responsibilities

Design and deliver cryptographic services and libraries that enable secure encryption, digital signatures, and key management for high-scale, global platforms.
Build and evolve systems using public key cryptography (such as RSA, ECC, and DSA) to support secure transactions, identity, and communications across distributed services.
Develop and improve PKI infrastructure, including certificate lifecycle management and trust frameworks, to strengthen authentication and service-to-service trust.
Integrate cryptographic capabilities into Java-based services using JCA/JCE and hardware-backed security modules (for example PKCS#11, KMIP, TPM 2.0) to protect sensitive data and keys.
Lead and participate in threat modeling, security reviews, and cryptographic design validation to proactively identify and mitigate risks.
Improve the performance, scalability, and resilience of cryptographic operations in high-throughput environments while knowing the latest modern standards, vulnerabilities, and approaches.