[Hiring] Senior Crypto Security Engineer @Lightspark

Role Description

We are seeking a Senior Security Engineer with a rare combination of deep infrastructure roots, application security expertise, and a sophisticated understanding of blockchain protocols. In this role, you will be architecting the safety of a high-throughput, decentralized payment network. Your expertise spans the entire security spectrum:

• Operational rigor to secure mission-critical infrastructure
• Technical depth to audit low-level code
• Intuitive grasp of on-chain anomalies and decentralized threat vectors

WHAT YOU’LL BE DOING:

• Secure Protocol Engineering: Perform deep-dive code audits and risk assessments of core protocol implementations and payment channel logic to prevent funds loss or state corruption by identifying edge cases in distributed systems.
• Hardened Infrastructure: Architect and secure our cloud-native footprint (AWS/GCP), ensuring that validator nodes, signing services, and P2P networking are resilient against both traditional DDoS and protocol-specific eclipse attacks.
• Application & Lifecycle Security: Build and maintain the Secure SDLC for our products, including automated security analysis (SAST/DAST) in CI/CD, managing high-stakes bug bounties, and performing manual penetration tests on our financial APIs.
• Cryptographic Operations: Design and manage mission-critical Key Management Systems (KMS), leading the implementation of Multi-Party Computation (MPC), Threshold Signatures (TSS), and HSM integrations to secure private keys at scale.
• Detection & Response: Develop specialized monitoring for both Cyber threats (unauthorized access, lateral movement) and On-chain threats (channel jamming, fee-siphoning, or routing anomalies).
• Security Expert: Serve as the subject matter expert for engineering teams, bridging the gap between standard web security and crypto-native security.

Qualifications

• 6+ years in Security Engineering with a proven track record that spans Infrastructure, Application Security, and Blockchain/DeFi.
• Hands-on experience with cryptographic primitives (Elliptic Curve, Schnorr, Merkle Trees) and a fundamental understanding of Layer 2 scaling (Lightning Network).
• High proficiency in Python, Rust, or Go, capable of auditing systems-level code for memory safety, race conditions, and cryptographic flaws.
• A history of identifying vulnerabilities in decentralized protocols or high-scale distributed systems.
• Understanding of how to apply traditional frameworks (NIST, OWASP) to the non-traditional world of decentralized finance and self-custody.
• A CS degree is ideal, but contributions to open-source security tools or a history of disclosed vulnerabilities in the crypto space are also valued.
• Ability to translate complex cryptographic risks into actionable engineering requirements for non-security peers.

Benefits

• Inclusive and diverse workplace
• Commitment to reflecting the customers we serve