Senior Security Engineer - Digital Assets

Purple Drive

Senior Security Engineer, Digital Assets

Locations:
Southlake, TX;
Austin, TX

Role Summary

Design, build, and secure institutional-grade digital asset custody platforms. The posting frames this as a hands-on engineering role focused on crypto-native security capabilities and digital asset development, including secure wallet technologies, key management, cryptographic protocols, smart contract security, tokenization, custody policy enforcement, and advanced blockchain security solutions.

Key Responsibilities

• Contribute to the design and implementation of secure wallet solutions spanning MPC, HSMs, cold, warm, and hot wallet architectures, and custodial versus non-custodial control models.
• Implement distributed key generation and signing workflows and ensure secure handling of key lifecycle events such as generation, storage, usage, rotation, and recovery.
• Design and implement security-critical components using modern cryptographic protocols, DeFi application security principles, and cross-chain and blockchain interoperability patterns.
• Evaluate and integrate advanced technologies such as zero-knowledge proofs, decentralized identity frameworks, and applicable CBDC architectures.
• Build and configure programmable custody policy engines with multi-approval workflows, spending thresholds, velocity limits, role-based access controls, and segregation of duties.
• Work with engineering, cybersecurity, risk, compliance, and audit stakeholders on security reviews, threat modeling, architecture assessments, and incident analysis and remediation.
• Assess blockchain architectures, smart-contract frameworks, tokenization approaches, and secure bridge or interoperability models for enterprise suitability.
• Leverage GenAI and agentic AI tools to accelerate threat modeling, cryptographic design reviews, documentation, and validation.

Source-Supported Qualification Themes

• 7+ years of software engineering experience with a strong focus on security or cryptography.
• Hands-on experience with secure wallet technologies and key management systems such as MPC, HSMs, or equivalent.
• Strong understanding of cryptographic primitives, secure protocol design, and distributed systems.
• Experience building systems where security failures have material impact.
• Ability to collaborate effectively across engineering, security, and risk teams.
• Strongly preferred: experience with crypto custody platforms, digital assets, or blockchain infrastructure; hands-on work with ZKPs, DID frameworks, DeFi protocols, or CBDC-related systems; and experience implementing policy-driven transaction controls in high-risk systems.