Security Engineer Cryptography & Blockchain

Role: Senior Security Engineer, Digital Assets

Location: Southlake, TX ; Austin, TX

Duration: Long term Contract

Responsibilities

Wallet Architecture & Key Management

• Design and implement secure digital wallet solutions across MPC, HSM-based, and hot/warm/cold storage models.
• Establish robust key lifecycle management including generation, storage, rotation, and recovery.
• Implement distributed key generation and signing mechanisms to eliminate single points of failure.
• Define and support custodial and non-custodial control frameworks aligned to security requirements.
• Collaborate with technical stakeholders to validate cryptographic design and architecture decisions.

Cryptography & Blockchain Security Engineering

• Develop and integrate security-critical components using modern cryptographic protocols.
• Apply secure design principles across blockchain and decentralized application environments.
• Work on cross-chain interoperability and blockchain security patterns.
• Evaluate and implement emerging technologies such as Zero Knowledge Proofs (ZKPs), Decentralized Identity (DID), and CBDC-related frameworks.
• Ensure all implementations are secure, auditable, and production-ready.
• Leverage Web3 security tools (Slither, Mythril, fuzz testing frameworks) and code in C, C++, Rust, or Go.

Transaction Controls & Policy Management

• Design and implement programmable transaction control frameworks, including:
• Multi-party approval workflows
• Quorum-based authorization models
• Transaction limits and velocity controls
• Role-based access and segregation of duties
• Translate risk and compliance requirements into deterministic and testable policies.
• Ensure policies are enforceable, observable, and version-controlled.

Security, Risk & Cross-Functional Collaboration

• Partner with engineering, cybersecurity, and risk/compliance teams to ensure strong security posture.
• Proactively identify vulnerabilities, misconfigurations, and operational risks.
• Contribute to threat modeling, security reviews, and architectural assessments.
• Support incident analysis and remediation for blockchain or custody-related issues.
• Engage with external security auditors for validation and assurance activities.

Blockchain Platforms, Tokenization & Smart Contracts

• Evaluate blockchain platforms and protocols for scalability, security, and suitability.
• Design and review tokenization frameworks for assets such as securities and stablecoins.
• Work with token standards including ERC-20, ERC-721, ERC-1155, and related models.
• Assess token lifecycle management, settlement mechanisms, and on-chain governance structures.
• Design and audit cross-chain interoperability solutions (e.g., lock-mint, burn-mint, atomic swaps).

AI-Enabled Engineering & Security Practices

• Utilize GenAI and AI-assisted tools to enhance:
• Threat modeling
• Cryptographic reviews
• Documentation and validation
• Apply AI techniques to improve engineering efficiency while maintaining security and accuracy.

Qualifications

Core Qualifications

• 7+ years of experience in software engineering, with a strong focus on security and cryptographic systems.
• Hands-on expertise in secure wallet technologies and key management solutions (e.g., MPC, HSMs, or equivalent).
• Strong understanding of cryptographic primitives, secure protocol design, and distributed system architectures.
• Experience developing systems where security failures carry significant business or operational risk.
• Proven ability to collaborate effectively across engineering, security, and risk functions.

Preferred Qualifications

• Experience with digital assets, crypto custody platforms, or blockchain infrastructure.
• Exposure to advanced domains such as ZKPs, decentralized identity (DID), DeFi protocols, or CBDC-related systems.
• Experience designing or implementing policy-driven transaction controls in high-risk environments.
• Strong security mindset, with the ability to analyze and reason through complex threat models.
• Familiarity with AI-assisted tools to enhance secure software development practices.