Head of Blockchain Security

Bullish•New York, NY

9h•$260,000 - $275,000•Onsite

About The Position

Bullish is looking for an exceptional Head of Blockchain Security to own and elevate the end-to-end security posture of our blockchain infrastructure, custody systems, and smart contract protocols. In this role, you will operate as both a high-impact technical authority and a strategic partner to internal teams, protocol founders, and external security partners. You will design scalable security frameworks, lead complex audits across multi-chain environments, and engineer rapid-response mechanisms to protect assets in high-stakes environments. We operate lean, move fast, and value high emotional intelligence alongside deep technical rigor. This role is based in NYC and will be required to work onsite at our office a minimum of 4 days per week.

Requirements

7+ years in cyber security, with 5+ years dedicated specifically to blockchain and smart contract security
Hands-on experience assessing smart contracts written in Solidity, Rust, and/or Move.
Strong background in C/C++, Linux, and cloud native architectures (AWS, Azure, GCP).
Proven background in senior-level penetration testing, application security, offensive security methodologies, design reviews, and threat modeling (OWASP Top 10, SANS CWE 25).
Deep expertise in applied cryptography (PKI, algorithms, encryption at rest/in transit) and network/protocol fundamentals (IP, DNS, HTTP, SSL/TLS)
Strong working knowledge of institutional custody infrastructure and major DeFi protocols across Ethereum, Solana, Stacks, and Sui.
High EQ & Communication: Ability to articulate critical risks concisely to technical teams and non-technical stakeholders alike.
Outstanding self-management and operational autonomy across global time zones.

Nice To Haves

Offensive security certifications (OSCP, OSWE, OSCE) or related credentials.
Track record of public security research, published vulnerability papers, or presentations at major industry conferences.

Responsibilities

Lead deep-dive architectural reviews and security audits of smart contracts (Solidity, Rust, Move), focusing on protocol-level vulnerabilities.
Oversee external third-party audits for high-complexity releases.
Produce clear, prioritized technical risk reports.
Serve as the primary security advisor to protocol founders, engineering leads, and executive leadership, translating complex risks into actionable decisions.
Build, deploy, and maintain robust blockchain monitoring, alerting, and automated detection systems across major ecosystems.
Design and operate automated emergency exit workflows to protect protocol assets under adverse market or security conditions.
Facilitate cross-industry incident response tabletop exercises.
Conduct rigorous technical assessments of external institutional custody systems, internal treasury controls, and third-party vendor infrastructure.
Build repeatable security frameworks and processes that enable our security program to scale seamlessly alongside aggressive organizational growth.