Senior Engineer, Custody Engineering (Rust, Tokenization)

Reports to:

Engineering Organization & Culture

At Bullish, we are engineering the institutional standard for the digital asset industry. Our mission is to build a platform where security and compliance are the foundational core, requiring a commitment to technical excellence that goes beyond simply delivering code. We operate as a global engineering organization, setting a high bar in a demanding environment for those driven to do the best work of their careers alongside world-class peers.

We value engineers who treat development as a craft and own the outcome from concept to deployment. You will be expected to navigate the unknown, bring structure to ambiguity, and help shape the frameworks and processes that drive our global teams forward. We refuse to compromise on quality and seek problem solvers who thrive on high-impact technical challenges.

The Team: Custody Engineering

The Custody Engineering Team builds the critical systems that safeguard user assets, architecting secure and compliant infrastructure for the entire lifecycle of funds. Our technical scope is broad, spanning blockchain development, smart contracts, oracles, and the full-stack systems that power them. We operate with a high degree of autonomy and ownership over mission-critical infrastructure, bridging the gap between cutting-edge blockchain technology and institutional-grade stability.

What You’ll Do

• System Architecture: Architect and build the engineering roadmap for next-generation digital asset systems, leading execution from concept through deployment.

• Asset Lifecycle Management: Serve as the technical owner for the full digital asset lifecycle, including issuance, custody, settlement, and on-chain verification.

• Smart Contract Security: Design, implement, and coordinate audits for mission-critical smart contracts (Rust/Solidity) and their integrating systems.

• Regulatory Engineering: Engineer auditable security controls, such as policy engines and governance rules, that meet strict institutional standards.

• Cross-Functional Leadership: Act as the technical lead between engineering, product, and compliance, translating requirements into actionable designs.

What You’ll Bring

• Industry Experience: 5+ years of software engineering experience delivering complex systems in production.

• Language Mastery: Deep technical command of public chain development, specifically Rust (Solana) and Solidity (EVM).

• Blockchain Depth: Advanced understanding of token standards and integration patterns across different chains.

• System Integration: Proficiency in C++ to interface with and contribute to broader platform systems.

• Security Expertise: Proven expertise in mitigating vulnerabilities (e.g., re-entrancy) and managing the smart contract audit process.

• Operational Excellence: Track record of building fault-tolerant, high-concurrency systems with a commitment to advanced testing frameworks.

• Communication: The ability to communicate complex protocol logic and security trade-offs to both technical and non-technical stakeholders across global teams.

• Education: Bachelor’s degree in Computer Science, Engineering, or a related field (or equivalent professional experience).

Nice To Haves

• Engineering experience in FinTech, high-frequency trading, or high-security sectors

• Knowledge of modern key management (MPC, HSMs) and applied cryptography specific to digital assets

• Experience building infrastructure for indexing, monitoring, and transforming on-chain data

• Familiarity with institutional digital asset custody workflows

Bullish is proud to be an equal opportunity employer. We are fast evolving and striving towards being a globally-diverse community. With integrity at our core, our success is driven by a talented team of individuals and the different perspectives they are encouraged to bring to work every day.