Security Engineer

Security Engineer – Crypto High-Frequency Trading

Location: New York, London, Singapore, or Dubai.  In-office full time.

About Selini

Selini is a global trading firm focused on systematic trading and venture investing in the digital asset space.

Overview

We are seeking a Security Engineer with 3–15 years of experience to protect and enhance the security of our trading infrastructure, internal systems, and crypto operations. This role combines traditional systems security, application and network defense, and blockchain-specific threat modeling. You’ll work closely with infrastructure, software, and trading teams to ensure the highest standards of security across our on-prem and cloud environments.

Key Responsibilities

• Design, implement, and maintain security controls across Linux-based trading and research environments.
• Lead efforts in system hardening, network segmentation, identity management, and incident response.
• Develop and manage detection, monitoring, and alerting systems for system and crypto-specific threats.
• Conduct regular vulnerability assessments, threat modeling, and penetration testing across infrastructure and smart contract interfaces.
• Secure integration points between on-prem, cloud, and crypto custody systems (e.g., HSMs, MPC wallets).
• Collaborate with developers to ensure security best practices in code, build pipelines, and container environments.
• Investigate security incidents and perform forensic analysis when required.
• Automate routine security operations using Python, Bash, or Ansible.
• Manage compliance and operational controls for key exchanges, APIs, and wallets used in trading operations.
  
  

Required Qualifications

• 3–15 years of experience in security engineering or systems administration in Linux environments (Rocky Linux preferred).
• Deep understanding of network security, firewalling, VPNs, and intrusion detection systems.
• Proven experience with cloud security (AWS preferred), including IAM, key management, and VPC hardening.
• Strong knowledge of Linux hardening, system logging, patch management, and secure automation.
• Strong scripting and automation skills in Python, Bash, or Ansible.
  
  

Preferred Skills

• Knowledge of crypto-specific attack surfaces — exchange API security, private key management, and wallet infrastructure.
• Deep understanding of private key management:
• Best practices for storage, encryption, retrieval, signing, and generating private keys
• Familiarity with hardware wallets and multi-sig solutions such as Gnosis Safe and Squads
• Best practices for cold storage
• Familiarity with the programming model of the primary blockchains including EVM and Solana
• Understanding of Solidity (and/or Vyper) programming.
• Familiarity with common vulnerabilities (e.g., reentrancy, integer overflows, flash loan exploits, front-running/MEV, access control flaws).
• Experience conducting audits or using automated tools (Slither, MythX, Echidna, Foundry).
• Ability to reason about state changes, upgradeability, and complex financial logic in contracts.

Blockchain & Protocol Layer Knowledge

• Understanding how Ethereum and Solana work at the consensus and execution layer.
• Awareness of cross-chain bridges, their security assumptions, and risks.
• Ability to evaluate protocol designs (DEXes, lending platforms, stablecoins) for systemic weaknesses.

• Experience securing blockchain nodes, custody systems, or trading bots.
• Background in low-latency or high-performance trading environments.
• Experience conducting security audits, code reviews, or penetration testing in production environments.
• Awareness of relevant compliance frameworks (SOC2, ISO 27001) in trading or financial contexts.
  
  

Soft Skills & Culture Fit

• Analytical and methodical problem solver with a proactive mindset.
• Comfortable in high-pressure, real-time trading environments.
• Strong communication skills, with the ability to collaborate across infrastructure, trading, and software teams.
• Desire to continually improve and automate — security as code mindset.

We’re a close-knit team that values:

• High ownership and initiative
• Curiosity, intellectual honesty, and rapid learning
• Clear, direct communication
• Working together toward shared goals — no ego, no politics

We hire people who love building, solving, and improving — and who want to learn from and contribute to a team of exceptional peers.

Compensation & Benefits:

• Very competitive compensation, with strong upside based on contribution and performance
• Competitive holiday allowance 
• Free daily Deliveroo lunch
• High-spec office and technology
• Team socials
• Global company offsites and development opportunities