Principal Security Engineer: AI, Cloud & Blockchain Defense

Circle; Washington; On-site; USD 128,000 - 197,000; Full time

Job summary

Circle is seeking a Principal Security Engineer to lead detection, response, and security engineering across cloud, blockchain, and AI surfaces. You will own critical security projects, drive incident response, and collaborate with engineering teams to fortify Circle's defenses.

The role requires deep AWS security expertise, hands-on experience with SIEM/SOAR, and a strong background in threat detection for blockchain and crypto-native systems.

Qualifications

• 10+ years of experience in detection, response, or security engineering.
• 3+ years of experience commanding security incidents, especially those involving engineering.
• Deep cloud security knowledge in AWS environments: IAM, identity federation, KMS, EKS/container attack patterns, runtime exploitation, and CSPM tooling.
• Working knowledge of blockchain and crypto-native threats: wallet and custody attack patterns, on-chain monitoring, protocol-level risks.
• Hands-on experience with AI tooling to accelerate work and defend against shadow AI and MCP/tool integrations.

Responsibilities

• Lead security projects and deliverables across Circle teams, with on-call duties during working hours and occasional nights/weekends.
• Proactively identify and respond to threats across cloud, endpoint, blockchain, and AI surfaces.
• Develop detection coverage for cloud-native and crypto-native threats, including on-chain anomalies and custody interactions.
• Extend detection for AI-specific risks and integrate detection across SIEM and SOAR platforms.
• Lead incident response, investigations, and cross-team collaboration to resolve security events.
• Provide security guidance to various internal groups, participate in threat modeling and audits.

Skills

Team collaboration

Crisis management

Cloud security (AWS)

IAM / identity federation

SIEM / SOAR

Programming (Python, Golang)

Threat hunting

Blockchain/crypto threats

AI tooling awareness

On-call / incident response

Tools

Panther

Tines

Wiz

AWS (EKS)

GCP / OCI

SIEM platforms

Case management tooling

Job description

Circle is seeking a Principal Security Engineer to lead detection, response, and security engineering across cloud, blockchain, and AI surfaces. You will own critical security projects, drive incident response, and collaborate with engineering teams to fortify Circle's defenses.

The role requires deep AWS security expertise, hands-on experience with SIEM/SOAR, and a strong background in threat detection for blockchain and crypto-native systems.