Circles

Lead Security Engineer

Remote Lead Security Engineer role with clear candidate location fit.

PostedJul 11, 2026

Eligible countries1 accepted country

Seniority signalSenior

Work settingRemote

Accepted candidate locations

USA

Role overview

Readable role content extracted into sections for faster review.

Circles.Life: A wholly-owned digital lifestyle telco brand based in Singapore, Circles.Life is powered by Circles’ SaaS platform and pioneering go-to-market strategies. It is the digital market leader in Singapore and has won numerous awards for marketing, customer service, and innovative product offerings beyond connectivity.
Circles Aspire: A global provider of Communications Platform-as-a-Service (CPaaS) solutions. Its cloud-based Experience Cloud platform enables enterprises, service providers and developers to deliver and scale mobile, messaging, IoT, and connectivity services worldwide.
Jetpac: Specializing in travel tech solutions, Jetpac provides seamless eSIM roaming for over 200 destinations and innovative travel lifestyle products, redefining connectivity for digital travelers. Jetpac was awarded Travel eSIM of the Year.

Lead threat modeling (STRIDE, PASTA, or equivalent) for new applications, features, and major platform changes
Conduct security architecture reviews for applications, APIs, cloud infrastructure, and third-party services before go-live
Define secure design patterns and reference architectures; provide hands-on security guidance at every stage of the SDLC, not just at release gates

Own the Application Security program end-to-end: SAST, DAST, SCA, and API security testing — tool selection, policy tuning, and triage workflows
Integrate security testing natively into CI/CD pipelines and DevSecOps workflows so findings surface before merge, not after deploy
Assess REST and GraphQL APIs against the OWASP API Security Top 10 (broken object/function-level authorization, excessive data exposure, rate limiting, business logic abuse)
Partner with engineering leads to prioritize findings by exploitability and business impact, and drive remediation within agreed SLAs

Plan and execute internal penetration tests across web applications, APIs, cloud, and infrastructure; scope and oversee external pen test engagements
Manually validate findings to separate real risk from noise before they reach engineering backlogs
Own the vulnerability management lifecycle — from discovery through remediation to verified closure — and continuously tighten SLAs as maturity improves

Serve as a technical escalation point for security incidents; lead or support incident response — triage, containment, root cause analysis, and post-incident reviews
Improve detection and response capability through SIEM/SOAR rule tuning, informed directly by incident and threat intelligence learnings
Close the loop between offensive findings (pen test, threat model) and detective controls (SIEM/SOAR), so known risks are also monitored, not just documented

Build automation in Python (or equivalent) for security scanning, findings de-duplication, ticketing, and reporting workflows
Integrate security tooling across CI/CD and SOC operations to eliminate repetitive manual work and shorten detection-to-remediation time
Treat automation as a core deliverable, not a side project — every recurring manual security task is a candidate for a pipeline

10-12 years of hands-on experience in Application Security and Security Engineering
Demonstrated, hands-on strength in:Threat modeling and secure architecture reviewMicroservice architecturePenetration testing[Web, API, Mobile] and vulnerability managementSAST, DAST, SCA, Containers, IaC including container/Kubernetes workload security..Software supply-chain security SOC operations and incident responseDevSecOps and CI/CD security integrationPython (or equivalent) scripting for security automation
Threat modeling and secure architecture review
Microservice architecture
Penetration testing[Web, API, Mobile] and vulnerability management
SAST, DAST, SCA, Containers, IaC including container/Kubernetes workload security..
Software supply-chain security
SOC operations and incident response
DevSecOps and CI/CD security integration
Python (or equivalent) scripting for security automation
Solid working knowledge of the OWASP Top 10, OWASP API Security Top 10, secure coding practices, and cloud security fundamentals
Capability to identify AI-specific vulnerabilities such as prompt injection, data poisoning, system prompt leakage, and insecure output handling.
Ability to read and understand code to identify vulnerabilities; proficiency in Java or Go (Golang) is a strong plus.
Strong communicator, able to influence engineering teams on remediation priority and translate technical risk into terms executives act on

Threat modeling and secure architecture review
Microservice architecture
Penetration testing[Web, API, Mobile] and vulnerability management
SAST, DAST, SCA, Containers, IaC including container/Kubernetes workload security..
Software supply-chain security
SOC operations and incident response
DevSecOps and CI/CD security integration
Python (or equivalent) scripting for security automation

Certifications: OSCP, OSWE, GWAPT, GPEN, CISSP, or equivalent
Experience securing AWS, Azure, or GCP environments, and Kubernetes/container workloads
Hands-on experience with SIEM/SOAR platforms (e.g., Splunk, Sentinel, XSOAR, or similar)
Familiarity with security maturity frameworks: OWASP SAMM, BSIMM, or NIST CSF
Exposure to securing AI/LLM implementations

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