Senior Security Engineer & Client Security Lead

OneSeven Tech; United States; Remote; USD 78,000 - 89,000; Full time

Benefits offered by this job

Paid time off

Referral bonus

Remote work

Job summary

OneSeven Tech is seeking a senior security engineer to lead hands-on security across internal and client-facing systems, combining application and cloud security, incident response, and advisory services. This role emphasizes building repeatable cybersecurity services and playbooks.

You will conduct threat modeling, oversee penetration tests, manage SIEM/EDR, and guide clients through scoping, remediation, and executive reports while turning complex work into defined, measurable offerings.

Qualifications

• Production experience securing applications and cloud environments, including web/API vulnerabilities, authorization, identity, secure development, and remediation.
• Experience with authorized penetration testing, defensive controls, EDR/SIEM monitoring, and incident-response processes.
• Practical experience administering SSO/MFA, employee access, endpoints, business SaaS, and user support.
• Ability to use AI-assisted security tools with authorization, containment, output checks, and audit trails.
• Automation skills using scripting, APIs, or infrastructure-as-code.
• Strong written and verbal English for client communication, including during incidents.
• Ability to turn technical work into repeatable processes and clearly scoped services with measurable outcomes.

Responsibilities

• Conduct threat modeling, secure-design and architecture reviews, and integrate security checks into development workflows.
• Plan and run authorized penetration tests, attack-surface assessments, and scoped red-team exercises under clear rules of engagement.
• Assess AI-enabled applications for prompt injection, data exposure, excessive permissions, and cross-client access risks.
• Configure and tune endpoint detection, SIEM, detections, and SOAR playbooks; conduct threat hunting and purple-team exercises.
• Lead incident triage, containment, and recovery, keeping clients informed throughout.
• Administer internal IT, including onboarding and offboarding, SSO/MFA, access reviews, device management, and business software.
• Advise clients through discovery, scoping, assessment readouts, remediation workshops, and executive reports.
• Work with leadership to develop reusable service playbooks, templates, scopes, and delivery estimates.

Skills

Security engineering

Threat modeling

Penetration testing

Incident response

Cloud security

Secure development

Automation (scripting / IaC)

English communication

Tools

EDR

SIEM

SOAR

Job description

Role overview

Establish and lead hands-on security engineering across internal systems and software delivered to clients. This senior individual-contributor role combines application and cloud security, incident response, internal IT administration, and client advisory work, while helping shape repeatable cybersecurity services.

Responsibilities

• Conduct threat modeling, secure-design and architecture reviews, and integrate security checks into development workflows.
• Plan and run authorized penetration tests, attack-surface assessments, and scoped red-team exercises under clear rules of engagement.
• Assess AI-enabled applications for prompt injection, data exposure, excessive permissions, and cross-client access risks.
• Configure and tune endpoint detection, SIEM, detections, and SOAR playbooks; conduct threat hunting and purple-team exercises.
• Lead incident triage, containment, and recovery, keeping clients informed throughout.
• Administer internal IT, including onboarding and offboarding, SSO/MFA, access reviews, device management, and business software.
• Advise clients through discovery, scoping, assessment readouts, remediation workshops, and executive reports.
• Work with leadership to develop reusable service playbooks, templates, scopes, and delivery estimates.

Requirements

• Production experience securing applications and cloud environments, including web/API vulnerabilities, authorization, identity, secure development, and remediation.
• Experience with authorized penetration testing, defensive controls, EDR/SIEM monitoring, and incident-response processes.
• Practical experience administering SSO/MFA, employee access, endpoints, business SaaS, and user support.
• Ability to use AI-assisted security tools with authorization, containment, output checks, and audit trails.
• Automation skills using scripting, APIs, or infrastructure-as-code.
• Strong written and verbal English for client communication, including during incidents.
• Ability to turn technical work into repeatable processes and clearly scoped services with measurable outcomes.

Nice to have

• Consulting, multi-client delivery, managed security, or cybersecurity service development experience.
• AI/LLM security, adversary emulation, purple teaming, detection engineering, or SOAR experience.
• Familiarity with OWASP ASVS, MITRE ATT&CK, or NIST CSF.
• Experience with brownfield modernization or greenfield product development; practical certifications are welcome.

Benefits and work setup

• Remote, full-time contract open to candidates in Argentina, Chile, Colombia, Brazil, Uruguay, Peru, and Mexico.
• Monthly compensation of $7,000–$8,000 USD, paid bi-weekly.
• Initial six-month contract, with a longer-term arrangement described as possible afterward.
• Paid time off and a referral bonus are listed; specific PTO terms are not provided.