Security Engineer Jobs in Oswego, IL (NOW HIRING)

We are seeking a motivated, hands-on Security Engineer to join our security team. In this role, you will help protect, monitor, and continuously improve the security of our global systems - including cloud (AWS and M365) and on-premises infrastructure. You'll play a central part in risk mitigation, incident response, automation of security operations, and embedding security best practices across our organization.

What you'll do

As a Security Engineer at Optiver, you'll be responsible for monitoring, protecting, and continuously improving the security of our global systems and infrastructure. At Optiver, this means proactive threat prevention, swift identification of security risks, and rapid response to incidents to ensure our systems remain secure under all circumstances. An engineering mindset, attention to detail, and a preference for pragmatic solutions are essential to keeping our systems operating.

In practice, this means you will work on a range of activities in collaboration with the global security team on activities such as:

Security Operations & Monitoring

• Monitor daily security operations, identify threats, investigate alerts, and respond to incidents across cloud and on-prem environments.
• Maintain and tune security tools across AWS, Microsoft 365, endpoints, and network infrastructure.

Cloud & Identity Security

• Strengthen Microsoft 365 and Entra ID security through Conditional Access, MFA, PIM, Defender for Endpoint/Identity/O365, and tenant configuration hardening.
• Implement and support data protection capabilities, including Microsoft Purview, sensitivity labels, DLP, and insider risk policies.

Automation & Engineering

• Build and maintain security automation using Python and PowerShell, with a strong focus on reducing manual processes and improving detection and response.
• Integrate systems using APIs (Graph API, REST, etc) to enhance security workflows.
• Work with AI and our AI engineering teams to ensure the security of the environment

Risk Assessment & Security Controls

• Perform vulnerability assessments, review system configurations, and develop practical mitigation strategies.
• Conduct security reviews of systems, cloud workloads, and new technologies.
• Ensuring and assuring our security controls are effective and working as intended

Incident Response

• Lead or contribute to incident response activities including investigation, containment, communication, and remediation.
• Analyze logs, IOCs, and behavior patterns using SIEM tools and threat intelligence.

Collaboration & Enablement

• Work closely with engineering, technology, and business teams to embed security best practices.
• Provide guidance on secure architecture, access controls, and identity management.
• Support user education and uplift security behaviors across the business.

What you'll get

You'll join a culture of collaboration and excellence, surrounded by curious thinkers and creative problem-solvers. Motivated by a passion for continuous improvement, you'll thrive in a supportive, high-performing environment alongside talented colleagues, collectively tackling some of the toughest challenges in the financial markets.

In addition, you'll receive:

• The opportunity to work alongside best-in-class professionals from over 40 different countries
• Highly competitive compensation package including performance-based bonus structure
• 401(k) match up to 50%
• Comprehensive health, mental, dental, vision, disability, and life coverage
• 25 paid vacation days alongside market holidays
• Extensive office perks, including breakfast, lunch and snacks, regular social events, clubs, sporting leagues and more

Who you are

You are a hands-on security engineer with strong technical fundamentals and a passion for building secure, scalable systems. You may come from a background in Security Engineering, Security Operations, Cloud Security, Identity & Access Management, DevSecOps, or a related field.

You likely bring experience in several of the following areas:

• Securing and supporting cloud environments, particularly AWS, including services such as IAM, GuardDuty, CloudTrail, Security Hub, AWS Config, and KMS
• Working with Microsoft security technologies including Entra ID, Conditional Access, Multi-Factor Authentication (MFA), Privileged Identity Management (PIM), Microsoft Defender, and Secure Score
• Using security tools such as EDR, SIEM, vulnerability management, SOAR, CASB, or related technologies
• Investigating security events, responding to incidents, and managing security risks across cloud and on-premises environments
• Managing identity and access controls, including RBAC, PAM, SSO, and federation technologies such as SAML, OAuth, and OIDC
• Supporting and securing Windows and Linux environments
• Applying networking fundamentals including TCP/IP, DNS, VPNs, proxies, and firewalls to secure enterprise systems
• Building automation and tooling using Python and/or PowerShell
• Integrating systems through APIs and working with version control systems such as Git
• Implementing or supporting data protection technologies such as Microsoft Purview, data loss prevention (DLP), classification, and information protection solutions

Beyond your technical experience, you:

• Approach security challenges with an engineering mindset and prefer pragmatic, effective solutions to unnecessary complexity
• Look for opportunities to automate repetitive work through scripting, tooling, and emerging technologies, including AI-enabled security workflows
• Have hands-on experience in security engineering, security operations, or DevSecOps, with a track record of monitoring, incident response, and risk reduction
• Stay curious about evolving threats, cloud technologies, detection techniques, and emerging security trends
• Communicate effectively across technical and non-technical teams and can clearly articulate security concepts to a variety of audiences
• Are comfortable collaborating with engineers, infrastructure teams, and business stakeholders, and constructively challenging assumptions when needed
• Take ownership of problems from investigation through resolution and enjoy working in a fast-paced, highly collaborative environment

We recognize that great candidates may not meet every qualification listed above. If you're excited about the role and believe you can contribute, we encourage you to apply.

Who we are 

At Optiver, our mission is to improve the market by injecting liquidity, providing accurate pricing, increasing transparency and stabilizing the market no matter the conditions. With a focus on continuous improvement, we prioritize safeguarding the health and efficiency of the markets for all participants. As one of the largest market making institutions, we are a respected partner on 100+ exchanges across the globe.

Our differences are our edge. Optiver does not discriminate on the basis of race, religion, color, sex, gender identity, sexual orientation, age, physical or mental disability, or other legally protected characteristics.