Application Security Engineer

About the role

At OneStream, we're on a mission to empower every Finance organization and professional to exceed their potential. Our global teams span continents, cultures, and time zones, united by a shared purpose as we build the operating system for modern Finance and help organizations move with greater speed, clarity, and confidence.

That mission comes to life through our people. Behind every innovation, customer success, and milestone are talented people working together to make a difference. That's why we're looking for people who are bold enough to think big, authentic in how they lead and collaborate, curious about what's possible, and committed to delivering results.

Want a closer look before you apply? Explore our Careers site to learn more about our people, culture, and benefits.

Summary

We are looking for an Application Security Engineer to join the Information Security team. In this role, you will help keep the OneStream platform secure by triaging and validating findings from application security tools, partnering with engineering teams on practical remediation, and supporting security design reviews and threat modelling for new features throughout the SDLC. You will also use automation and AI-assisted tooling to take on repetitive work, such as reviewing and summarizing findings, so the team can focus on higher-impact security problems.

The ideal candidate has experience in software engineering and security, with a solid foundation in secure development practices, familiarity with application security tools (SAST, SCA, and DAST), and a passion for securing our platform for our customers. Working knowledge of C# and .NET is a bonus. We are looking for a go-getter who is eager to learn, collaborates well with teams across all levels of the organization, and brings a pragmatic approach to security that keeps delivery moving. This position requires the ability to explain and discuss technical details with both technical and non-technical audiences.

Primary Duties and Responsibilities

- Triage and validate findings from application security tools (SAST, SCA, and DAST), prioritizing by exploitability and real-world risk.

- Partner with Development and Engineering teams to remediate vulnerabilities with clear, practical guidance.

- Participate in security architecture reviews and threat modelling for new features and services.

- Integrate and tune application security tooling in CI/CD pipelines so security checks fit naturally into developer workflows.

- Use AI-assisted tools and automation to streamline repetitive tasks such as reviewing and summarizing findings, removing duplicates and false positives, creating tickets, and reporting.

- Write scripts and lightweight tooling to automate recurring security workflows.

- Review the SDLC and software supply chain, including third-party dependencies, to identify opportunities to improve security.

- Perform targeted manual validation of findings when needed to confirm impact.