Infrastructure Security Engineer in United States

About the Team Security is foundational to OpenAI’s mission to ensure that artificial general intelligence benefits all of humanity. The Security organization protects OpenAI’s technology, people, and products by building and operating deeply technical systems that must work reliably at massive scale. Our work underpins OpenAI’s commitments around safety, privacy, and security across research, products, and emerging platforms. The Host Assurance team exists to make bare metal a dependable, scalable foundation for OpenAI: secure by default, verifiable in practice, and resilient across providers and operating models. We operate at the trust boundary between physical hardware and cloud-scale orchestration, ensuring that hosts are eligible to safely run workloads with predictable security properties and auditability. About the Role OpenAI is seeking a Security Engineer, Host Assurance to help build the trust foundations for bare-metal platforms across OpenAI’s global infrastructure. This is a deeply hands-on engineering role for a builder who can design, implement, and operate the core security infrastructure that establishes trust in hardware platforms before they are eligible to run workloads. Success in this role requires strong technical judgment, the ability to work comfortably at low levels of the stack, and a practical mindset for building systems that are secure, reliable, and usable in fast-moving production environments. The systems you build will sit on the critical path of OpenAI’s frontier infrastructure investments and will directly shape how large amounts of compute are brought online - securely, responsibly, and at global scale - underpinning long-lived commitments around privacy, security, and reliability. You will partner closely with infrastructure, research, and confidential computing initiatives—including novel hardware platforms and emerging deployment models– to make the secure path the easiest path. This role is well suited for engineers who enjo

We believe that the way people interact with their finances will drastically improve in the next few years. We’re dedicated to empowering this transformation by building the tools and experiences that thousands of developers use to create their own products. Plaid powers the tools millions of people rely on to live a healthier financial life. We work with thousands of companies like Venmo, SoFi, several of the Fortune 500, and many of the largest banks to make it easy for people to connect their financial accounts to the apps and services they want to use. Plaid’s network covers 12,000 financial institutions across the US, Canada, UK and Europe. Founded in 2013, the company is headquartered in San Francisco with offices in New York, Washington D.C., London and Amsterdam. We are hiring for a leader for the newly forming Detection and Response team at Plaid. Our mission is to protect Plaid's financial infrastructure by detecting and responding to suspicious activity across the company. We are responsible for the entire lifecycle of detection and response, including detection infrastructure, AI triage and response, investigation tooling, Red Teaming, and Fraud Operations. Security is foundational to the trust thousands of businesses and millions of consumers place in Plaid, and we work directly to reduce risks and enable our business to move faster and safer. As the Head of Detection and Response, you will be the founding leader responsible for standing up and evaluating Plaid's detection and response team. You will lead a specialized technical team of analysts and engineers, gain deep experience partnering with the CISO and cross-functional engineering leaders, and build critical security infrastructure at scale. This is a unique leadership opportunity to manage a team that encompasses traditional security operations alongside Red Teaming and Fraud Operations, directly impacting Plaid's security posture and long-term stability. Responsibilities: Form and set up Plaid’

About the Team The Infrastructure Engineering function sits within IT and is responsible for reliably building, deploying, and operating critical on prem and hybrid environments that power internal services and critical R&D environments. This is an early, high-leverage technical role focused on applying strong Site Reliability Engineering discipline to environments where uptime, safety, recoverability, and security are non-negotiable. This person helps replace bespoke, one-off infrastructure with standardized infrastructure-as-code building blocks that compound reliability and operational leverage as OpenAI scales. About the Role We are looking for an experienced Site Reliability Engineer working on security infrastructure to design, build, and operate reliable, secure, and scalable infrastructure that underpins identity, access, endpoint, and shared platform services across the company. In this role, you will be a senior technical owner for infrastructure and identity systems end to end, from architecture and implementation through policy enforcement, upgrades, recovery, and day-two operations. You will build durable, production-grade platforms that remove operational friction, enforce security by default, and enable teams to move faster with confidence. This role is well suited for a hands-on senior engineer who thrives in ambiguity, enjoys owning complex systems end to end, and raises the reliability and security bar by replacing fragile implementations with standardized, repeatable infrastructure. This role is based in our San Francisco HQ and requires in-office presence. In this role, you will: Design, build, and operate reliable infrastructure across on-prem, hybrid, shared, and product adjacent environments. Establish standardized infrastructure patterns that replace bespoke implementations with repeatable, auditable, secure-by-default systems. Own the lifecycle of critical infrastructure platforms, including provisioning, deployment, upgrades, patching,

About Ramp Ramp is building the smart infrastructure for finance teams, embedded in the transaction flow of every dollar a business spends. We automate how over $200B in annualized spend flows in and out of 70,000+ companies: authorizing payments, flagging risk, categorizing spend, and closing books. The problems are high-stakes, data-dense, and unforgiving. We hire people with high agency and high urgency. We look for slope over intercept. We care less about where you trained and more about what you’ve built. At Ramp, everyone is a builder who owns problems end to end and makes consequential decisions that shape the outcome. The median Ramp customer saves 5% and grows revenue 16% in their first year – far in excess of businesses operating without Ramp. We believe every ambitious company deserves the same. If you want to build systems that directly shape how companies move and manage billions, Ramp is the place to do it. About the Role The Security Engineering team helps make Ramp the most secure place for our customers to collect, manage, and put to work their business’ financial information Our work centers in three areas: Ramp builds products with an eye for security Ramp detects and responds to threats before they cause harm Security powers Ramp’s growth Check out our Engineering Blog for more on our tech stack, mission and values! What You’ll Do Drive our cloud security roadmap: review our cloud deployments to identify opportunities for improvement Design and build security-focused infrastructure primitives and integrate them into our existing products and development processes Lead remediation of prioritized issues across our technology stack Partner with infrastructure, data, and devops teams to design and deploy solutions that are inherently secure What You Need Minimum 5 years of experience building software Minimum 3 years of experience building in AWS (with Terraform) A strong sense of ownership: you need to drive projects from inception to scaling it in

A World-Changing Company Palantir builds the world’s leading software for data-driven decisions and operations. By bringing the right data to the people who need it, our platforms empower our partners to develop lifesaving drugs, forecast supply chain disruptions, locate missing children, and more. The Role As a Security Systems Engineer at Palantir, you are responsible for implementing, designing, and maintaining the physical security systems that ensure the protection of Palantir’s people, assets, intellectual property, and reputation. You lead research and evaluations for the latest technology, security infrastructure, policies, procedures, systems, and applications, looking for easy-to-use capabilities that reduce button clicks and ultimately give time back to the operator. You will be collaborating with technical teams to develop and maintain end-to-end project plans and ensure on-time delivery. Your technical expertise is second only to your integrity and genuine passion for security and technology. As a member of the Global Security and Investigations team, you work with security professionals, architects, lawyers, and software and network engineers to deliver a safe and secure environment for your fellow employees. Palantir is a global company, so you'll lead physical security projects all over the world. You'll work hard to break down barriers between teams by communicating your knowledge and goals effectively across time zones and other physical and virtual barriers. *Please note this role is NOT for cyber security or information security positions* Core Responsibilities Design and oversee the technical aspects of your projects from conception to full deployment. Systems naturally break and need maintenance. You'll work with vendors and end users to find the best solutions for a problem, in the shortest possible time. Leverage both system and software engineering skills in order to address the needs of all teams within Globa

Replit is the agentic software creation platform that enables anyone to build applications using natural language. With millions of users worldwide, Replit is democratizing software development by removing traditional barriers to application creation. About the Role We are seeking a mid-level Infrastructure Vulnerability Management Engineer with a strong background in Cloud Security, DevSecOps, and Infrastructure-as-Code (IaC). In this role, you will bridge the gap between security, compliance, DevOps, and Platform engineering teams. You will identify infrastructure misconfigurations, secure multi-cloud environments, and manage continuous vulnerability lifecycles across cloud workloads, containers, and data repositories to satisfy strict regulatory compliance frameworks. You will also serve as a technical infrastructure responder during security incidents, deploying real-time cloud or network countermeasures to protect our production ecosystem. What You'll Do Core Responsibilities Infrastructure Scanning & Triage: Perform continuous security scanning across our cloud posture and workloads. Review, validate, and prioritize flaws and misconfigurations based on CVSS scores, real-world exploitability, and infrastructure network exposure. Posture Management & Visibility : Own and optimize Cloud Security Posture Management (CSPM), Kubernetes Security Posture Management (KSPM), and Data Security Posture Management (DSPM) tools to ensure uniform compliance, prevent data leakage, and maintain hardened baselines. Infrastructure-as-Code (IaC) Security: Configure, tune, and embed automated IaC security scanning tools into CI/CD pipelines to identify architectural risks (e.g., overly permissive IAM, public S3 buckets/Cloud Storage) before they are deployed to production. Workload & Container Security: Manage the continuous vulnerability scanning lifecycle for container images, registries, and Virtual Machines (VMs), partnering with SRE and Platform teams to build aut

About the Team Security is at the foundation of OpenAI’s mission to ensure that artificial general intelligence benefits all of humanity. The Security team protects OpenAI’s technology, people, and products. We are technical in what we build but operational in how we execute, and we support every product and research effort at OpenAI. Our tenets include prioritizing for impact, enabling researchers and developers, preparing for future transformative technologies, and fostering a strong, collaborative security culture. About the Role OpenAI is seeking a Principal Software Engineer to join the Infrastructure Security (InfraSec) team. InfraSec safeguards the core of OpenAI’s research and production environments: GPU supercomputing clusters, multi-cloud infrastructure, datacenters, networking, storage, and the critical services that power our frontier AI models. Our charter spans everything from bare-metal hardware and firmware to Kubernetes clusters, service meshes, and the data pathways that carry highly sensitive model weights and user data. As a Principal Software Engineer, you will set technical direction and drive execution of critical foundational services, such as authentication systems, egress/ingress proxies, access brokers, and key management platforms, that demand high standards of reliability, scalability, and software craftsmanship. These systems form the security backbone of OpenAI’s customer and supercomputing environment and must remain robust under intense scale and adversarial pressure. In this role, you will: Own the architecture and roadmap for one or more core security services (e.g., authN/Z, policy enforcement, secure proxies, key management), taking them from design to rollout to long-term operation. Design and implement planet-scale security systems that provide strong guarantees across hardware, operating systems, Kubernetes, networks, and CI/CD: balancing security, reliability, latency, and developer ergonomics. Lead cross-functional launches

Who We Are Notion is the collaborative AI workspace where teams and agents think together . We're building one place where your knowledge, projects, meetings, and AI tools live side by side, so work is faster, clearer, and less fragmented. Millions of individuals, small teams, and large companies run their work on Notion. Notinos (our employees) are customer zero in bringing this future of work to life. We care about craft, building things that last, and the belief that great work is still fundamentally human. Our goal isn’t to ship the next feature. Each and every team of Notinos is working to set the standard for how humans work together in the AI era. From building a business’s system of record to making and managing AI agents to automating away the busy work, we care deeply about giving our customers more time for their life’s work. About the Role: Millions of people use Notion every day, and we’re growing quickly. The Infrastructure Security team’s mission is to build a secure-by-default foundation across Notion’s technical stacks—architecting systems that make the secure path the easy path. As an IC4 on this team, you’ll own meaningful infrastructure security problems end-to-end: from identifying risk, to designing pragmatic controls, to shipping secure defaults that scale across engineering. This role can be based in either San Francisco or New York City. We work from our offices on Mondays, Tuesdays and Thursdays (our Anchor Days) because we do our best thinking and building together in person. We’re looking for someone who’s excited to work alongside the team during those days. What You'll Achieve: Proactively enhance the security posture of our AWS accounts and cloud infrastructure. Create secure frameworks for secrets management and authentication/authorization. Design and deploy robust Identity and Access Management (IAM) solutions. Provide guidance and education on security and privacy best practices to cross-functional partners. Participate in (and hel

About Ramp Ramp is building the smart infrastructure for finance teams, embedded in the transaction flow of every dollar a business spends. We automate how over $200B in annualized spend flows in and out of 70,000+ companies: authorizing payments, flagging risk, categorizing spend, and closing books. The problems are high-stakes, data-dense, and unforgiving. We hire people with high agency and high urgency. We look for slope over intercept. We care less about where you trained and more about what you’ve built. At Ramp, everyone is a builder who owns problems end to end and makes consequential decisions that shape the outcome. The median Ramp customer saves 5% and grows revenue 16% in their first year – far in excess of businesses operating without Ramp. We believe every ambitious company deserves the same. If you want to build systems that directly shape how companies move and manage billions, Ramp is the place to do it. About the Role You'll be the architect of our endpoint security posture across the full fleet — macOS, Windows, and BYOD mobile devices. You'll build secure-by-default controls with Terraform and GitOps, harden endpoints at scale, and automate the full device lifecycle so nothing depends on a human remembering to click the right button. You'll partner with IT, SecOps, and engineering teams to sharpen our telemetry and detections, mentor other engineers, and raise the bar on what "low-friction security" actually means. Everything you ship will be auditable, measurable, and built for the long run. We're also thinking seriously about how corporate security evolves in an agentic world — where AI agents act on behalf of employees and traditional identity and endpoint assumptions break down. You'll help us shape that answer. What You’ll Do Write and ship MDM policy as code — configuration profiles, remediation scripts, and enforcement rules across macOS, Windows, and mobile — with staged rollouts and rollback from day one Build patch automation that close

About Ramp Ramp is building the smart infrastructure for finance teams, embedded in the transaction flow of every dollar a business spends. We automate how over $200B in annualized spend flows in and out of 70,000+ companies: authorizing payments, flagging risk, categorizing spend, and closing books. The problems are high-stakes, data-dense, and unforgiving. We hire people with high agency and high urgency. We look for slope over intercept. We care less about where you trained and more about what you’ve built. At Ramp, everyone is a builder who owns problems end to end and makes consequential decisions that shape the outcome. The median Ramp customer saves 5% and grows revenue 16% in their first year – far in excess of businesses operating without Ramp. We believe every ambitious company deserves the same. If you want to build systems that directly shape how companies move and manage billions, Ramp is the place to do it. About the Role The Product Security team helps make Ramp the most secure place for our customers to collect, manage, and put to work their business’ financial information. Our work centers in three areas: Ramp builds products with an eye for security Ramp detects and responds to threats before they cause harm Security powers Ramp’s growth Check out our Engineering Blog for more on our tech stack, mission and values! What You’ll Do Build security-focused application primitives and integrate them into our existing products Design and deploy platform-level mitigations to common security issues Lead remediation of prioritized issues across our technology stack: collaborating with other engineers to triage and fix vulnerabilities discovered internally, through penetration testing, and through our bug bounty program Partner with engineering teams to design and deploy solutions which are inherently secure Champion the use of tooling (linters, static analysis, posture assessment scanners, query inspectors, etc.) which help Ramp engineers build secure system

About Ramp Ramp is building the smart infrastructure for finance teams, embedded in the transaction flow of every dollar a business spends. We automate how over $200B in annualized spend flows in and out of 70,000+ companies: authorizing payments, flagging risk, categorizing spend, and closing books. The problems are high-stakes, data-dense, and unforgiving. We hire people with high agency and high urgency. We look for slope over intercept. We care less about where you trained and more about what you’ve built. At Ramp, everyone is a builder who owns problems end to end and makes consequential decisions that shape the outcome. The median Ramp customer saves 5% and grows revenue 16% in their first year – far in excess of businesses operating without Ramp. We believe every ambitious company deserves the same. If you want to build systems that directly shape how companies move and manage billions, Ramp is the place to do it. As Ramp’s founding Privacy engineer, you will build a privacy program that powers Ramp’s growth while earning trust from customers and prospects. What You’ll Do Build privacy-focused application primitives and integrate them into our existing products Partner with other engineering teams to design and deploy solutions which are inherently privacy-centric and secure Improve, implement, and deploy data retention and anonymization strategies across our environment Track shifting legal standards (alongside with Ramp’s Privacy Counsel) and update Ramp systems and processes to match What You Need Minimum of 4 years of experience building software Minimum of 2 years of experienced focused on platform, privacy, and/or security Desire to work in a fast-paced environment, continuously grow, and master your craft Ability to turn business and product ideas into engineering solutions Nice-to-Haves Working knowledge of data-protection legal requirements Experience with Python (Flask), React, and AWS (ECS, as well as other core services) Benefits available to all

About the Role Discover your future at Citi Working at Citi is far more than just a job. A career with us means joining a team of more than 230,000 dedicated people from around the globe. At Citi, you'll have the opportunity to grow your career, give back to your community and make a real impact. Job Overview Citi's Integrated Digital Assets Platform (CIDAP) is at the vanguard of institutional blockchain adoption — and security is its foundation. As digital assets move from innovation to regulated infrastructure, the cryptographic integrity of every transaction, wallet, and key lifecycle operation becomes mission-critical. We are building the security layer that the world's most sophisticated financial institution can trust. We are seeking a Senior Security Engineer (VP) to join our New York-based Digital Assets Platform engineering team. This is a hands-on, Java-focused backend engineering role for a security-minded engineer who understands both the craft of secure software development and the cryptographic primitives that underpin digital asset custody, signing, and key management. You will sit inside the core engineering team — writing production code every day — while being the resident authority on cryptographic design patterns, HSM integration, MPC protocols, and security architecture. Your work will directly protect billions of dollars of digital asset infrastructure used by institutional clients worldwide. Key Responsibilities Design, develop, and maintain security-critical backend services in Java — including cryptographic libraries, key management APIs, signing wor

Here at Datadog, we think about offensive security a little bit differently. We embrace automation and AI to run adversary simulations continuously across a massive cloud-native environment, and we expect our offensive engineers to build the tooling that makes that possible. We're looking for a Senior Security Engineer who can execute sophisticated red team operations, write the code that scales them, and take an AI-first approach to offensive security engineering. At Datadog, we place value in our office culture - the relationships and collaboration it builds, and the creativity it brings to the table. We operate as a hybrid workplace to ensure our Datadogs can create a work-life harmony that best fits them. What You'll Do: Plan and execute red team engagements end-to-end, simulating real-world threat actors across cloud infrastructure (AWS, GCP), Kubernetes, CI/CD pipelines, and corporate environments Build and maintain custom offensive tooling, automation frameworks, and engagement infrastructure, treating offensive operations as a software engineering problem Develop custom payloads and evasion capabilities tailored to Datadog's environment and modern defensive controls (EDR, SIEM, network monitoring) Improve the efficiency of offensive operations through thoughtful use of automation and AI, accelerating reconnaissance, vulnerability analysis, and reporting workflows Partner with the Detection & Response team on purple team exercises to validate detection logic, improve alert fidelity, and influence threat models Translate offensive findings into concrete improvements by working directly with defensive security and engineering teams to close gaps Who You Are: You have 5+ years of hands-on experience in offensive security (red teaming, penetration testing, or adversary simulation) with a track record of operating against mature, well-defended environments You write production-quality code (Python, Go, or similar), can build your own tools, and automate your w

About the Team Security is at the foundation of OpenAI’s mission to ensure that artificial general intelligence benefits all of humanity. The Security team protects OpenAI’s technology, people, and products. We are technical in what we build but are operational in how we do our work, and are committed to supporting all products and research at OpenAI. Our Security team tenets include: prioritizing for impact, enabling researchers, preparing for future transformative technologies, and engaging a robust security culture. About the Role We’re seeking an exceptional Principal-level Offensive Security Engineer focused on deep, hands-on penetration testing of OpenAI’s agent-powered products, infrastructure, and model-integrated application surfaces. You’ll assess complex systems end to end, identify realistic vulnerabilities, validate exploitability and impact, and partner closely with engineering teams to drive durable fixes. This role will be primarily focused on continuously testing our agent-powered products like Codex and Operator. These systems are uniquely valuable targets because they’re rapidly evolving, can perform sensitive actions on behalf of users, and have large, diverse attack surfaces. You will play a crucial role in securing our agents by finding vulnerabilities that emerge from the interactions between the applications, infrastructure, tools, and models that power them. You’ll have the chance to not only find vulnerabilities, but actively drive their resolution, build reusable testing approaches, automate offensive security workflows with cutting-edge technologies, and use your attacker perspective to improve the security of OpenAI’s products. In this role you will: Conduct deep penetration tests of OpenAI’s agent-powered products, including web applications, APIs, cloud services, identity and authorization flows, CI/CD systems, and model-integrated product surfaces. Continuously hunt for exploitable vulnerabilities in the interactions between the appli

🚀 About WRITER WRITER is where the world's leading enterprises orchestrate AI-powered work. Our vision is to expand human capacity through superintelligence. And we're proving it's possible – through powerful, trustworthy AI that unites IT and business teams together to unlock enterprise-wide transformation. With WRITER's end-to-end platform, hundreds of companies like Mars, Marriott, Uber, and Vanguard are building and deploying AI agents that are grounded in their company's data and fueled by WRITER's enterprise-grade LLMs. Valued at $1.9B and backed by industry-leading investors including Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is rapidly cementing its position as the leader in enterprise generative AI. Founded in 2020 with office hubs in San Francisco, New York City, Seattle, Austin, Chicago, and London, our team thinks big and moves fast, and we're looking for smart, hardworking builders and scalers to join us on our journey to create a better future of work with AI. 📐 About the role This is where security meets innovation at enterprise scale. As a staff security engineer, applications at WRITER, you'll be building the security foundations that protect the AI systems powering some of the world's most recognizable brands. You'll work at the intersection of application security, AI infrastructure, and developer enablement—partnering with engineering teams to embed security into every line of code while ensuring our platform remains both powerful and trustworthy. The opportunity is massive: you'll help define how enterprise AI applications are secured, from threat modeling our LLM architectures to building automated security controls that scale across our growing platform. This isn't about saying "no"—it's about finding creative ways to say "yes, and here's how we do it securely." You'll tackle challenges that most security engineers never encounter: securing AI agents, protecting training data pipelines, and designing controls for systems tha