Software Engineer - Security

OverviewThis position can be based out of San Francisco, New York, or remote (we accept candidates from the following states: AZ, CA, CO, CT, FL, GA, HI, IL, MA, MI, MN, MT, NC, NJ, NV, NY, OH, OK, OR, PA, TN, TX, UT, WA, WI).Modern Treasury’s mission is to build the most trusted financial infrastructure for global money movement. We’re looking for a Security Engineer to design and strengthen the controls that protect our payment infrastructure. You’ll enable as well as build secure, compliant financial products while contributing directly to the reliability and automation of our security and infrastructure systems.Modern Treasury is expanding deeper into money movement. We’re building new products that will let customers move funds across both traditional rails and emerging technologies, including stablecoins. You’ll help design, deploy and operate the security controls that make this possible and set the foundation for compliant, programmable money movement at scale.This role is hands-on security engineering with heavy focus on automation.About The RoleThis role focuses on application, product, and infrastructure security, and sits at the intersection of security, platform, payments engineering, and infrastructure. You’ll shape how Modern Treasury manages risk at scale and design the systems that make programmatic, compliant money movement possible. We are looking for someone who can influence security strategy, drive DevSecOps automation and contribute to architectural design.Your work will ensure that as we grow into new products and payment rails, we continue to move fast while keeping trust, compliance, and safety at the core of our platform.What You’ll DoLead application security across our payment platform, including secure code review, threat modeling, and security architecture for new productsOwn product security for new payment rails, including FBO account structures, stablecoin integration, and enhanced compliance featuresDesign and implement DevSecOps tooling and automation to improve security posture across CI/CD and infrastructurePartner with engineering teams to embed security into the development lifecycle through automation, secure design patterns, and security championsDrive security architecture decisions for customer-facing APIs, authentication systems, and data protection controlsBuild monitoring and detection capabilities for application-layer threats, API abuse, and fraud patternsDesign infrastructure monitoring, automation, and remediation practices that keep our systems resilient and trustworthyCollaborate with Compliance and Legal to ensure product features meet regulatory requirements (BSA/AML, KYC/KYB, state money transmission)Influence technical strategy across Product, Platform, and Infrastructure teams on security and risk managementRequired ExperienceWHAT YOU SHOULD HAVE6+ years in security engineering, with 3+ years focused on application and product securityStrong experience with:Full-stack application security (frontend, backend, APIs)Authentication and authorization systems and identity managementInfrastructure automation related to security (AWS, Docker, CI/CD pipelines)Fraud detection, prevention, and abuse mitigation in payment or financial productsSecure SDLC practices and developer security toolingExperience with incident response and security monitoringKnowledge and experience with application security for Ruby on Rails, GraphQL, JavaScript, React, and containerized environmentsPayments engineering experience, ideally including fraud prevention and risk controls in money movement systemsWhat Sets You Apart2+ years in payments or fintech, with a deep understanding of money movement security challengesFamiliarity with compliance and regulatory standards for money movement, such as PCI DSS, BSA/AML, and KYC/KYBExperience with payment processing security across ACH, wires, card networks, and emerging railsExperience building controls for fraud detection, chargeback prevention, and abuse mitigation in payment systemsExperience integrating security into DevOps workflows (e.g., Buildkite, IaC, AWS security automation)Experience with stablecoin security, blockchain integrations, or crypto payment railsTrack record of balancing pragmatic risk management with business velocityDemonstrated ability to lead security initiatives across multiple teams without direct authorityTECHNOLOGIES WE USERuby on Rails for our backend frameworkReact, GraphQL, and Tailwind CSS on the front endPostgres for our databaseAWS for infrastructure and hostingDocker for containerizationBuildkite for continuous integrationRegTech and anti-fraud platformsAbout Modern TreasuryModern Treasury is the operating system for money movement. Our payments platform combines a suite of APIs and dashboards to help companies unlock new payments revenue, strengthen customer experiences, and drive efficiency through their business. Our end-to-end platform moves enterprises forward with faster payments, efficient workflows, full data visibility.Modern Treasury is committed to equal employment opportunity and does not discriminate in any employment opportunities or practices based on an individual's race, color, creed, gender (including gender identity and gender expression), religion (all aspects of religious beliefs, observance or practice, including religious dress or grooming practices), marital status, registered domestic partner status, age, national origin or ancestry (including language use restrictions and possession of a driver’s license issued under California Vehicle Code section 12801.9), natural hair, physical or mental disability, political affiliation, medical condition (including cancer or a record or history of cancer, and genetic characteristics), sex (including pregnancy, childbirth, breastfeeding or related medical condition), genetic information, sexual orientation, military and veteran status or any other consideration made unlawful by federal, state, or local laws. It also prohibits unlawful discrimination based on the perception that anyone has any of those characteristics, or is associated with a person who has or is perceived as having any of those characteristics.Modern Treasury participates in E-Verify and will provide the federal government with your Form I-9 information to confirm that you are authorized to work in the U.S.Compensation Range: $170K - $240K