Staff Application Security Engineer

Vestwell•Austin, TX

2d•$190,000 - $200,000•Hybrid

About The Position

Vestwell is seeking a Staff Application Security Engineer to secure the applications and identity integrations that power its financial technology products. The role focuses on analyzing and protecting NestJS applications, strengthening application security practices throughout the software development lifecycle, and owning security for identity capabilities in both identity-provider (IdP) and relying-party (RP) OIDC integrations and internal application use. The engineer will partner with software engineering, platform, infrastructure, and product teams to identify risk early, design practical mitigations, and make secure-by-default development easier. The position combines hands-on application security expertise with deep knowledge of modern authentication and authorization protocols. The role is based in one of Vestwell’s New York City, Austin, King of Prussia, or Scottsdale offices and is part of the company’s hybrid in-office operation. The expected base salary range is $190,000–$200,000, with eligibility for the Company Bonus Pool and new-hire equity.

Requirements

Professional experience in application security, product security, software engineering, or a closely related discipline.
Strong experience securing Node.js and TypeScript applications; hands-on NestJS experience is required or highly preferred.
Deep understanding of OAuth 2.0 and OpenID Connect, including common implementation pitfalls and secure deployment patterns.
Practical experience with IdP and RP implementations, integrations, or security assessments.
Strong understanding of authentication and authorization, including RBAC, least privilege, separation of duties, claims, scopes, permissions, sessions, tokens, and service-to-service access.
Ability to review code and architecture across APIs, web applications, background jobs, and distributed services.
Experience with web and API security risks, including OWASP Top 10, OWASP API Security Top 10, broken access control, SSRF, injection, XSS, CSRF, insecure deserialization, request forgery, misconfiguration, and supply-chain risk.
Familiarity with secure token handling, JWT validation, key management, JWKS, signing algorithms, rotation, revocation, and token-storage considerations.
Experience integrating security into CI/CD and developer workflows without creating unnecessary friction.
Strong communication skills and ability to explain security risks and tradeoffs to technical and non-technical audiences.
A pragmatic, collaborative approach to identifying meaningful risk, proposing proportional controls, and helping teams implement them.

Nice To Haves

Experience with OAuth 2.1 guidance, FAPI, PAR, JAR, DPoP, sender-constrained tokens, or other advanced OAuth security patterns.
Experience with identity platforms or libraries such as Auth0, Okta, Keycloak, Cognito, Azure AD/Entra ID, or comparable systems.
Experience with SAML integrations for single sign-on solutions.
Experience with API gateways, service meshes, microservices, event-driven systems, and cloud-native deployments.
Familiarity with containers, infrastructure as code, secrets management, and cloud IAM.
Experience with security tooling such as Burp Suite, Semgrep, CodeQL, Snyk, Dependabot, OWASP ZAP, or equivalent tools.
Familiarity with security standards and guidance such as OWASP ASVS, OWASP SAMM, NIST SSDF, NIST 800-63, and relevant OAuth/OIDC specifications.
Experience conducting penetration tests, adversarial reviews, or purple-team exercises.
Relevant security certifications or equivalent demonstrated experience.

Responsibilities

Analyze NestJS and TypeScript applications for authentication, authorization, input-validation, injection, session, API, business-logic, and data-protection vulnerabilities.
Establish and evolve secure development patterns for NestJS, including guards, interceptors, middleware, decorators, validation, error handling, logging, configuration, and dependency management.
Own or contribute to the security architecture of OIDC integrations and identity-platform capabilities as both an identity provider and a relying party.
Design, review, and assess OAuth 2.0 and OpenID Connect flows, including authorization code with PKCE, refresh tokens, client authentication, scopes, consent, state, nonce, redirect URI validation, token lifetimes, and key rotation.
Help define and enforce authorization models using RBAC and, where appropriate, claims-based or policy-based access control.
Review access-control boundaries across services, APIs, tenants, users, roles, permissions, and administrative functions.
Lead or participate in threat modeling, security design reviews, architecture reviews, and secure code reviews.
Build security requirements, reusable libraries, reference implementations, and developer guidance to reduce recurring risk.
Improve security testing and detection through SAST, DAST, software composition analysis, secret scanning, API testing, dependency monitoring, and targeted security testing.
Partner with engineering teams to remediate vulnerabilities, prioritize findings by exploitability and business impact, and verify fixes.
Monitor application and identity security signals, support incident investigations, and contribute to playbooks for account takeover, token compromise, authorization bypass, credential abuse, and related events.
Help maintain security documentation, standards, risk exceptions, and evidence needed for audits and customer assurance.
Stay current on application security, identity, OAuth/OIDC, browser security, API security, cloud security, and emerging attack techniques.