Sr. Java Developer - Authentication and Application Security

Description Remote Our client seeks a Sr. Java Developer - Authentication and Application Security to lead the design and build of a custom authentication platform for a portfolio of consumer-facing websites. The role centers on identity, authentication, authorization, and application security leadership rather than traditional feature development. The consultant will guide architecture and technology selection, advise senior Java engineers, and drive implementation patterns for a secure, maintainable, and cost-effective platform as the organization evaluates transitioning away from a third-party solution. The consultant will also support migration planning, risk identification, and standards definition in collaboration with engineering, architecture, product, and senior leadership stakeholders. Due to client requirements, applicants must be willing and able to work on a w2 basis. For our w2 consultants, we offer a great benefits package that includes Medical, Dental, and Vision benefits, 401k with company matching, and life insurance. Rate: $80.00 to $85.00/hr. w2 JN -102026-109093 Responsibilities Lead the architecture and design of a custom authentication platform to replace existing solutions. Evaluate open-source authentication frameworks and recommend a secure and sustainable platform. Provide expertise across authentication, authorization, identity management, and application security. Partner with senior Java architects and developers to establish technical direction. Guide implementation using Java, microservices, Spring, and Spring Security. Define secure architectural patterns for user authentication across multiple websites and applications. Advise on SSO, federated identity, token-based authentication, one-time passwords, and passwordless options. Establish security standards, technical controls, and implementation guidelines. Identify architectural risks, vulnerabilities, scalability concerns, and operational challenges early. Provide practical guidance based on prior authentication-platform experience, including anti-patterns and lessons learned. Support evaluation and selection of supporting technologies. Collaborate with engineering, architecture, product, and senior leadership stakeholders. Assist with migration planning from the current environment to the new platform. Leverage approved AI-assisted development tools while maintaining security, quality, and oversight. Experience Requirements Approximately 10+ years in software engineering, application security, identity engineering, or related fields. Deep expertise in authentication, authorization, identity management, and application security. Direct experience building, architecting, implementing, or leading an enterprise authentication platform. Strong understanding of modern authentication standards and security practices. Experience with Java-based applications, microservices, and Spring technologies. Experience evaluating or implementing open-source authentication frameworks. Knowledge of Spring Security, SSO, SAML, JWT, one-time password, and passwordless authentication. Ability to influence architect-level engineers and design decisions. Ability to distinguish secure, sustainable solutions from risky or hard-to-maintain approaches. Strong communication skills with engineering leaders, product stakeholders, and senior management. Ability to work independently in a fully remote environment with a distributed team. Preferred: prior end-to-end design of an authentication platform and migration from commercial services. Preferred: experience supporting multiple high-traffic consumer websites and seasonal traffic patterns. Preferred: background as a senior application security engineer, identity architect, or security architect. Preferred: leadership of authentication-platform modernization or migration initiatives. Preferred: familiarity with additional modern identity standards and enterprise AI-assisted engineering tools.