Backend & platform engineering
Building the systems behind secure access.
I'm Bryant, a Software Engineer II at UKG working in identity and access management. My focus is backend services, authentication security, and enterprise SSO.
UKG – present
Professional work / UKG
Engineering trust.
Selected contributions to the authentication and identity systems that enterprise applications depend on.
Authentication securityStrengthening access controlsSecurity improvements around IP-based access controls in enterprise authentication flows.
Authentication
Access policies
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The problem
IP-based access policies depend on trustworthy request context. The authentication layer needs to apply those policies consistently.
My contribution
At UKG, I contributed to security improvements around IP-based access controls in enterprise authentication flows, with a focus on the boundary between incoming requests and access decisions.
Engineering focus Request trust, policy enforcement, and authentication security.
Enterprise single sign-onMaking certificate rotation smootherSAML multi-certificate support and coordinated service changes for enterprise SSO.
SAML / Auth0
Kafka / Java
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The problem
Enterprise SSO needs to keep working while certificates change. Supporting certificate overlap also requires validation and coordinated updates across services.
My contribution
I contributed to SAML multi-certificate support across Auth0 integration, database migrations, and Kafka events. The work included CA-signed certificate validation and resilience handling to support uninterrupted certificate rotation.
Engineering focus Service coordination, certificate validation, and continuity during change.
Tools & practice
From service code
to delivery.
My work spans backend implementation, automated testing, and the systems that support a release.
- Backend & identity
- Java, Spring Boot, Auth0, SAML / SSO, Kafka, JPA, Hibernate
- Testing & delivery
- JUnit, Mockito, GitHub Actions, Docker, Git, Gradle, Maven
- AI in my workflow
- Codex and Claude Code are part of my day-to-day software development workflow.
- Additional background
- Python, C, PostgreSQL, MySQL, Linux / Unix, Agile & Scrum
Bryant Villarreal
Software engineer. Always learning.
The person behind the work
A foundation in CS.
A focus on real systems.
I'm a Software Engineer II at UKG, where I've worked since September 2022. I became an Associate Software Engineer in May 2023 and was promoted to Software Engineer II in January 2025. Identity and access management brings together the parts of software engineering I care about: security, backend systems, and the details that make them work together.
I completed my master's in Computer Science at Florida International University in December 2025. My academic background includes software security, computer networking, and operating systems.
Education / Florida International University
M.S. in Computer Science
Florida International University
B.S. in Computer Science
Magna cum laude GPA 3.71
Undergraduate project archive
Projects from my undergraduate years at FIU, completed before joining UKG.
What comes next
Let's talk about
what's next.
I'm interested in backend and platform engineering roles on teams building AI products and large-scale systems.
bryantavillarreal@gmail.com