Open to opportunities

Angel Varela

@angelvarela

Message

Software engineer focused on event-driven microservices, secure authentication, and performance optimization at scale.

United States

Message

What I'm looking for

I’m looking to build reliable event-driven microservices and secure, production-ready authentication—leading zero-downtime migrations, improving performance, and applying practical offline/LLM capabilities to deliver dependable systems.

I design and build distributed, event-driven microservice architectures that handle high-volume transaction processing with Spring Boot, Apache Kafka, and PostgreSQL. I’ve led zero-downtime database migrations using bi-directional replication and dual-write consistency verification to keep critical production transitions reliable.

I also build secure authentication systems, including WebAuthn passwordless login with backend registration/sign-in flows and React passkey autofill experiences. From optimizing N+1 query bottlenecks with JPQL and native strategies to automating delivery with GitHub Actions, I focus on dependable systems, strong testing, and production-grade observability.

Experience

Work history, roles, and key accomplishments

Software Engineer

American Express (via Insight Global)

Jun 2025 - Mar 2026 (9 months)

Executed an Oracle-to-PostgreSQL zero-downtime migration using Kafka bi-directional replication and continuous dual-writes, ensuring cross-database consistency through cutover. Built WebAuthn passwordless authentication (backend and React conditional UI), automated QA/code review in GitHub Actions, and implemented monitoring/logging and OpenAPI documentation for migration and authentication servic

Java Spring Boot Oracle PostgreSQL Kafka Google Pub Sub BigQuery WebAuthn React Gradle Maven GitHub Actions Artifactory OpenSearch SLF4J Logback OpenAPI Swagger Splunk Docker CI CD

Software Engineer

American Express (via Mthree)

Mar 2023 - May 2025 (2 years 2 months)

Built reactive Java microservices using Vert.x, delivering frontend-facing APIs to data-access services serving millions of daily login and user-data requests. Improved PostgreSQL read performance by resolving N+1 query issues (JPQL projections, JOIN FETCH, and native queries), contributed to Java 17–21 migration, and strengthened reliability via JUnit/Mockito testing and JMeter load testing.

Java Vert.X Spring Boot PostgreSQL Oracle JDBC Fetch HikariCP Junit Mockito JMeter Docker Docker Compose Gradle Maven GitHub Actions Artifactory Splunk OpenSearch SLF4J Jackson

Software Engineer

RSM US LLP (via Cook Systems)

Jul 2022 - Nov 2022 (4 months)

Built Dell Boomi platform integrations to automate enterprise data flows between client SaaS systems using transformation logic and validation rules. Authored data-mapping specifications defining transformation requirements and cross-system synchronization validations.

Dell Boomi JavaScript SOAP REST APIs XML Data Mapping API Integration