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Hello! I'm Eugene, a software engineer with over a decade of experience building web and backend applications. I enjoy turning complex problems into clean, scalable software and collaborating with cross-functional teams to deliver value. I continually learn new technologies, embrace best practices, and love applying agile principles to shipping reliable software on time.…

Eugene Sergio Castro de los Santos

Web Developer, Programmer, Front-End Developer, +3

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Hello! I'm Eugene, a software engineer with over a decade of experience building web and backend applications. I enjoy turning complex problems into clean, scalable software and collaborating with cross-functional teams to deliver value. I continually learn new technologies, embrace best practices, and love applying agile principles to shipping reliable software on time.…

Available to hire

Hello! I’m Eugene, a software engineer with over a decade of experience building web and backend applications. I enjoy turning complex problems into clean, scalable software and collaborating with cross-functional teams to deliver value.

I continually learn new technologies, embrace best practices, and love applying agile principles to shipping reliable software on time.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Language

English

Fluent

Work Experience

Senior Backend Software Developer, HR Systems at Spinifex IT Philippines

October 1, 2024 - February 20, 2025

Developed minor, well-scoped features to grant and delete access to user profiles in the administrative portal. Exposure to CircleCI, Docker, and Kubernetes deployment stack with monitoring using Datadog and Grafana. Development technologies included PHP, Java, DropWizard, MongoDB, Terraform, AWS SQS, and OpenSearch.

Senior Backend Software Developer, HR Systems at i Scale Solutions Philippines

October 1, 2024 - August 20, 2025

Developed minor, well-scoped features to grant and delete access to user profiles in the administrative portal; exposure to CircleCI, Docker, and Kubernetes deployment stack; development technologies include PHP, Java, DropWizard, MongoDB, Terraform, AWS SQS, and OpenSearch.

Full-Stack Engineer at Singapore Client (via 2 IT companies)

March 1, 2022 - September 1, 2024

Developed an automation portal from scratch using event-driven design, Angular, and Spring; created a CQRS proof-of-concept to demonstrate event sourcing using Spring Boot and Axon; delivered HNW portal frontend to production; aligned UI with Figma design, implemented authentication, and integrated with Salesforce; security hardening and production support; upgraded client web app from Angular 14 to 17.

Java Senior Associate at Spinifex IT Philippines

December 1, 2021 - March 1, 2022

Java backend development with event-driven design principles; contributed to automation portal using Angular and Spring; implemented CQRS proof-of-concept with Axon; delivered production-ready HNW portal and authentication flow; integrated with Salesforce.

Java Senior Associate at Cognizant Philippines

December 1, 2021 - March 1, 2022

Worked on Manulife Singapore project with backend API development, API validation, and Salesforce integration; emphasized Java/Spring-based solutions and production readiness.

Software Engineer at Spinifex IT Philippines

November 1, 2018 - September 1, 2020

Developed automation portal from scratch using Angular and Spring; implemented security measures (pentest, DAST, JWT, CSP); aligned UI with Figma design; upgraded CWS web app (Angular 14 → 17) and provided production support.

Software Engineer at UST Global

April 1, 2016 - November 1, 2018

Specializes in full-stack Java development; practices Agile methodology; collaborated with cloud-focused teams; contributed to microservices/API work; mentored Cobol engineers transitioning to Java.

Senior Software Engineer at UST Global

April 1, 2016 - November 1, 2018

Specializes in full-stack Java development; delivered monthly enhancements for a US retail client; practiced Agile, unit testing, and CI/CD; built microservices and collaborated with Cobol engineers for modernization.

Java Developer at Talas Data Intelligence, Inc.

July 1, 2015 - April 1, 2016

Backend development for retail and financial sectors; built Big Data APIs using Spark, HBase, Kafka; contributed to Digital Ads Exchange project ahead of schedule.

B2B Systems Integrator at Open Text (GXS Acquisition)

August 1, 2013 - December 1, 2014

Established 900+ B2B cloud setups for multi-protocol connectivity; collaborated with analysts and project teams; applied UNIX shell scripting for deployment; maintained high on-time completion and utilization.

Open Text Specialist at Open Text (GX Acquisition)

August 1, 2013 - December 31, 2014

Established 900+ B2B cloud connectivity setups; UNIX shell scripting for directory and map deployments; managed high-utilization deployments in the first six months.

Analog Test System (ATS) Engineer at ROHM LSI Design Philippines, Inc.

May 1, 2011 - July 1, 2013

Maintained in-house data-processing system automating IC design verification; automated frontend/backend features; documented references and improved system speed.

R&D Programmer at ROHM LSI Design Philippines, Inc.

November 1, 2010 - July 1, 2013

Maintained automated engineering tool for IC simulation/testing; developed frontend/backend features; documented technical references; automated 30+ key features across multiple SDLC cycles.