Eris Jacey Masagca

Developer. Diver. Dreamer.

I build solutions that are meticulously elegant.

I'm a backend engineer who takes code quality seriously.

Currently at Visa, I build payment infrastructure that handles millions of transactions daily while maintaining 99.999% availability. I specialize in Java, Spring Boot, and MongoDB, with a focus on reliability, performance at scale, and integrating AI capabilities.

Outside of work, I'm usually at my local gym trying to set personal records, or trying to 100% whatever game I'm currently obsessed with. Occasionally, you'll find me 30 meters underwater somewhere, or wandering around a new city.

Jun 2023 — Present

Software Engineer @ Visa

Value-Added Services (Transaction Services)Singapore
  • Own and maintain critical Visa Transaction Controls and Visa Flexible Credentials APIs integrated with VisaNet, serving issuer applications with sub-300ms response times and 99.999% availability
  • Led development of real-time operational analytics platform providing granular DB performance metrics, reducing incident remediation time by 50%+ through pre-emptive anomaly detection
  • Executed MongoDB migration from replica sets to sharded clusters, supporting scale from 300M to 5B+ cards with zero downtime
  • Pioneered AI integration: deployed production AI feature validating merchant category codes, cutting client onboarding time by 90%; developed MCP server for internal debugging
  • Mentored 3 new engineers as onboarding buddy, achieving <2 week time-to-first-commit
JavaSpring BootMongoDBKafkaReactSpring AIGrafana

YAGFI - yet another good first issue

OSS

GitHub "good first issue" aggregator backend

Multiple contributions to an open-source project that helps developers find beginner-friendly issues. Implemented license features, country detection, developer tooling (Makefile), and the project's first integration test.

JavaSpring Boot
View all 5 contributions

TakeLeave.sg

Personal

PTO tracking and forecasting for Singapore workers

A personal leave tracking web app with running balance forecasts, a what-if simulator for planning hypothetical leave, and JSON export/import for backups. All data stays in localStorage; no backend, no auth.

What I Built

  • Pure computation engine with zero UI/framework imports: generates timelines, balances, and chart data
  • Storage service abstraction layer over local storage
  • What-if simulator for planning hypothetical leave scenarios
  • Sick leave overlaid as toggleable second line on forecast chart
  • 5-step onboarding wizard for first-run configuration
TypeScriptNext.jsTailwind CSS

PantryPal

Personal

Smart pantry inventory manager

A mobile-first application to track pantry items, manage expiration dates, and reduce food waste with smart notifications.

JavaSpring BootPostgreSQLFlyway

Coming soon...

Let's Connect

Open to senior software engineering opportunities in Singapore.

or reach out directly