~/karlagunday

Karl Agunday

Technical Lead, Senior Software Engineer
๐Ÿ‡ต๐Ÿ‡ญ Davao City, Philippines

Strong foundation in building robust, scalable systems that deliver measurable business impact. Deep technical expertise, a track record of leadership, and a genuine passion for learning.

Karl Agunday

tech stack

TypescriptJavascriptNodeJSRubyRuby on RailsNestJSPHPC# .NetReactJSReduxNextJSExpressJSReact NativeTailwindJestGraphQLPostgresMySQLMongoDBDockerAWSKubernetesDatadogFullstoryCodexClaude

experiences

Aug 2025 โ€” May 2026

Senior Software Engineer@Open Home Loans

Founding engineer on a fintech platform helping Australians find the best mortgage deal for their money.

  • Architected a front-end design system following atomic design principles, enforcing consistency with the design team
  • Helped engineer resilient Open Banking integrations via exponential backoff polling and response caching despite no webhook support
  • Authored a script to auto-generate a TypeScript SDK from the back-end's OpenAPI spec and set up AI-assisted dev workflows with rigorous oversight
C# .NetTypescriptReact NativeTailwindDocker
Jan 2023 โ€” Jun 2025

Technical Lead@PayMongo

Led engineering teams on a real-time, high-volume payments platform and was recognized with a technical leadership award.

  • Co-architected a high-volume QRPH system with queue-based processing, horizontal scaling, rate limiting, and idempotency across the InstaPay lifecycle
  • Led the Hold & Capture team championing best practices, open communication, and mentorship to consistently ship high-quality work
  • Stabilized e-wallet and direct online banking integrations (GCash, Maya), resolving recurring issues from inconsistent provider APIs
RubyRuby on RailsPostgresTypescriptNodeJS
Jul 2022 โ€” Jan 2023

Senior Software Engineer@PayMongo

Cards team โ€” full payment lifecycle from authorization to settlement.

  • Worked across feature development and bug fixes spanning auth and capture flows, retry handling, and transaction state validation
  • Gained hands-on experience with 3D Secure, frictionless authentication, acquiring bank integrations, and BSP compliance
RubyRuby on RailsPostgresTypescriptNodeJS
Jul 2021 โ€” Jun 2022

Senior Software Engineer@Heyday

Full-stack engineer on an HR perks platform.

  • Delivered new features and maintained the codebase across both frontend and backend
  • Independently owned Next.js frontend development despite it being new territory, building complex UI behaviors without compromising on quality
NestJSReactJSNextJSPostgresGraphQL

projects

01.work

QRPH Acceptance

for PayMongoยท2024ยทvisit โ†—

Lets merchant customers scan and pay directly using their bank or e-wallet app โ€” no card needed. Built on top of the InstaPay network and the full QRPH payment lifecycle, making checkout faster and more accessible for everyday Filipinos.

RubyPostgresReactJS
02.work

Hold & Capture

for PayMongoยท2023ยทvisit โ†—

A pre-authorization payment feature for businesses that need to hold a payment until a product or service is fulfilled โ€” think deliveries, rentals, or bookings. Merchants authorize the charge upfront and only capture it when they're ready.

RubyPostgresReactJS
03.personal

Personal Website

passion projectยท2026

This site โ€” a single-page developer profile. Hand-built in React with a terminal-flavored dark mode and live tweaks.

NextJSContentfulSass
04.personal

Beewise Budget Tracker

passion projectยท2025

A personal expense and budget tracker for staying on top of monthly spending โ€” without relying on a bank app. Tracks multiple budget categories with a monthly breakdown dashboard. Built as a PWA and self-hosted on a home server.

NestJSPostgresReactJS

contact

hello@karlagunday.com

Building software that matters? Know of an exciting engineering role? Or just passionate about writing code? I'd love to hear about it.

or, let's connect โ†’