$ whoami

Roble Siyad.

I build systems that move money and data.

I work on pricing systems at Expedia Group, and I like building the kind of software most people only use: exchanges, time-series databases, LLM gateways. All of it runs live on this domain.

View my workcontact →

about

Hi, I'm Roble. I'm a software engineer at Expedia Group, where I work on the pricing systems that apply taxes, fees, promotions, and currency exchange across the group's brands. Before that I built account-security features at Meta and replaced a legacy government data system at DEFRA, which means I've shipped code in three very different environments: big-tech scale, regulated government, and revenue-critical pricing.

Outside work, I learn by building infrastructure from first principles. I've built a mini trading venue with an event-sourced matching engine and two-phase settlement, and an LLM gateway with its own write-ahead log, compressed time-series storage, and query engine. Both are live on this domain, and the demos below are real systems, not mockups.

experience

Software Development Engineer @ Expedia Group

Mar 2026 – Present

  • Build pricing components in Java and Scala that apply taxes, fees, promotions, and currency exchange across Expedia Group brands.
  • Led delivery of QuoteEdit 2.0, a fee-adjustment service, driving a 42% increase in client usage.
  • Shipped tax components in the central pricing response, validated by replaying production traffic.

Software Engineer Intern @ Meta

Jun 2025 – Sep 2025

  • Owned SSO, user management, and 2FA features for Managed Meta Accounts, built with Hack, React, and GraphQL.
  • Shipped Admin Codes, an emergency 2FA flow that cut internal support queries by 82%.
  • Integrated WhatsApp as a 2FA channel with smart SMS fallback, doubling deliveries and saving ~$1,200/day.

Software Developer @ DEFRA

Jan 2024 – Jun 2025

  • Replaced a legacy Water Abstraction system with a Node.js, Hapi, PostgreSQL, and AWS tool, boosting data workflows by 55%.
  • Revamped unit testing with reusable seed data, cutting local test and CI times by 37.5%.
  • Created 20+ PostgreSQL views and built 15+ GOV.UK design-compliant pages with Nunjucks.

projects

exchange.rvsiyad.dev

featured project

exchange

A mini trading venue: orders enter through a REST gateway, cross in an event-sourced matching engine over Kafka, settle as two-phase transfers in TigerBeetle, and stream back to a live order-book dashboard over WebSockets.

  • Java
  • Kafka
  • TigerBeetle
  • WebSockets
  • Docker
[github][live]
scope.rvsiyad.dev/ui

featured project

scope

An OpenAI-compatible LLM gateway with an observability stack built from scratch: write-ahead log, Gorilla-compressed time-series storage, trace store, and a PromQL-lite query engine feeding live dashboards. Point any OpenAI SDK at it with one line.

  • Go
  • Docker
[github][live]

other projects

rvsiyad.dev

This site: a one-page portfolio built with the Next.js App Router, Tailwind CSS v4, and zero client-side JavaScript.

  • Next.js
  • Tailwind CSS
[github]

contact

Get in touch

If you're building something interesting, want to talk systems, or just fancy saying hi, my inbox is open.

Say hello[github][linkedin]