Senior Software Engineer  ·  Open to Opportunities

Yuxin (Estella)
Huang

8+ years building large-scale backend systems in Java. From distributed payment platforms at Finfare to open-source work at Meta, I architect systems that are reliable, observable, and built to scale.

📍 Irvine, CA · UCI Master of Software Engineering · GPA 3.9 / 4.0
diary.txt 🍵 tea #6 lofi playlist 3am shipping
8+
Years in Java
3
Top-tier Companies
1M+
Users Served
21k★
Meta OSS Contribution
01 / TECHNICAL SKILLS
LANGUAGES
Java Kotlin TypeScript JavaScript Python OCaml C# SQL
BACKEND & FRAMEWORKS
Spring Boot Spring Cloud Hibernate RESTful API Microservices Concurrent Programming Distributed Systems
DATABASE & MESSAGING
MySQL Redis PostgreSQL Elasticsearch MongoDB Kafka RabbitMQ RocketMQ
CLOUD & DEVOPS
AWS Docker Kubernetes GitHub Actions Jenkins DataDog Nginx LaunchDarkly
02 / FEATURED PROJECTS
01
Cloud-Native Deployment Platform
// Finfare · AWS Infrastructure
Designed production-grade AWS infrastructure (ECS, S3, CloudFront, API Gateway, CDK) supporting multiple environments with high availability and zero downtime. Led a modular GitHub Actions CI/CD pipeline with diff-based execution for app code, infrastructure, and documentation. Implemented Blue-Green deployments with automated health checks and rollback strategies.
↳ Reduced build & deployment time by 40–60%
AWS ECS CDK GitHub Actions CloudFront Blue-Green Deploy S3
02
Rewards & Billing Platform
// Finfare · Payment-Adjacent Systems
Built large-scale billing and invoicing systems connecting merchants, banks, advertisers, and publishers. Ingested and managed 10K+ brands with optimized SQL schemas and queries. Took full ownership from design → implementation → deployment → operation. Provided technical leadership to a team of 2–4 engineers.
↳ Full ownership across entire product lifecycle
Java Kotlin Spring Boot MySQL DataDog
03
User Redemption Service
// Finfare · Cashback & Bank Transfers
End-to-end cashback redemption service — validated pending requests, calculated accumulated cashback, generated NACHA files for bank transfers, and encrypted/decrypted files via AWS S3 pre-signed URLs. Delivered customer-facing APIs for purchase history visualization and email notifications for redemption status.
↳ Secure event-driven file pipeline with pre-signed S3 URLs
Java Spring Boot Hibernate AWS S3 NACHA
04
Distributed Flow — Meta Open Source
// Meta · Facebook Flow (21,000+ GitHub Stars)
Contributed to Flow, Facebook's popular open-source JS static type checker. Migrated architecture from standalone to distributed using OCaml. Implemented parallel job execution, content-addressable storage uploads, remote server migration, and dependency graph generation for JS type-check jobs.
↳ Faster developer feedback · reduced resource usage on local machines
OCaml Distributed Systems Open Source Static Analysis Functional Programming
05
Distributed Shopping Cart & Commodity Search
// Zhangmen Education · 290,000+ Clients
Led distributed shopping cart for 290k+ users with Nacos + Spring Cloud Feign — real-time price calculation with discount and coupon logic, Redis caching for fast access. Built Elasticsearch-powered commodity search across 100k+ items with custom shard numbers, analyzers, and field weight tuning via RocketMQ batch processing.
↳ Best-match search · Redis cache · RocketMQ batch at scale
Spring Cloud Elasticsearch Redis RocketMQ Nacos
03 / WORK EXPERIENCE
Aug 2023 — Present
Irvine, CA
Software Engineer III Current
// Finfare
Leading backend development of large-scale payment-adjacent platforms in Java and Kotlin. Architected cloud-native AWS infrastructure, billing systems, and cashback redemption services. Provided technical leadership to a team of 2–4 engineers across design, code review, testing, and deployment.
Feb 2023 — Feb 2024
Irvine, CA
Software Engineer
// UC Irvine Digital Learning Lab
Led full-stack development of an AI-powered story generator platform — input keywords, output paragraphs and illustrations. Delivered both frontend and backend using Java, Spring Boot, JavaScript, and AWS.
Jun — Sept 2022
Menlo Park, CA
Software Engineering Intern
// Meta
Contributed to Flow — Facebook's open-source JavaScript static type checker with 21,000+ GitHub stars. Migrated from standalone to distributed architecture using OCaml, improving speed of developer feedback and reducing resource usage on developer machines.
Jan — Jul 2021
Shanghai, China
Senior Software Engineer
// Zhangmen Education
Led distributed shopping cart and commodity search platforms serving 290k+ clients. Built Elasticsearch-powered search with custom shard and analyzer tuning across 100k+ commodities. Implemented Redis caching and RocketMQ batch APIs for performance and scalability.
Feb 2019 — Oct 2020
Shanghai, China
Java Backend Developer
// China Pacific Life Insurance
Built a distributed application framework adopted by 2,000+ development teams. Developed document search services, a SonarQube scanning platform for 2,000+ Java projects, and rewrote Canal for automatic MySQL → Elasticsearch data synchronization.
Apr 2018 — Jan 2019
Shanghai, China
Java Backend Developer
// Shanghai Rock FinTech
Built bank accounting management system serving 1,000,000+ clients. Analyzed transaction risks and reconstructed core deposit/withdrawal features using RabbitMQ and Oracle, improving stability and reducing processing lag.
04 / ABOUT ME
"I became an engineer because of a TV show. Seriously."

I grew up in Jingzhou, a small city along the Yangtze River. Then I spent four incredible years in Yichang — a place with mountains, clear rivers, and scenery so beautiful it barely felt real — getting my bachelor's degree and having some of the best years of my life.

Around that time, the show Silicon Valley was everywhere. I thought those engineers were the coolest people alive — building things from nothing, changing the world from a garage. So I messaged a friend who actually worked in Silicon Valley and asked: "How do I get there?" That one conversation changed everything.

I started learning Java, built little games, and immediately got hooked — there's something magical about writing a few lines of code and watching something come to life. After entering the workforce, the scale shifted dramatically: from toy projects to distributed systems serving millions of users, automating manual workflows that used to take entire teams days to complete. That's when I realized coding wasn't just fun — it was powerful.

From Shanghai to California, from startup chaos to Meta open source to building payment infrastructure at Finfare — every step has been driven by the same feeling I had watching that show: I want to build things that matter, and I want to be ridiculously good at it.

CURRENTLY

Building distributed payment systems at Finfare. Looking for my next challenge — ideally a team that cares about system design, code quality, and shipping things that actually work.

Also: trying to finish Software Architecture: The Hard Parts (page 94, don't judge me).

OUTSIDE OF WORK
  • 🍵Tea lover
  • 🎵Lofi hip-hop for focus
  • 🚗Road trips
  • 🏂Snowboarding
  • 🌱Learning to keep plants alive
  • 🎮Occasional Honer of Kings
  • ✈️Exploring national parks
THINGS I BELIEVE IN
  • Simple code > clever code
  • Write the README first
  • Dark mode, always
  • Naming things matters
  • The bug is always a typo
  • Comments are love letters to future-you
WHAT I'M LOOKING FOR

A backend or full-stack role at a team that builds real products, moves thoughtfully, and isn't afraid to refactor. Bonus points if the codebase has tests and someone cares about the on-call rotation.

Open to: distributed systems, fintech, infra, platform engineering.

05 / WRITING (Coming soon!)
Mar 2025
Distributed Systems
How We Cut Deployment Time by 60% with Diff-Based CI/CD
A deep dive into the modular GitHub Actions pipeline I built at Finfare — why diff-based execution matters and how Blue-Green deploys changed our release confidence.
Jan 2025
Java · Redis
Designing a Reliable Cashback Redemption Service from Scratch
Walking through data integrity challenges, NACHA file generation, and S3 encryption pipeline behind our user redemption feature.
Oct 2024
Elasticsearch
Tuning Elasticsearch for E-Commerce Search at Scale
Lessons from building commodity search across 100k+ items — analyzers, shard counts, and field weight strategies for best-match results under load.
Jul 2024
Open Source · OCaml
What I Learned Contributing to a 21k-Star Meta OSS Project
Migrating Facebook's Flow type checker to distributed architecture — functional programming in production and the hidden complexity of parallel job execution.
Apr 2024
AWS · Infrastructure
AWS CDK Diff as a Safety Gate: Preventing Unintended Production Changes
How we introduced infrastructure gating using CDK diff to catch schema and environment drift before it reached production.
Jan 2024
Career
From Jingzhou -> Yichang -> Shanghai -> Silicon Valley: My Path into US Tech
Reflecting on the transition from senior engineer in China to UCI grad student to Meta intern to full-time engineer in the US.
View all posts →

Let's work together.

Open to full-time backend / full-stack engineering roles in the US. Feel free to reach out via email or connect on LinkedIn.