J Jules Park
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About

I'm a senior staff engineer with 12 years of experience building backend infrastructure for product-led companies. I work best with small teams (under 8 engineers) on systems that need to be both correct and fast.

I've spent the last six years focused on developer-facing APIs and platform tools. Comfortable across the stack but I do my best work in Go and Rust.

Experience

Senior Staff Engineer

2022 — present

Mercury · Remote (US/EU)

Tech lead on the Banking Platform team. Owned the migration from a monolithic Rails core to event-driven Go services. Built the developer platform that 80% of our partner banks now use.

  • Reduced P99 transaction latency from 380ms to 42ms
  • Led a 6-engineer team through a 14-month re-platforming
  • Authored the company's RFC process — now used across all eng teams

Staff Engineer

2019 — 2022

Stripe · Singapore

Joined the Payments Infrastructure team. Designed the routing layer that picks payment processors per-transaction. Mentored 8 engineers across Singapore and Dublin.

  • Designed and shipped the multi-acquirer routing system (140M+ daily transactions)
  • Created the internal "Why we build it this way" document, since archived as required reading

Senior Engineer

2016 — 2019

Coupang · Seoul

Logistics platform engineer at Korea's largest e-commerce company. Built the order routing and warehouse assignment system.

Engineer

2013 — 2016

Naver · Seoul

First job out of university. Worked on search infrastructure. Learned C++ and Java the hard way.

Education

B.S. Computer Science

2009 — 2013

Seoul National University

Distributed systems concentration. Thesis: "Consistent hashing for graph databases under partition load."

Selected open-source & writing

Talks & press

  • 2025 — Strange Loop · "Six wrong ways to design an API"
  • 2024 — KubeCon EU · "Kubernetes for the 4-engineer team"
  • 2023 — QCon Singapore · "Distributed systems for tiny teams"
  • 2023 — Featured · Increment Magazine · Issue 16

References

Available on request — happy to introduce you to past managers and reports.