Software Engineer · Web Architecture · Singapore

Hi, I'm John 👋

I build software that is user-friendly and beautiful.

I'm a software engineer with 7 years of experience in web architecture and development — currently at TikTok Singapore, previously at LINE Taiwan. I'm strongest at large-scale product engineering and performance, and I enjoy explaining complex problems in simple terms. This is where I keep my technical notes, the projects I've built, and how I like to work.

John Hsieh

John Hsieh · 謝謂中

Singapore

TikTok SingaporeLINE Taiwan

Now

Building financial settlement systems for ad delivery on the User Growth team at TikTok Singapore

years in software engineering
7+years in software engineering
products shipped end-to-end
20products shipped end-to-end
working languages: ZH · EN · JA
3working languages: ZH · EN · JA
weekly Chrome users of my browser extension
10,000+weekly Chrome users of my browser extension

Who I am

I'm John Hsieh (謝謂中), a software engineer who believes in putting user experience first.

I'm a software engineer with seven years of experience specializing in web architecture design and development, and I've worked as a Senior Software Engineer at TikTok Singapore and LINE Taiwan. My strongest areas are large-scale product engineering, web architecture, and performance optimization, with hands-on cross-stack delivery (Node.js BFF / GraphQL, Go, LLM integration). My go-to stack is React (Next.js), Vue (Nuxt.js), and TypeScript.

I've worked at large software companies with thousands of employees, writing high-caliber code within well-established tools and processes. I've also helped early-stage startups plan their frontend architecture from scratch and take products all the way to launch.

I speak Mandarin, English, and Japanese, and I'm well-versed in Agile development and sustainable team delivery. I enjoy collaborating with others and communicating with non-technical stakeholders.

What I value

01

User experience first

My mission isn't just to build a product, but to build software that is user-friendly and beautiful. Studying user behavior with A/B tests and heatmaps as a digital ad specialist gave me a strong UI/UX foundation.

02

Spot problems early

I don't just wait for requirements. I look for patterns in user feedback and start technical work on my own — at TikTok I twice spotted risks during development and got fixes out in under 3 days, stopping production incidents before they happened.

03

Plan within limits, build with rigor

Startups taught me to plan and adapt with limited resources; large companies taught me the rigor of "every line gets reviewed before it's merged."

04

Share, and grow the team

Seeing someone grow because of my help is as rewarding as solving a hard technical problem. I mentored 2 new engineers at LINE, led an internal Next.js course, and brought Scrum and retrospectives to my team at TikTok.

Experience

From Japanese-market sales to software engineering — I've worked at companies with thousands of employees and helped startups build products from scratch.

  1. TikTok Singapore

    2024.11 – Present

    Software Engineer · Singapore

    On the User Growth team I build the financial settlement systems for ad delivery — a frontend microservices system on React, a monorepo, and an in-house framework — and use AI-assisted development to ship full-stack features across TypeScript and Go.

    • Introduced Web Worker multi-threaded validation, cutting UI blocking from large CSV validation by 90% and the TBT of large-form initial rendering by 98%
    • Optimized a production de-duplication monitor script — one of our production monitoring mechanisms — with partitioning, heaps, and file streaming — dozens of times faster, with space complexity reduced from O(n²) to O(n)
    • Caught two risks during development and escalated them myself; fixes shipped in under 3 days with zero related on-call tickets
    • About 30% of my working time goes to handling production on-call
    • Led the team in adopting Scrum, using retrospectives and refinement to build self-correction and backup across the team
  2. LINE Taiwan

    2021.08 – 2024.10· 3 yrs 3 mo

    Software Engineer · Taipei, Taiwan

    Built LINE Shopping on a ~60-person EC team (Vue SSR + GraphQL + TypeScript), led a 4-person team rebuilding the CMS back office, and joined the JavaScript Task Force that set company-wide frontend guidelines.

    • Independently researched, designed, and built the "Live Shopping" video auto-play module (dual IntersectionObservers + Vuex + HLS.js)
    • Led a 4-person team rebuilding the PHP-based CMS in Next.js, separating frontend and backend in about a year while integrating seamlessly with the legacy system
    • Mentored 2 new engineers and led an internal Next.js teaching forum
    • Introduced Lighthouse CI and made it part of the standard development workflow
    VueNext.jsGraphQLNode.jsTypeScriptAuto-Play on Scroll — Live Stream List
  3. AI.Book

    2021.09 – 2024.10· 3 yrs 2 mo

    Software Engineer (Contract) · Remote

    Sole technical owner of an online photo book platform. Joined at an early stage, made the tech selection and architecture decisions myself, and communicated directly with the company's non-technical head.

    • Built the core online photo book editor alone, from zero to launch in 6 months (Vue + Nuxt.js)
    • Led the backend API design: AWS Cognito OAuth2 sign-in, the cart and order flow, and payment result integration
    VueNuxt.jsAWS Cognito
  4. FundFluent

    2021.01 – 2021.09· 9 mo

    Software Engineer (Contract) · Remote

    A Hong Kong SME lending startup. Frontend technical lead from the founding stage, planning the frontend architecture and tech selection from scratch and communicating directly with the company's non-technical head.

    • Independently built multiple frontend systems — UI Kit, SME Portal, and Partner Portal (React / Next.js + TypeScript)
    • Built a cross-project UI component library with Web Components (Stencil.js), published to a private NPM registry
    ReactNext.jsStencil.jsTailwindCSS
  5. Foxit Software

    2020.12 – 2021.08· 9 mo

    Fullstack Engineer · Taipei, Taiwan

    Fullstack engineer on Foxit's newly formed AI team, managing a 2-person frontend team.

    • Planned an n8n-like SaaS automation platform from scratch, combining PDF services (conversion, translation, editing, signing) with various triggers
    • Frontend on Next.js + TypeScript; backend on NestJS + GraphQL + MongoDB + Redis
    Next.jsNestJSGraphQLMongoDB
  6. Aotter Inc.

    2019.08 – 2020.11· 1 yr 4 mo

    Frontend Engineer · Taipei, Taiwan

    Worked on multiple client projects building web apps and ad platforms, in small, fast-paced, project-oriented teams.

    • Main stack: the Nuxt ecosystem + TypeScript + Sass & TailwindCSS, with CI/CD on Docker + K8s
    • Built a small TailwindCSS UI framework for each project to match the designs, with a focus on reusable modules
    Nuxt.jsVueTypeScriptTailwindCSS
  7. 第三緯度 Inc.

    2019.04 – 2019.06· 3 mo

    Frontend Developer · Taiwan

    A frontend-backend separated architecture (Vue + PHP) with WeChat Pay integration. A very short stint.

    VuePHP
  8. Asian Bridge Inc.

    2017.12 – 2019.03· 1 yr 4 mo

    Digital Ad Specialist → Frontend Developer · Taipei, Taiwan

    A Japanese trading company where Japanese was the main working language, and I served as the Japanese-speaking marketing liaison. Started as a digital ad specialist, then transferred internally to frontend development.

    • Researched UI/UX with A/B testing, heatmaps, and Google Analytics to reduce bounce rate and design more intuitive flows
    • As a frontend developer, built official websites and campaign pages while also acting as PM and leading a 2-person frontend team
    • Won the first internal evaluation (August 2018)
    JavaScriptjQueryUI/UX
  9. AsiaYo Inc.

    2016.09 – 2017.09· 1 yr 1 mo

    Japanese Sales & Operations · Taipei, Taiwan

    Brought Japanese B&Bs and share houses onto the platform, and served as the Japanese-business contact and emergency support for travelers in Japan.

    • Jan–Sep 2017: 2,616 listings (93% of target) and 8,846 bookings — 276% growth over the previous year
    JapaneseSales

Education

  • Soochow University

    B.A. in Japanese Language and Literature

    2013 – 2017

  • Doshisha University, Kyoto

    Exchange program · Japanese language & culture

    2016.03 – 2016.08

Languages

  • MandarinNative
  • JapaneseBusiness level · JLPT N1
  • EnglishFluent professional

Outside of work

  • A bit reserved at first, but quite chatty once comfortable — I enjoy talking with people who are just as chatty.
  • I like watching movies, riding motorcycles, gaming, and fixing electronics.
  • Proudest moment: teaching myself to solder so I could fix a trash can.
  • I've tutored 3 frontend students and 1 Japanese language student.

Want to chat?

Whether it's a job opportunity, a technical discussion, or just saying hi — feel free to reach out.

Get in touch