00 · human interface
Sangmin Lee · Full-Stack AI Product & Platform Engineer

Ship products.Scale platforms.Make AI reliable.

I build products end to end, then turn repeated complexity into systems teams can scale.

17+ years across engineering & delivery · 4 products taken 0→1 · 500+ experiments · systems serving millionsOPEN TO SENIOR, STAFF & PRINCIPAL ENGINEERING ROLES
Sangmin's portfolio assistantlocal · grounded
Ask me for evidence about Sangmin's products, platform work, engineering level, or availability.
01 · selected systems

AI products. Frontend platforms. Measured outcomes.

Four systems showing end-to-end ownership, reusable architecture, and measurable product and engineering outcomes.

04 systems · selected proof
open source · developer platform
evidence / 01

OpenSquid

MIT

owned

Designed and published the TypeScript and Node.js package, CLI, MCP runtime, coding-agent integrations, CI/CD, and release gates.

system

Durable context and specification-driven verification constrain coding-agent drift across long-running work.

result

Released as open-source MIT tooling with automated tests and gated publishing.

TypeScriptNode.jsMCPCI/CD
View OpenSquid on GitHub
founder · full-stack AI product
evidence / 02

RankLabs

2–4×

owned

Built the product across controlled LLM querying, crawling, analytics, scoring, deployment, and operations.

system

Connects page-level evidence to model-response drift and AI visibility monitoring.

result

Operates at <10 ms p95 and improved AI mention coverage 2–4× in controlled deployments.

Next.jsTypeScriptLLMsAnalytics
Visit RankLabs
frontend platform · e-signature
evidence / 03

Verdocs UI Platform

cross-framework

owned

Extracted complex e-signature flows into standalone, versioned libraries consumed by multiple applications.

system

Exposed framework-agnostic Web Components through stable APIs for incremental migration.

result

Reduced duplicate implementation and decoupled product flows from any one JavaScript framework.

TypeScriptAngularWeb ComponentsComponent APIs
product platform · anonymized
anonymizedevidence / 04

E-commerce Product-Page System

+17%

owned

Independently upgraded product-page templates and remediated technical SEO issues using RankLabs.

system

Combined product-template changes, structured technical fixes, and measurement across search and tracked LLMs.

result

Within two months, organic traffic rose 17%, tracked LLM visibility improved 43%, and AI referral share grew from 0.1% to 8% of external human sessions.

Product templatesTechnical SEOAnalyticsLLM visibility
02experience

Experience across product and platform.

  • 01
    SAE.SOFull-Stack & Experimentation Engineer (Contract)
    2021-06 – present500+ experiments
  • 02
    Perspecta Labs / Peraton LabsSenior Research Scientist
    2021-01 – 2025-06 · 4 yrs~38% faster
  • 03
    VerdocsSenior Full-Stack Engineer
    2016-12 – 2021-01 · 5 yrscross-framework
  • 04
    Complex NetworksLead Front-End Developer
    2015-09 – 2016-12 · 1 yrmillions / site
  • 05
    Computer PathwaysCo-Founder / IT Consultant
    2008-07 – 2015-03 · 7 yrs6+ years
04contact

Looking for an engineer who can own the product and strengthen the platform?

I am considering Senior, Staff, and Principal roles where I can ship across the stack, improve the frontend platform, and build reliable AI-assisted engineering systems.

direct email · no scheduling gate
start a direct conversation
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