LJY.
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Senior Systems Analyst · Singapore

Lee Jia
Yun.

LEE · JIA · YUN EST.
2000
SG ·
GMT+8

I build end-to-end — backend, frontend, data, deploy — alone, on tight deadlines. Currently shipping a 4-surface Rust platform and a series of Vercel microsites.

Role
Sr. Systems Analyst
+ independent builds
Focus
Solo full-stack
AI-assisted dev
Stack
Rust · Python
TypeScript · Next.js
Contact
Rust · Tauri+ RabbitMQ+ Next.js · React+ FastAPI · Python+ Claude · Codex · Gemini · Hermes · Cursor · Clawdbot+ Multi-agent workflow+ Karpathy method+ Rust · Tauri+ RabbitMQ+ Next.js · React+ FastAPI · Python+ Claude · Codex · Gemini · Hermes · Cursor · Clawdbot+ Multi-agent workflow+ Karpathy method+
01 / About

A business analyst who learned to ship the system.

Profile

Started as a BA — turning ambiguous requirements into something engineers could quote. Now I sit on both sides: gathering the requirement and shipping the code that solves it.

Off-hours I keep that muscle stretched on side projects — a four-surface Rust platform and a recurring practice of small Vercel microsites. Different stacks, same loop: read the problem, name the unknown, ship a thin slice.

My instinct is still analyst-first: a number without a denominator, a window, and a scope isn't a number — it's a guess. The code I write is in service of that.

I like the boring stuff most engineers avoid: reconciling messy reality against a cleaner model, deciding which side wins, and making that decision auditable.

5+
Projects
shipped / in flight
5+
Languages
shipped in
5
Years across
BA + Dev
1×
Engineer
per project
02 / Selected Work

Things I've built — and what's next.

→ 001

Zutt

Rust RabbitMQ 4 apps Multi-agent WIP
Four surfaces · one Rust core · RabbitMQ event bus. Built with paired AI agents in rotation (Claude, Codex, Cursor) — an experiment in how far paired-agent development can be pushed before architecture, not code, is the bottleneck.
▲ 01
HQ
Back-office ops
& reporting
▲ 02
CRM
Customer &
loyalty data
▲ 03
Cashier
Counter terminal
checkout flow
▲ 04
Order
Guest-facing
ordering surface
4 surfaces 1 event bus 100% solo build Rust + paired-agent dev
→ 002

Brand Microsites

Next.js Vercel Motion · Design Series
An ongoing practice of designing and shipping small brand / product microsites on Vercel. Each one is a self-contained exercise in typography, motion, and visual identity — figuring out how to make a tiny site feel inevitable. Latest live: summer-bliss.vercel.app.
3+ live on Vercel Design + ship cycle < 1 week Next.js · TS · Motion
→ 003

Reconciliation Engine

FastAPI React Postgres Azure SSO Case study
Designed a 5-step Excel-vs-system matching algorithm for an internal finance team — per-bank running sums, bucket subtractions, vendor-rule overrides, and per-voucher one-time edits with row-level audit history. Replaced a manual monthly chase with a self-serve workflow. Shipped solo: requirements, backend, frontend, deploy, post-launch support.
Replaces a manual monthly chase Daily-use by finance team Production HTTPS · Azure SSO
→ 004

Enterprise SSO Integration

Azure AD MSAL JWKS React · FastAPI
Wired Azure AD / MSAL across two internal web apps. JWKS verification on the backend, lazy-init Proxy on the frontend to survive plain-http LAN, custom logoutRedirect → clearCache flow to fix the multi-account chooser UX. Email-primary admin lookup so the auth layer doesn't lock itself behind a single AAD signature.
2 apps secured · Azure AD tenant Multi-account chooser fix Same-origin /api · JWKS verified
→ 005

Fabric Semantic Models

Power BI DAX OneLake Python · pyarrow
Built Power BI semantic models and DAX measures over a Dataverse-backed lakehouse on Microsoft Fabric. Wrote local-Python pipelines (azure-identity + pyarrow) to read OneLake parquet directly for joins that curated SQL views couldn't handle. Star-schema design, paginated reports, refresh-aware measures.
Semantic models + paginated reports OneLake-direct joins beyond curated SQL Refresh-aware DAX
03 / Toolbox

The stack I actually reach for.

▲ Languages
Python · TypeScript · Rust · SQL
▲ Backend
FastAPI · Tauri · RabbitMQ · pandas · SQLAlchemy
▲ Frontend
React · Next.js · Vite · Tailwind · shadcn/ui
▲ Data & BI
PostgreSQL · MS SQL · SQLite · Dataverse · Microsoft Fabric · OneLake · Power BI · DAX · M / Power Query
▲ AI agents
Claude · Codex · Gemini · Hermes · Cursor · Clawdbot · (multi-agent over RabbitMQ)
▲ Deploy
nginx · pm2 · Docker · Vercel · Windows Server
▲ Auth
Azure AD · MSAL · JWKS · OAuth 2.0
▲ Workflow
Claude Code · Codex CLI · Cursor · Obsidian · Git
04 / Credentials

Recently certified, verifiable.

Let's talk.