Full-stack payments by day · multi-agent LLM systems by night

Hi, I'm Kelvin You
AI-native Full-stack Engineer · Fintech Payments & Agent Systems

0+Years Exp.
0+Projects

About Me

Learn more about my journey and what drives me as a developer

Start with a messy, ambiguous problem

Design it into a system, not a patch

Ship it so it runs on its own

How I Work

I chase the pattern under a mess — an ambiguous problem, a slow system, a manual workflow — and turn it into something that runs on its own.

Currently Building

A multi-agent stock-analysis pipeline on the Claude Agent SDK — four analyst agents, a debate stage, and an outcome-memory loop that scores its own past calls.

TypeScriptNext.jsReactPythonClaude Agent SDKMCPFastAPIPostgreSQL

Skills

Grouped by how far each one has actually gone — not by category. A reader already knows PostgreSQL is a database; what a list can't say is whether it ever carried a paying customer.

Shipped to users

  • TypeScript
  • React
  • React Native
  • Kotlin
  • Next.js
  • GraphQL
  • Apollo Client
  • PostgreSQL
  • Supabase
  • Vercel
  • Git

dtcpay payments platform, 9,000+ users · Simpletruss · PTIB, paid for by 3 centres

Running in my own systems

  • Python
  • Node.js
  • FastAPI
  • LLM Integration (Claude API)
  • Claude Agent SDK
  • MCP (Model Context Protocol)
  • Multi-agent Systems
  • RAG
  • Prompt Engineering
  • Docker
  • GitHub Actions (CI/CD)
  • Claude Code
  • Playwright

Personal-OS · ai-stock-analysis — public repos, on a weekly cadence, no paying users

Coursework only

  • Java
  • Solidity
  • Flutter
  • Dask
  • Firebase

2022–23 capstone and university assignments · nothing since

Studied, never shipped

  • Go
  • Redis
  • AWS
  • Kubernetes

Current learning target · listed here rather than padded into the rows above

Projects

Each one with the measured result it produced — and an honest blank where there isn't one.

Agentic systems2026

Multi-Agent Stock Analysis

Four analyst desks — fundamentals, technical, sentiment, macro — each on its own MCP server, argued through a debate stage and merged by a synthesizer. Signals are validated walk-forward against a frozen holdout, with Wilson intervals and a deflated Sharpe on the strategy search — which is how I know the factor still lagged buy-and-hold.

Python · Claude Agent SDK · MCP · RAG · Multi-agent Systems · Walk-forward Backtesting · Pydantic · FastAPI

1.32
Sharpe on a frozen 2023-26 holdout, net of cost
10/12
tickers still net-positive at 30 bps/side
Source

2026

Personal-OS

Guardrail design over raw model output. Only an acute bad-sleep night is non-overridable; on the noisier 7-day trend, live HRV overrides the automated deload — so it catches real risk without crying wolf every week on a lagging metric.

Claude Code · MCP · LLM Integration · Multi-agent Systems · Python · TypeScript · Agent Skills

12
agent skills running on a weekly cadence
1
non-overridable rule; the rest defer to live HRV
Source

2025

PTIB

Multi-tenant SaaS that digitised a 200-student tuition centre: role-based portals, Stripe billing, QR attendance, row-level security in Supabase.

Next.js · TailwindCSS · Supabase · PostgreSQL · Stripe · Shadcn · React

$500
MRR from 3 pilot centres
5 hrs
of admin saved per week
Demo
All 7 projects

Experience

From production fintech platforms to agentic systems I build on my own time.

2025

NOW

1 yr 1 mo

Full-timeKuala Lumpur, Malaysia

Frontend Engineer

DTCPay (FinTech)

Production payments platform, 9,000+ users. Led Flutter to React Native migration unifying mobile + web.

  • Kotlin backend for cross-currency batch payments: FX quote lock, largest-remainder allocation, CAS-on-status duplicate guard.
  • Fail-closed PII masking across 5 payment surfaces — unmask only on explicit corporate classification.
  • KYT case review UI: maker-checker approval workflow, RFI state machine, scope-gated decisions.

Kotlin · React · React Native · TypeScript · Payment Systems · Concurrency · System Design · Fintech

Wrote about this

/cas-instead-of-idempotency-key/conserving-money-across-rows

2024

2025

1 yr 1 mo

Full-timeKuala Lumpur, Malaysia

Frontend Engineer

Simpletruss

Building enterprise property management SaaS. 500+ properties, 10K+ maintenance tickets monthly.

  • Component library with compound patterns, TypeScript generics, Storybook docs. 40% faster dev velocity, 60KB bundle reduction.
  • GraphQL layer: Apollo Client, 80% cache hit rate, custom hooks (usePaginatedQuery, useOptimisticMutation). Type-safe, zero prop-drilling.
  • Performance: Code splitting, virtualization for 10K+ rows, Zustand over Redux. 35% faster initial loads.

React · TypeScript · GraphQL · Apollo Client · Zustand · Material UI · Storybook

LessenPro

Demo

Scheduling engine, vendor coordination, maintenance tracking. 500+ properties managed.

React · TypeScript · GraphQL · Material UI · Apollo Client

2023

2024

10 mos

Full-timeKuala Lumpur, Malaysia

Frontend Developer

Beyondsoft (Tencent)

Analytics platform for Tencent, MiHoYo (Genshin Impact), major game studios. Millions of events/day.

  • Performance: Virtual scrolling (500K rows), Web Workers for parsing, debounced filters. Sub-3s loads at 60fps.
  • Quality: Jest standards, mandatory reviews, 40% fewer production bugs. Docker dev env: 4h → 30min onboarding.
  • Cross-team: Specs with Tencent engineers, cross-browser (Safari, IE11), China CDN optimization.

React · TypeScript · Redux · Ant Design · Jest · Docker · Webpack · Go

Databrain Global

Demo

Real-time player analytics. 100K+ row datasets, complex filters, interactive dashboards.

React · Umi.js · Ant Design · TypeScript · Go

Wrote about this

/beyondsoft

2023

2023

6 mos

InternshipKuala Lumpur, Malaysia

Java Engineer Intern

Finexus (Fintech)

First exposure to fintech production payment systems — legacy Java/JSP monolith, thousands of daily transactions. Foundation for current fintech work at dtcpay.

  • Fixed connection pool bug causing peak-hour failures. HikariCP + JMX monitoring → 99.9% uptime.
  • Deployment automation: Bash scripts for Tomcat WAR deploys. 4h → 2h per release.
  • Jasper Reports: Query optimization, indexing. 8s → 1.2s report generation.

Java · Oracle SQL · Servlets · JSP · Tomcat · Shell Scripting · Jasper Reports

2020

2021

4 mos

InternshipKuala Lumpur, Malaysia

Blockchain Engineer Intern

Techtics (Web3)

Ethereum dApp during 2020 DeFi boom. Smart contracts, gas optimization, MetaMask.

  • Solidity contracts: Reentrancy guards, gas estimation UI, MetaMask signing. Deployed to mainnet.
  • Gas optimization: IPFS storage, batched transactions. 65K → 38K gas (40% savings).

React · TypeScript · Solidity · MetaMask · Node.js · Express · Redux

Education

Two credentials, one institution, four unbroken years. Certificates and transcripts are on file.

Tunku Abdul Rahman University of Management and Technology

Kuala Lumpur, Malaysia2019 – 20234 yrs 2 mos unbroken

3.72

CGPA

Dean's List

top 10% of cohort

CertificateTranscript

Bachelor (Hons)2021 – 2023

Software Engineering (Honours)

Distributed systems, parallel computing and performance optimization, carried through 15+ builds — blockchain dApps, mobile apps, graphics.

  • Final year project — a travel guide app — presented to 50+ industry professionals
  • Led a capstone team of 4
  • Earned the Databrain Global (Beyondsoft) internship on university recommendation
Core
Data Structures & Algorithms · Distributed Systems · Parallel Computing · Human-Computer Interaction · Graphics Programming
Electives
Mobile Development (Flutter) · Blockchain Development (Solidity) · Data Science (Python)

3.7439

CGPA

Transcript

Diploma2019 – 2021

Computer Science

Where the fundamentals came from: object-oriented Java, then down to C and assembly, against a full mathematics track.

Core
Object-Oriented Programming (Java) · C & Assembly · Algebra · Calculus · Statistics · Discrete Mathematics
Kuala Lumpur · GMT+8Replies within a dayOpen to conversations

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Hi Kelvin — we're hiring a full-stack engineer and your payments work looks like a fit. Here's the team and the scope —

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