Available for opportunities

> Hello, I'mKai_

9+ years building high-scale distributed systems for gaming and payment platforms. Currently owning 8 production systems serving 3 brands.

kai@portfolio ~ /stats
$ cat profile.json
{
  "name": "Lương Nhật Kha",
  "alias": "Kai",
  "role": "Tech Lead",
  "experience": "9+ years",
  "systems_owned": 8,
  "total_loc": "160K+",
  "payment_integrations": "40+"
}
$./check-status.sh
API:connecting
Latency:0ms
Uptime:99.9%
WS:standby
160K+
Lines of Code
9+
Years Experience
160K+
Lines of Code
8
Systems Owned
40+
Integrations
scroll down
./projects

Production Systems

Battle-tested systems handling payments, fraud detection, and gaming operations at scale

Processor Pattern
Java 8Mario3

Payment Gateway

High-throughput payment processing system handling millions of transactions with 40+ third-party integrations

Request
Router
Processor
Provider
0
Lines of Code
0+
Integrations
0K+
Daily Transactions
View Architecture
Clean Architecture
Java 21Spring Boot 3.5

Platform API Gateway

Central API gateway serving all internal tools with RBAC, multi-auth, and Jira approval workflows

Controller
UseCase
Domain
Infra
Clean Architecture Layers
0+
API Handlers
0
Source Files
0
Auth Methods
View Architecture
Either Monad
Java 21Spring Boot 3.2

Automated Slip Processing

Intelligent withdrawal approval system with 17-rule validation engine and fraud detection

1
2
3
4
5
...17 rules
0+
Validation Rules
0%
Auto-Approval Rate
0K+
Daily Slips
View Architecture

More Systems

6
Kafka Topics

Real-time Fraud Detection

Multi-signal fraud detection consuming 6 Kafka topics

Java 21KafkaMongoDB
56+
Commands

Gaming Administration

56+ admin commands for user and gaming operations

Java 8MongoDBHazelcast
3
Brands

Multi-Brand Dashboard

React admin dashboard serving 3 brands with feature flags

React 17TypeScriptRxJS
Full
Stack

Content Management System

Full-stack CMS with React 19 + NestJS 11

React 19NestJS 11Prisma
ILM
Hot/Warm/Cold

Audit Logging System

Centralized audit logging with Elasticsearch ILM

Java 21ElasticsearchKafka
./skills

Technical Expertise

9+ years of hands-on experience with modern technologies

Backend

Java 2195%
Spring Boot 3.x95%
NestJS85%
gRPC/Protobuf85%
Kafka90%
Python70%

Frontend

React 1990%
TypeScript90%
Next.js 1585%
Tailwind CSS85%

Database

MongoDB90%
MySQL85%
Elasticsearch85%
Redis80%
ClickHouse75%

DevOps

Docker80%
Kubernetes70%
GitHub Actions80%
AWS75%

Also experienced with

RabbitMQHazelcastPrismagRPCProtocol BuffersWebSocketAnt DesignTailwindWebpackViteJestJUnitGitLinuxNginx
./contact

Let's Connect

I'm always open to discussing new opportunities, interesting projects, or just having a chat about technology.

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