Currently working on
Outsourced CRM systems serving 5K – 10K users — finance, accounting, payments, and MLM commission engines.
Le Truc · Full-Stack Developer
Building thoughtful software for real-world business problems.
I'm Le Truc (letrucdev) — a Full-Stack Developer who has shipped CRM systems serving 5K – 10K users. I work across React, Next.js, NestJS, Laravel, and .NET Core, and I care about clean architecture, performance, and the business problem behind the code.
Hoan Kiem, Vietnam
letruc.ts
1const letruc = {
2 role: "Full-Stack Developer",
3 location: "Hoan Kiem, Vietnam",
4 currentFocus: [
5 "CRM Systems",
6 "Scalable Web Apps",
7 "Clean Architecture",
8 ],
9 experience: {
10 frontend: ["React", "Next.js"],
11 backend: ["NestJS", "Laravel", ".NET Core"],
12 database: ["MySQL"],
13 tools: ["Git", "GitHub"],
14 },
15 projectsDelivered: 2,
16 usersServed: "5K - 10K",
17 motto: "Code with purpose, ship with confidence",
18};
About me
A Full-Stack Developer who treats clean code as a tool, not a goal.
I'm passionate about clean code, clear architecture, and performance optimization. Solving real business problems is more fun than chasing trends.
Currently learning
Angular, CI/CD workflows, and Proxmox for homelab and virtualization experiments.
Next goals
System design, microservices, and cloud-native architecture — moving from product to platform thinking.
Tech I work with
The tools behind real-world systems serving 5K – 10K users.
From frontend frameworks and backend runtimes to caching, realtime layers, and the infrastructure that ties it all together.
Languages
TypeScript
JavaScript
PHP
C#
HTML5
CSS3
Frontend
React
Next.js
Redux
Tailwind CSS
Backend
NestJS
Laravel
.NET Core
Node.js
Database & Cache
MySQL
Redis
Realtime
Socket.IO
WebSocket
Tools & Workflow
Git
GitHub
VS Code
Postman
DevOps & Infrastructure
Docker
Nginx
Reverse Proxy
Load Balancing
Networking
Currently learning
Angular
GitHub Actions
GitLab CI
Proxmox
Featured projects
Two outsourced CRM systems, shipped end-to-end.
Both projects below are outsourced under client contracts. Due to NDA terms, I cannot publicly share source code, client names, screenshots, or specific technical details — what follows is a high-level overview of scope and role.
Project 01
Account Management Platform — Multi-Role Transaction & Banking System
A multi-role account management platform (User, Admin, Super Admin, Cashier) built on a microservices architecture — one FastAPI backend serving four isolated Next.js frontends, packaged with Docker Compose. Built Oct 2023 – May 2024 and delivered to the client.
Delivered May 2024Oct 2023 – May 202410K+ users4 frontends, 1 backendOutsourceFrontend Lead 100%NDA — Confidential
Key features
- Four isolated Next.js frontends — one per role (User, Admin, Super Admin, Cashier) — for smaller bundles and per-role access isolation
- Multi-role authentication with JWT access + refresh token flow and Axios interceptor token refresh
- 2FA (TOTP) on the admin frontends — QR enrollment and code verification
- VietQR bank-transfer QR generation for the deposit flow
- Bank, transaction, and balance management — deposits, withdrawals, approval workflow, and ledger history
- Game transaction & activity history with per-user audit logging
- Realtime notifications via WebSocket + Socket.IO with room-based broadcast per user / agent
- CSV export with papaparse and form validation with React Hook Form + Yup
My role
- Built all four Next.js + TypeScript frontends from scratch — architecture, Material-UI customization, and end-to-end business flows
- Integrated TanStack Query for data fetching/caching, React Hook Form + Yup for validation, and an Axios interceptor for JWT refresh
- Implemented 2FA TOTP enrollment, VietQR transfer QR generation, and Socket.IO realtime notifications on the client
- Worked directly with the client — gathered requirements and translated business rules into per-role UI flows
- Coordinated tightly with the FastAPI backend team on API contracts, schemas, and error/response shapes
- Contributed to the role-permission model design (User / Admin / Super Admin / Cashier) so the frontends matched the business logic
Tech stack
Next.jsTypeScriptFastAPIMySQLRedisSocket.IODocker
Source code and client details are not publicly available due to contractual obligations.
Project 02
Multi-App Account Platform — Four Next.js Frontends + Realtime Gateway
A second outsourced platform built as four isolated Next.js 14 (App Router) frontends — User, Admin, Super-Admin, and Game Admin — backed by a FastAPI core API, a PHP/WordPress MLM commission module, a Socket.IO realtime gateway, and shared MySQL/Redis, all orchestrated with Docker Compose. Built Aug 2024 – Feb 2025 and delivered to the client.
Delivered Feb 2025Aug 2024 – Feb 20255K+ users4 frontends + realtime gatewayOutsourceFrontend Lead 100%NDA — Confidential
Key features
- Four isolated Next.js 14 (App Router) frontends — User, Admin, Super-Admin, Game Admin — for smaller bundles and per-role access isolation
- Multi-role authentication with JWT access + refresh and MFA via TOTP (QR enrollment + code verification) on the admin tiers
- User flows: deposit, withdrawal, transactions history, game catalog & detail, affiliate/MLM with referral-tree map, realtime notification center, profile
- Admin flows: user management (active/block, KYC verification requests), deposit/withdrawal approval, revenue and transaction reporting
- Super-Admin flows: admin manager, game manager, exchange-rate and Binance price-source management, MLM commission policy, theme & metakey manager, system statistics
- Game Admin console: room list, session/round configuration, game configuration, system settings
- Realtime notifications over Socket.IO — JWT-authenticated handshake, per-user and per-role rooms, transactional and custom push events with REST companion endpoints
- EN/VI internationalization with next-intl, dark mode with next-themes, dashboards via recharts, MLM tree via react-organizational-chart
- Redis (ioredis) for shared session and hot-data cache; full stack packaged with Docker Compose (4 frontends + FastAPI backend + PHP/WordPress MLM service + socket gateway + Redis + MySQL)
My role
- Owned 100% of the frontend across all four Next.js + TypeScript apps — architecture, shared UI on Tailwind + Radix/shadcn-ui, data layer with TanStack Query/Table, Axios HTTP client
- Implemented JWT access/refresh with Axios interceptors and the TOTP MFA enrollment flow (QR + OTP verification) on the admin tiers
- Built the Socket.IO client — JWT handshake, auto-reconnect strategy, room-aware event handling for per-user/per-role push
- Built i18n (EN/VI) with next-intl, the MLM referral tree with react-organizational-chart, and dashboards/charts with recharts
- Designed component architecture and performance budget for systems serving 5K+ concurrent users
- Worked directly with the client to translate business rules across User / Admin / Super-Admin / Game-Admin tiers and finalize UI/UX
- Collaborated with the Python (FastAPI) backend team on the core API and with the PHP/WordPress team on the MLM commission module — aligning on contracts, schemas, and event payloads
Tech stack
Next.jsTypeScriptTailwind CSSFastAPIWordPress APIPHPMySQLRedisSocket.IODocker
Source code and client details are not publicly available due to contractual obligations.
Want to know more about architecture, performance handling, or payment integration? Reach out and I'll share whatever the NDA permits.
Milestones & lessons learned
A real-world classroom — and a financial first.
$15,000+
Earned from outsourced projects
20
Age
2
Projects shipped
“These two CRM projects weren't just a financial milestone — they've been my biggest real-world classroom so far.”
What I learned
Frontend mastery
- Deeper grasp of Next.js — SSR, ISR, App Router, performance optimization.
- State management for complex systems with dozens of modules.
- UI/UX thinking when working directly with clients — translating business needs into interfaces.
Docker & DevOps
- Containerizing Next.js apps and packaging consistent dev/staging/production environments.
- Writing Dockerfiles and docker-compose for multi-service stacks (Next.js + FastAPI + WordPress + MySQL).
- Image layering, multi-stage builds, and image-size optimization.
Networking & infrastructure
- Reverse Proxy with Nginx — routing multiple services under one domain, SSL termination.
- Load balancing for systems with high concurrent user load.
- Networking fundamentals — DNS, ports, internal container networking, firewall rules.
- Configuring rate limiting, CORS, and security headers at the proxy layer.
Soft skills gained
Client communicationCross-team collaborationDeadline managementSystems thinking
Let's talk
Have a system that needs a thoughtful frontend?
I'm open to outsourced frontend work, full-stack collaborations, and freelance engagements — particularly for CRM, finance, and high-concurrency systems.