Available for new opportunities

Hi, I'm

Bao Trong

3+ years building scalable web systems with NestJS, Node.js & TypeScript. Expert in RESTful APIs, PostgreSQL optimization, Docker CI/CD, and event-driven architectures.

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Contributed to

Working at Softermii · Replies within 24h

Available for new opportunities

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01—About Me

Backend engineer by day, production firefighter by night.

Fullstack engineer with 3+ years shipping production systems end to end — from domain modelling and API design in NestJS to the React front ends that consume them. I build systems that stay fast and predictable in production: well-indexed PostgreSQL, deliberate Redis caching, and reproducible Docker CI/CD pipelines.

Le Van Bao Trong

Fullstack Developer

Location: Hanoi, Vietnam
Current focus: Microservices & event-driven architecture

01
Backend architecture
NestJS modular monoliths with DDD/CQRS, transactional outbox and BullMQ background workers.
02
Performance at scale
Cut API latency by 30% with Redis caching and query tuning; scaled data ingestion from 10k to 40k records/day.
03
Open source
Merged fixes into socket.io, the Prometheus Node.js client, NestJS Schedule and Fastify.

Years of experience: 3+
Projects delivered: 20+
Happy clients: 10+
Faster API responses: 30%
Merged OSS pull requests: 5

02—Experience

Six roles. Three years. One craft.

From a university MiniApp to healthcare and enterprise platforms — every chapter added scale, ownership and a sharper eye for production.

Mar 2026 - Present
Full Stack Developer
Softermii
Building a cardio platform that enhances heart signal data from medical devices and provides doctors with a convenient interface to process cardio health information, using React.js and Node.js (NestJS) with TypeScript.
- Developed infinite charts for cardio graphs with efficient rendering of large medical data files
- Built event detection and visualization system directly on cardio charts for real-time analysis
React.js · NestJS · TypeScript · PostgreSQL · AWS
Dec 2025 - Present
Fullstack Developer
Vitech Group
Building enterprise CRM/HRM systems and cross-platform marketing automation software using Electron. Specialized in third-party API integrations for social platforms and marketing tools.
- Developed comprehensive CRM system with customer management, sales pipeline, and analytics
- Built HRM platform handling employee records, attendance, payroll, and performance tracking
Electron · React · NestJS · TypeScript · PostgreSQL
Jul 2025 - Dec 2025
Fullstack Developer
Hecatech Vietnam
Developed scalable internal platforms using NestJS (Modular Monolith + Microservice-ready structure) and Next.js, applying Domain-Driven Design (DDD) principles.
- Increased data collection throughput by 300% (from 10k to 40k records/day)
- Cut down manual data entry time by ~20 hours/week through automation
NestJS · Next.js · Redis · MinIO · Docker · GitHub Actions
Feb 2025 - Jul 2025
Fullstack Developer
Hanoi National University of Education
Designed and developed custom software solutions for academic administration using Flutter (Mobile) and React (Web). Built robust backends with PostgreSQL.
- Delivered scalable e-learning systems aligned with Ministry of Education standards
- Improved system accessibility and learning efficiency for faculty and students
Flutter · React · PostgreSQL · Docker
Jun 2023 - Feb 2025
Fullstack Developer
Thuy Loi University
Developed a comprehensive event attendance MiniApp integrated into the Zalo ecosystem using React, TypeScript, and ZMP SDK.
- Implemented Websockets handling 500+ concurrent connections with sub-100ms latency
- Led a team of 5 developers, managing source code via Git
React · TypeScript · Express.js · MongoDB · WebSocket
Jan 2023 - Present
Software Developer
Freelance
Working with various clients from Japan, Singapore, Vietnam across E-commerce, Logistics, and Healthcare industries.
- Optimized PostgreSQL/MSSQL handling 1M+ records, reducing query time by 40%
- Designed secure RESTful and GraphQL APIs with Payment Gateway integration
NestJS · .NET · PostgreSQL · MSSQL · GraphQL · Docker

03—Projects

Built in the open.

A production-grade boilerplate I maintain, and fixes merged into libraries the Node.js ecosystem runs on.

Case study

nestjs-fastify-nx

Most NestJS starters stop at hello-world plus auth, so every new service re-implements the same production plumbing: auth across protocols, background jobs, observability and a hardened release pipeline.

Four runnable services in one Nx workspace, integration-tested against real PostgreSQL and Redis with Testcontainers.

Stars: 12
Forks: 5
Commits: 201

View repository

Key decisions

01DDD + CQRS bounded contexts with Nx module-boundary rules, so cross-context imports fail in CI instead of code review.
02One Fastify instance serving REST/OpenAPI, GraphQL (Mercurius) and Socket.io, sharing Better Auth cookie sessions and Redis pub/sub for horizontal scale.
03A transactional outbox feeding BullMQ workers, so domain events survive crashes.
04A five-layer supply-chain gate — Gitleaks, OSV-Scanner, Semgrep, Trivy and Cosign keyless signing — locally and in CI.

Open Source Contributions

Merged pull requests to widely used open-source projects

GitHub

#2344 fix(cron): do not resurrect a deleted job after its initialDelay elapses

Deleting a cron job during its initialDelay window resurrected it, and a same-name replacement ran in parallel. The timer now starts only the exact instance still registered.

+76 −1Merged Sep 14, 2026View pull request

04—Skills & Technologies

The system I build with.

Not a list of buzzwords — where each tool sits in a production system, and where I have actually used it.

Let's Build Something Together

Have a project in mind or want to discuss opportunities? I'm always open to interesting conversations and new challenges.

Email

levanbaotrong03@gmail.com

Connect with me

Currently Available

I'm open to new opportunities and interesting projects. Let's talk!

Backend engineer by day, production firefighter by night.

Bao Trong

Backend engineer by day, production firefighter by night.

Backend architecture

Performance at scale

Open source

Six roles. Three years. One craft.

Full Stack Developer

Fullstack Developer

Fullstack Developer

Fullstack Developer

Fullstack Developer

Software Developer