Building an Offline-First Knowledge Hub with Obsidian
A Markdown-first workflow for private notes, public articles, research references, and website publishing.
Backend Engineer · System Builder · AI/NLP Learner
Hi, I'm Vinh.
I build backend systems with .NET, databases, and practical engineering habits. I also study AI, NLP, and write down what I learn through technical articles, research notes, and project case studies.
Currently
What I am exploring now
Backend reliability
Concurrency, transactions, idempotency, inventory flows, and service boundaries.
Systems fundamentals
C++, algorithms, performance, Linux, and the developer workstation as a system.
AI and NLP
Transformers, LoRA/QLoRA, summarization, evaluation, and research workflow.
Featured Articles
Edited technical writing
Longer notes on backend engineering, databases, Linux, and AI concepts.
Understanding Attention Masks in Transformers
Why masks use very negative values before softmax, and how padding and causal masks solve different problems.
FIFO Inventory Deduction and LIFO Stock Return
Designing batch-based stock deduction and reverse stock return with .NET, MySQL, and clear transaction boundaries.
Handling Concurrent Redemption Operations in .NET and MySQL
A practical design note for preventing double state transitions when Reject and Cancel requests race each other.
Selected Projects
Case studies, not badges
Each project focuses on the problem, role, decisions, tradeoffs, and lessons learned.
case-study
LETOS
An e-commerce operations system centered on inventory, order flow, marketplace integration, and backend reliability.
- Role
- Backend engineer
- Stack
- .NET · MySQL · EF Core · Nginx
case-study
VANGIAI
An e-commerce architecture case study covering frontend, backend APIs, database choices, Docker, Nginx, and deployment.
- Role
- Project builder
- Stack
- Next.js · Node.js · MongoDB · Docker · Nginx
active
Vietnamese News Summarization Research
An applied NLP project connecting dataset preparation, model adaptation, evaluation, and engineering workflow.
- Role
- Research and engineering
- Stack
- Python · Transformers · LoRA · QLoRA · FAISS
case-study
Zenpack
A cloud-based logistics and operations platform focused on workflow clarity and integration-heavy backend design.
- Role
- Full-stack/backend contributor
- Stack
- Next.js · .NET · PostgreSQL · Docker
Research
Paper reviews and experiments
Adaptive Prompting for Continual Relation Extraction
A paper-review template for tracking method, datasets, results, limitations, and personal takeaways.
LoRA and QLoRA for Vietnamese News Summarization
A research note for comparing parameter-efficient fine-tuning strategies on Vietnamese summarization datasets.
Recent Notes
Small pieces of a public knowledge base
Pre-Layer Normalization in Transformers
A short note on why moving LayerNorm before attention and feed-forward blocks can improve training stability.
How EF Core Concurrency Tokens Work
A compact note on optimistic concurrency, row versions, and failed updates in EF Core.