Vũ Văn HảiFull-stack · AI-native
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HELLO, I'M

VuVanHai

Full-stack Developer | AI-native development

Software built around the way your business works.

From AI agent teams and workflow automation to CRMs, customer portals and content platforms, I turn business requirements into complete products. I work with you to define the scope, organize development and bring the system into use.

Discuss a projectExplore my workView CV
A team of 10+ AI agentsSystems thinkingDevelopment and operation
Portrait of Vu Van Hai
10+AI agents coordinated
From design to
Operation

WHAT WE CAN BUILD

What does your business need?

I develop new products and extend existing systems, with a scope shaped around your needs.

AI agent teams for your business

Build an AI agent team around your business workflows. I define agent roles and connect your data and tools so agents can work together to find information, carry out tasks and automate processes.

Discuss your needs

Websites & content platforms

Business websites, video libraries, information portals and publishing tools that help your team create, organize and share content.

Discuss your needs

Business & management systems

Connect registration, payments, invoicing and customer service, with customer portals and CRM tools for day-to-day operations.

Discuss your needs

PRODUCTS IN USE

From a practical need to a connected system.

Personal products, freelance projects and business systems I have helped develop. Each case explains what the product does and the work I owned.

PRODUCT JOURNEY
  1. Make a request
  2. Find and act
  3. Get the result

Open-source AI agent (MIT)

Zalo Agent (AI assistant inside Zalo)

Find information in documents, remember details, schedule reminders and create files in chat, with a dashboard for the operator.

  • Document search
  • Reminders
  • File creation
  • Agent management

My role: Creator of zalo-agent, responsible for development and self-hosted deployment.

Source code

Open-source AI agent (MIT)

Zalo Agent (AI assistant inside Zalo)

An AI assistant in Zalo that combines conversation with information retrieval and task execution. Operators configure the assistant, choose its tools and review its actions.

My role:

Creator of zalo-agent, responsible for development and self-hosted deployment.

What does the product do?

Find information

Add documents to a knowledge base that the assistant can search when answering.

Remember and remind

Save useful information and schedule tasks from the conversation.

Carry out tasks

Create Word and Excel files and use the tools enabled for the account.

Manage activity

Configure multiple accounts, limit tool permissions and inspect each run in the dashboard.

How do the parts work together?

Users can retrieve information and carry out tasks through a familiar messaging interface. Available capabilities depend on the Zalo account type and the enabled tools.

Explore the technical details
  • A custom agent loop with RAG and MCP integrations, tool-permission controls and layered prompt-injection defenses.
  • Real-model behavioral evaluations and per-step traces for investigating failures.
  • Supports personal accounts and the official Bot API, with different tool capabilities on each channel.
TypeScriptVercel AI SDKRAGMCP
Source code
PRODUCT JOURNEY
  1. Select text
  2. Read translation
  3. Keep reading

Personal product · Chrome Extension

AI Translator

Translate while reading a web page: hover, select text or use the right-click menu. Supports more than 50 languages.

  • In-page translation
  • 50+ languages
  • Preferences
  • Chrome Web Store

My role: The extension, backend, landing page and Chrome Web Store release.

Chrome Web Store

Personal product · Chrome Extension

AI Translator

A translation extension with different interactions for a quick lookup or a selected passage. The product is published on the Chrome Web Store and has real users.

My role:

The extension, backend, landing page and Chrome Web Store release.

What does the product do?

Three ways to translate

Hover for a quick translation, select text or use the right-click menu.

More than 50 languages

Choose a target language to suit what you are reading.

Adjust the experience

Enable or disable hover translation, block it on selected sites and choose a light or dark interface.

Release and maintenance

The product includes the extension, backend and landing page, with updates after publication.

How do the parts work together?

Users can see translations where they are reading. Preferences can sync through their Chrome account.

Explore the technical details
  • Chrome Manifest V3, content scripts and a backend proxy that keeps API keys on the server.
  • Hover translation uses Google Translate; selected text goes through the AI backend with a fallback provider.
  • Caching and interaction throttling avoid unnecessary translation requests.
Chrome ExtensionNode.jsLLM
Chrome Web Store
PRODUCT JOURNEY
  1. Upload
  2. Publish
  3. Find and watch

Content platform

Streaming & Content Management Platform

Tools for publishers and viewers: upload content, edit subtitles, organize a library, manage access and find the right moment in a video.

  • Publishing
  • Subtitle editing
  • In-video search
  • Access control

My role: The complete website, backend, desktop publishing app and deployment.

Content platform

Streaming & Content Management Platform

The platform connects content management tools with a video and audio library. Publishers prepare and maintain content; viewers browse categories or search for a line in the subtitles and jump to the right moment.

My role:

The complete website, backend, desktop publishing app and deployment.

What does the product do?

Upload and prepare

Upload video or audio and create thumbnails. Use the desktop app to process and publish large files.

Edit subtitles

Edit text and timing, and preview subtitles alongside the video.

Organize the library

Categorize content, change its order and update existing entries.

Find and watch

Search spoken content, jump to a timestamp, watch video or listen to audio.

Share and control access

Share a particular moment and choose public, unlisted or restricted access.

Manage the platform

Manage users, roles and permissions, and review changes in the system.

How do the parts work together?

Publishers can prepare and organize content, while viewers can find the exact segment they need. Access rules apply both to the content page and to search results.

Explore the technical details
  • Subtitle search was redesigned around shorter segments: approximately 54 seconds down to 160 ms on the project's evaluation set, with 92% Recall@1.
  • The system includes a website, backend and desktop app. The desktop app uses native ffmpeg to process files in the documented 300 MB to 2 GB range.
  • Role-based access, three content visibility levels and controls for concurrent updates.
Next.jsHonoPostgreSQLElectron
PRODUCT JOURNEY
  1. Register
  2. Pay
  3. Access materials

Business platform

Course Commerce & CRM Platform

Connect registration, payments, learning materials and learner communications. Staff manage orders, invoices and email campaigns through a CRM.

  • Course registration
  • QR payments
  • Invoicing
  • Learner communications

My role: All backend and business logic, plus the CRM interface. Other teammates contributed the remaining interfaces.

Business platform

Course Commerce & CRM Platform

A platform supporting individual registrations, group purchases and workshop bundles. Learner registration connects with payment confirmation, access to materials and internal administration.

My role:

All backend and business logic, plus the CRM interface. Other teammates contributed the remaining interfaces.

What does the product do?

Flexible registration

Register for a course, buy as a group or choose a workshop bundle with configurable pricing.

Payments and access

Pay by QR code; the system reconciles the payment, confirms the order, creates an account and grants access to materials.

Electronic invoices

Issue invoices after payment and track their status in the CRM.

Communications and management

Send transactional emails, create audience-based campaigns and track where each order originated.

How do the parts work together?

Course sales connect with learner services and internal operations. A confirmed payment remains recorded even if a downstream email or invoicing service fails.

Explore the technical details
  • SePay, MISA meInvoice and email-provider integrations, with duplicate-processing protection and handling for delayed payment notifications.
  • Payment confirmation is separated from downstream tasks, with controls for simultaneous webhook and manual confirmations.
  • I built the backend and business logic; teammates contributed the landing-page and digital-library interfaces.
TypeScriptReactPostgreSQLSePayMISA
Explore 2 more products
PRODUCT JOURNEY
  1. Choose a plan
  2. Register and pay
  3. Manage services

Business platform

Office Services CRM & Customer Portal

Customers register, pay and manage services on the web or Zalo. Operations staff handle applications, contracts and requests in the CRM.

  • Service registration
  • Customer portal
  • CRM
  • Zalo Mini App

My role: All backend, business integrations and the Zalo Mini App. Teammates built the initial web and CRM interfaces.

Business platform

Office Services CRM & Customer Portal

A platform for virtual-office and coworking services, connecting self-service registration with the operations team's work.

My role:

All backend, business integrations and the Zalo Mini App. Teammates built the initial web and CRM interfaces.

What does the product do?

Choose and register

Choose a building, plan, term and add-on services, submit documents and pay by QR code.

Resume an application

Saved drafts let customers return to an unfinished registration.

Customer self-service

Review plans, benefits, payments, contracts, documents and support requests on the web or Zalo.

Internal operations

Manage customers, contracts, orders, invoices, mail, parcels and services through the CRM.

How do the parts work together?

Registration data carries through into service processing and delivery. Customers and staff use interfaces suited to their roles, connected to the same business system.

Explore the technical details
  • One backend serves the customer website, CRM and Zalo Mini App, with authentication suited to each interface.
  • Concurrency controls, permissions and tamper-evident audit logging.
  • I owned the backend and Zalo Mini App, integrated business logic and maintained the web and CRM interfaces initially built by teammates.
HonoPostgreSQLNext.jsZalo Mini App
PRODUCT JOURNEY
  1. Discover
  2. Read updates
  3. Connect

Freelance project

Ho Chi Minh City Traditional Martial Arts Federation Website

An organization's introduction, news and credentials in one place. I handled development and deployment, followed by maintenance and upgrades.

  • Organization profile
  • News
  • Credentials
  • Maintenance

My role: The complete website for the Ho Chi Minh City Traditional Martial Arts Federation.

Visit website

Freelance project

Ho Chi Minh City Traditional Martial Arts Federation Website

The website for the Ho Chi Minh City Traditional Martial Arts Federation includes its introduction, news and credentials. The freelance engagement covers development, deployment, maintenance and upgrades.

My role:

The complete website for the Ho Chi Minh City Traditional Martial Arts Federation.

What does the product do?

Organization profile

Introduction and credentials pages for visitors learning about the organization.

News publishing

Article listings and detail pages, with a documented content-update process.

Discoverability

Metadata, a sitemap and structured data help search engines understand the content.

Ongoing maintenance

Updates and upgrades continued after the website was deployed.

How do the parts work together?

The organization has a central place to introduce itself, publish news and share its credentials. Content-update instructions allow others to continue the work.

Explore the technical details
  • A statically exported Next.js website deployed through GitHub Actions.
  • Initially scaffolded with v0.dev, then developed, upgraded and maintained by me; the project history dates back to March 2025.
Next.jsTypeScriptTailwind CSS
Visit website

HOW I WORK

AI-native development, guided by systems thinking.

I organize a team of AI agents to build products while taking responsibility for the overall design and checking the results. Each task connects to the people using the product, their workflows and the business goals we agree on.

MULTI-AGENT ORCHESTRATION

More than 10 AI agents, working to one plan.

I use an orchestrator to assign tasks and coordinate the agents. Independent work runs in parallel on separate branches; I oversee integration, check quality and decide when the product is ready to release.

  1. I set the directionRequirements, overall design and acceptance criteria.
  2. OrchestratorBreak down work, assign tasks and combine results.
  3. 10+ AI agentsImplement the work assigned to them.
  4. I validateReview, integration checks and release decisions.
Context Engineering: experience the next project can use

I document why a solution was chosen, what went wrong and how it was resolved, then package that knowledge into documentation and skills agents can consult. My VPS deployment, server hardening and e-invoicing guides all come from practical work.

SYSTEMS THINKING

See the whole picture. Understand the impact of each decision.

I consider how people, processes, data and technology influence one another. When solving a problem, I look for causes in how the whole system operates, weigh the consequences of each change and use real-world feedback to adjust. Every decision should support the shared goals of the product and the business.

ILLUSTRATIVE EXAMPLE

Bringing AI into a business: make the whole workflow more effective.

An AI assistant can answer quickly and still create more work for staff if its answers are inaccurate and frequently need correcting. Data quality, the scope of AI's work and collaboration with people all need to be considered together.

This loop can arise when the same team both corrects mistakes and updates the documentation:
  1. Outdated data
  2. Incorrect AI answers
  3. Staff busy correcting errors
  4. Less time to update data

Less time for updates leaves the data outdated, returning to the start of the loop.

Where to intervene

I identify what needs to change across the workflow: who keeps data up to date, what AI is allowed to handle and which situations should be passed to a person.

Measure the effect through

  • Quality of completed work
  • Amount of rework
  • Time the team actually saves

Clarify and agree

Identify the users, workflows and first priorities together. Agree on scope and acceptance criteria before development starts.

Build in reviewable stages

Divide the work into parts we can check, discuss the results and address decisions that affect the whole product.

Validate and hand over

Check the agreed requirements and user journeys, prepare the release and agree on handover documentation and ongoing maintenance.

ABOUT ME

From the first requirements to a product in use.

Full-stack Developer | AI-native development

Explore my experience in my CV

I'm Hai, a developer based in Ho Chi Minh City. I have owned the backend of two business platforms, built management interfaces and worked with teammates responsible for other parts of the products.

On personal and freelance projects, I handle development, deployment and ongoing maintenance. Working in both settings has helped me understand how my decisions affect users, teammates and the product as a whole.

Explore my technical background

My strengths are backend development, system integration and operations. I also build AI agents, organize agentic engineering workflows and turn practical experience into reusable documentation and agent skills.

TypeScriptJavaScriptC#ReactNext.jsNode.jsHonoExpress.NETPostgreSQLDrizzle ORMDockerCaddyVercel AI SDKMCP

LET'S TALK ABOUT YOUR PROJECT

Let's build your next product.

Need a website, a management system or a way to bring AI into your workflow? Tell me what you have in mind and we can discuss how to build it.

[email protected]
Ho Chi Minh City, Vietnam
GitHub ↗LinkedIn ↗Facebook ↗Zalo ↗

Start with the problem you want to solve.

You don't need a complete specification yet. A few details will help:

  • Who the product is for and what it should help them do.
  • The features you need or the system you want to improve.
  • Your preferred timeline and budget, if you have them.
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