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Top Rated · 100% Job Success · You keep full ownership of everything I build. I am a full stack developer, database architect, and SaaS developer. I design scalable database systems, build production-ready web applications, and integrate AI into products that work for real users. Full stack developer. Next.js. TypeScript. End to end. As a full stack developer I own the entire stack PostgreSQL schema design, Node.js backend, Next.js and React frontend, REST API integrations, Stripe payments, and Vercel deployment. Need a full stack developer who takes ownership from database to deployment without hand-holding? Let's talk. Recent full stack work includes a multi-tenant property management SaaS on Next.js and Supabase with role-based access, admin dashboards, and OpenAI integrations and a freelance marketplace with a GraphQL API layer, BullMQ background job queues, and row-level security enforcing per-user data isolation across clients and freelancers. Database architect. PostgreSQL. Supabase. SQL. Production-grade. As a database architect I design schemas from scratch normalization, ERD modelling, indexing strategies, query optimization, and Row Level Security policies. I migrate businesses from messy Excel and Google Sheets into clean, scalable PostgreSQL and Supabase systems with zero data loss and full audit trails. Recent database work includes a fuel business management platform with complex relational schema covering customers, orders, deliveries, invoicing, and payment cycles and a POS system with real-time inventory tracking, sales reporting, and automated invoice generation, all built on Supabase and PostgreSQL. Backend developer. Node.js. NestJS. REST APIs. As a backend developer I build structured, scalable Node.js and NestJS APIs with TypeScript end to end modular architecture, dependency injection, guard-based authentication, and clean REST API layers. I design and implement authentication flows, role-based access control, webhook handling, and background job processing for production applications that need to scale reliably. SaaS developer. Multi-tenant. Stripe. Production-ready. As a SaaS developer I build complete products end to end authentication, database, Stripe subscriptions and webhooks, dashboards, role-based access, and deployment. I have delivered a business management platform with automated PDF invoicing, cron-based billing cycles, and email dispatch via Resend; a wedding management system with client records, fare packages, and booking history; and a lead management dashboard with WhatsApp automation via ManyChat and automated drip campaigns. AI developer. OpenAI. Claude API. LLM integrations. As an AI developer I integrate LLM APIs into production applications document processing pipelines, AI-powered workflow automation, structured prompt engineering, and AI-assisted data extraction. All API keys handled server-side, never exposed to the browser. I have built OpenAI and Claude integrations into SaaS platforms delivering real features, not demos. Security. Supabase RLS. Multi-tenant isolation. I implement Row Level Security on every Supabase project enforcing per-user and per-tenant data isolation at the database level, not just the application layer. RLS policies, protected API routes, secure file access via signed URLs, and environment variable hygiene are standard practice on every project I deliver. Integrations. Automation. Third-party APIs. QuickBooks API integration for financial data sync into web dashboards. Airtable integrations. ManyChat and WhatsApp API automation. Resend for transactional email. Stripe checkout, subscriptions, webhooks, and billing portals. REST API development and third-party service connections across every project. How I work: Daily updates, no ghosting. Honest timelines. 30+ hours per week. 0–4 hour response time. I use Cursor and Claude Code daily to move fast without cutting quality. Full code ownership transferred on every handover. Stack: PostgreSQL · Supabase · SQL · pgvector · MongoDB · Prisma · Redis · Next.js · React · Nest.js · TypeScript · JavaScript · Tailwind CSS · Shadcn UI · Stripe · OpenAI · Claude API · Node.js · Express · Docker · Vercel · Railway · AWS · Cloudflare R2 · QuickBooks API · Airtable · ManyChat · WhatsApp API · Resend · GraphQL · BullMQ · REST APIs Message me with what you need database design, SaaS build, AI integration, or all three. I'll give you a straight answer on whether I can help and how long it takes.

⏰ Available 24/7 – Long-term & High-impact Projects Hi, I’m Nghi, a Senior Data Engineer and Data Architect with a strong backend foundation, now focused on building high-performance analytics platforms, explainable data pipelines, and production-grade cloud architectures. I help companies transform unreliable, slow, or opaque data systems into scalable, well-documented, and business-trustworthy platforms. 🧠 WHAT I SPECIALIZE IN 🏗️ Data Architecture & Platform Design - Designing modern lakehouse & warehouse architectures - dbt-first analytics engineering with testing, freshness & lineage - Event-driven and batch hybrid pipelines - Data quality frameworks & SLA monitoring - Customer-facing data explainability systems Tools: dbt, Dagster, Airflow, Spark, Kafka, Snowflake, BigQuery, Redshift, PostgreSQL, DuckDB, ClickHouse ⚡ Database Performance Engineering - If your queries are slow, costs are high, or dashboards lag, This is my zone - Query plan analysis & index strategies - Warehouse cost optimization (Snowflake, BigQuery, Redshift) - OLTP & OLAP performance tuning - High-concurrency workload design 🔄 Reverse ETL & Operational Analytics - Syncing analytics back to CRMs & internal tools - Building real-time metrics pipelines - Feature-store style transformations 🕷️ Enterprise-grade Web Data Extraction - I don’t just scrape pages, I build durable data acquisition systems: - Complex ASP.NET, JS-heavy, authenticated & paginated systems - Anti-bot bypassing & failure-recovery pipelines - Headless browser automation + async scraping - Real-estate, finance, campaign-finance & marketplace platforms ☁️ Cloud Infrastructure - AWS | Azure | GCP - EMR / Dataproc / Glue / Dataflow / Synapse / BigQuery / Redshift - Terraform-based deployments - Cost-aware architectures - Kubernetes + Dockerized data services 🧪 What You Get Working With Me ✔️ Production-ready pipelines ✔️ Clean, testable dbt models ✔️ Well-documented architecture diagrams ✔️ Transparent data logic for non-technical stakeholders ✔️ Systems that scale beyond MVP ✔️ Honest advice and not over-engineering 🏆 Ideal Projects 👍 Data warehouse migrations 👍 Broken pipelines that need debugging & stabilization 👍 Analytics platforms that lack trust or explainability 👍 Performance bottlenecks costing thousands per month 👍 Long-term data platform ownership ❣️ Why Clients Stay Long-Term 🍀Clear communication 🍀 Business-first thinking 🍀 No black-box systems 🍀 I build systems others can maintain 🇻🇳🇻🇳🇻🇳🇻🇳 If your data platform feels fragile, slow, or impossible to explain to customers, I can fix that. Let’s make your data system something you can confidently stand behind.

Senior Node.js & PHP Developer | Backend, APIs & Microservices | 10+ Years Experience I’m a senior web developer with 10+ years of professional experience building scalable, secure, and high-performance web applications, APIs, and backend systems. I specialize in Node.js, PHP, JavaScript, REST APIs, microservices, databases, and cloud infrastructure, helping startups and established businesses turn ideas and requirements into reliable, production-ready solutions. ### What I can help you with: 🚀 Node.js & Backend Development – Express.js, REST APIs, real-time applications, microservices architecture, scalable backend systems, and server-side development. 🔗 Microservices Development – Designing and developing scalable, modular microservices, service-to-service communication, API integration, authentication, and backend architecture. 💻 PHP Development – Laravel, CodeIgniter, custom web applications, CMS, and server-side development. 🌐 Full-Stack Development – JavaScript, React.js, Vue.js, HTML/CSS, and modern web applications. 🗄️ Database Development – MySQL, PostgreSQL, MongoDB, and Redis, including database design, optimization, and performance tuning. 💳 API & Payment Integration – Third-party APIs, payment gateways, authentication, and custom integrations. ☁️ Cloud & Deployment – AWS (EC2, Lightsail, S3), DigitalOcean, cPanel, Plesk, Git, and production deployments. ### Why work with me? ### * 10+ years of real-world development experience * Strong expertise in backend development, APIs & microservices * Clean, maintainable, and scalable code * Experienced with new development and existing/legacy codebases * Strong debugging and complex problem-solving skills * Clear communication and a results-oriented approach * Focus on building reliable, production-ready solutions Whether you need a new application built from scratch, microservices developed, APIs created, an existing system optimized, a difficult bug fixed, or a backend scaled, I can help. Let's discuss your project and find the right technical solution for it.

Your team is losing hours every week exporting data by hand. Your dashboards time out because nobody ever tuned the queries behind them. Reports arrive too late to act on, and half the numbers don't match between departments. That's the problem I get hired to solve. I'm a Business Economist and Data Analyst with 4+ years turning messy, manual, or slow data operations into automated systems that just work. 🔧 What I actually do: I automate what's eating your team's time. For a US-based education holding company running 8 separate entities, the VP of Finance was spending 2 full days a week manually exporting QuickBooks data and pasting it into shared sheets. I built a Python pipeline on GCP that runs the whole thing daily, automatically, with fault isolation per entity. Result: 16 hours a week back, zero manual touchpoints, 100% accuracy. I turn scattered data into a business health dashboard your leadership actually trusts. Right now I'm running this exact playbook for an import/export distribution company: connected their Odoo ERP straight to BigQuery, designed a proper data mart (Kimball star schema), and I'm building out the KPI dashboards leadership uses to see the business in real time. Along the way, I don't just build what's asked, I actively flag data quality issues nobody had caught (unconverted foreign currency getting mixed into totals, negative delivered quantities) before they turn into bad decisions. I fix slow queries, not just build reports on top of them. Dashboards are only as fast as the SQL behind them. I do hands-on query tuning: EXPLAIN ANALYZE, indexing strategy, cost-based optimization. In one project I took a query from ~600ms down to under 10ms. If your reports are slow, timing out, or your database groans under load, that's a fixable problem, not something to just live with. 💰 Also worth knowing: earlier in my career I translated financial data into upsell/cross-sell strategy that generated $1.5M+ in net profit, so I don't just automate processes, I know which numbers actually move the business. 🛠 Tech Stack & Tools: • BI & Visualization: Power BI (DAX), Looker Studio (formerly Data Studio), Tableau • Databases: PostgreSQL, MySQL, BigQuery, MongoDB, Databricks • Integrations & APIs: QuickBooks Online REST API, Odoo API, OAuth 2.0 • Automation & Programming: Python (Pandas, NumPy), GCP (Cloud Functions, Scheduler), Power Query, KNIME • Query Performance & Tuning: EXPLAIN ANALYZE, B-Tree Indexing, Execution Plan Analysis, Query Refactoring, Cost-Based Optimization I am actively seeking opportunities where I can apply my unique blend of analytical skills and commercial perspective to help forward-thinking international companies make smarter, data-driven decisions. If your data operation runs on manual work, slow queries, or reports nobody fully trusts, let's talk. 📩 Send me an invite or drop a message with what's slowing your team down