I turn messy, disconnected data into reliable dashboards and decision-ready insights that leaders actually use. I'm a Data & Analytics Engineer who bridges production-grade data engineering and C-suite business intelligence. I build automated pipelines, clean data models, and high-impact BI solutions across Power BI, Tableau, and Looker Studio. What I deliver for you: • BI & Dashboards, Interactive Power BI and Tableau dashboards with star-schema models, DAX, and Power Query that track KPIs, surface trends, and justify strategic decisions. • Analytics Engineering, Modern dbt workflows delivering version-controlled, tested, production-grade SQL transformations (Git/Bitbucket). • Pipeline Automation, Resilient, dependency-aware Apache Airflow DAGs that replace manual ETL, cutting processing time and failures. • Data Modeling, Optimized star schemas and dimensional structures across Postgres, MySQL, Synapse, and enterprise databases for fast queries. • Insight Generation, Deep root-cause analysis, exploratory data analysis, and reporting automation that flag anomalies and extract actionable KPIs. I've delivered enterprise analytics for finance, insurance, fintech, retail, and e-commerce clients, including AML/KYC reporting workloads. Keywords to connect with me: Power BI, Tableau, Looker Studio, SQL, DAX, Power Query, data analytics, business intelligence, dashboard development, KPI dashboard, data visualization, ETL, dbt, Airflow, data modeling, reporting automation, Excel, data cleaning

Building the foundation for intelligent business decisions through well-constructed, reliable data. Hi! I am a Data Engineer specialized in designing, building, and optimizing scalable, secure, and highly reliable data infrastructures. I focus on the entire data lifecycle—from ingestion and processing to storage and consumption—ensuring your data is ready to generate real business value. If your data pipelines are slow, hitting memory limits, or causing high cloud compute costs, I can help you build a robust solution that guarantees optimal performance and absolute data quality. --- MY CORE ENGINEERING APPROACH --- INGESTION & SCALABLE ARCHITECTURE I extract data from diverse sources including APIs, flat files, legacy databases, and continuous logs. By designing custom-fit, scalable architectures, I ensure that the foundation of your data grows seamlessly alongside your business operations. I build solutions that guarantee high availability and fault tolerance from the very first point of data entry, eliminating silos. BIG DATA PROCESSING & OPTIMAL PERFORMANCE I build distributed, lightning-fast ETL/ELT pipelines utilizing Apache Spark, Databricks, and Apache Kafka. For highly optimized batch processing and memory-efficient workflows, I leverage modern frameworks like Python, Polars, and DuckDB. I have extensive hands-on experience orchestrating massive migrations and deduplicating complex datasets (consistently processing and merging 12.3M+ records). I excel at diagnosing and resolving deep performance bottlenecks, such as fixing Out-of-Memory (OOM) errors and enforcing strict schema validation—like executing rigorous string parsing and casting—to ensure seamless, optimized Parquet exports without any data loss. SPATIAL DATA & GIS ENGINEERING Beyond standard tabular data, I possess specialized expertise in Geographic Information Systems (GIS) and spatial data engineering. I am highly proficient in industry-standard tools like QGIS, Smallworld, and ArcGIS. I regularly process, transform, and georeference heavy spatial datasets, integrating complex location-based network infrastructure (such as fiber optic deployments and telecommunications networks) directly into core cloud data warehouses. This allows businesses to perform advanced spatial analysis and visualize geographic assets effectively. SECURE & SCALABLE STORAGE I structure modern Data Lakes and Cloud Data Warehouses using industry-leading technologies like Snowflake, AWS, Azure, and Google Cloud. I implement highly efficient columnar storage formats (like Parquet and Arrow) to drastically reduce cloud storage costs while maximizing analytical query performance for end-users. DATA GOVERNANCE & SECURITY A pipeline is only as good as the trust you place in its data. I implement rigorous data quality checks, continuous monitoring, and strict security protocols throughout the entire data lifecycle. I ensure that all data is precise, secure, auditable, and fully compliant with internal governance standards. --- BUSINESS VALUE I DELIVER --- FASTER DECISIONS: By ensuring your data is structured, clean, and ready exactly when you need it, I empower your team to act on real-time insights without waiting for slow queries. COST REDUCTION: Through the optimization of cloud resources, efficient processing frameworks, and the elimination of manual pipeline re-work, I significantly cut down your operational data costs. COMPETITIVE ADVANTAGE: I turn chaotic, fragmented, and raw data into a reliable, unified asset that drives business growth and builds absolute trust in your company metrics. --- MY TECHNOLOGY STACK --- Big Data & Distributed Computing: PySpark, Databricks, Apache Spark, Apache Kafka. Data Processing & Languages: Python (Polars, Pandas), Advanced SQL, dbt. Cloud Infrastructure & Warehousing: AWS, Google Cloud Platform (GCP), Microsoft Azure, Snowflake. Storage & Databases: DuckDB, PostgreSQL, Parquet, Delta Lake. GIS & Spatial Analysis: QGIS, Smallworld, ArcGIS. --- MY METHODOLOGY --- DISCOVER: Deeply understanding your raw data landscape and core business objectives. DESIGN: Architecting custom-tailored data pipelines, scalable models, and infrastructure. BUILD: Implementing robust, scalable engineering solutions with clean, documented code. OPTIMIZE: Continuously improving query performance, cost-efficiency, and overall data quality. MONITOR: Ensuring high availability, continuous validation, and the steady improvement of your data architecture. Your Data. My Engineering. Your Future. I partner with businesses not just to write code, but to become a long-term strategic data ally. Click "Invite to Job" and let's build the infrastructure that drives your business forward today!

I’m a Data Engineer with ~3 years of professional experience, specialized in cloud-based data platforms, data architecture, and scalable ETL pipelines. I help companies design, build, and improve reliable data pipelines that support analytics, reporting, and data-driven decision making. What I do best: * Design and implement end-to-end data pipelines (from APIs and databases to data warehouses) * Build and maintain cloud-native data platforms on AWS * Model data for analytics using SQL and dbt * Integrate multiple external data sources (APIs, SaaS tools, operational databases) * Improve performance, reliability, and cost efficiency of existing pipelines My experience includes: * Designing data pipelines from scratch and maintaining high-volume production systems * Working closely with analysts, product, and business stakeholders * Applying data architecture best practices to build scalable and maintainable platforms Tech stack: * Python, SQL * AWS * dbt, PostgreSQL * Serverless architectures, Infrastructure as Code * Experience with GCP If you’re looking for a reliable freelance Data Engineer to help you build or improve your data platform, I’d be happy to discuss your project.

I'm a data engineer with 8+ years building production data infrastructure. I specialize in three areas: 1. ETL/ELT Pipeline Development: I design and build pipelines that reliably move data from source systems into your warehouse. I've engineered workflows handling millions of records daily, implemented incremental loads for performance, and built error handling to ensure reliability. Whether you're integrating APIs, migrating systems, or automating workflows, I deliver scalable pipelines. Data Warehouse Design: I architect data warehouses that serve analytics and operational needs. I design relational models across staging and analytics layers, optimize query performance, and reduce costs. My approach: understand your business questions, design the schema that answers them efficiently, then optimize iteratively. Analytics Engineering: I build transformation layers and create dashboards in Looker, Tableau, or Power BI. I've consolidated multiple data sources into unified datasets, reducing reporting prep from 30+ hours to seconds. I design dimensional models, define metrics, and ensure data quality. Technical: Python, SQL, dbt, Snowflake, AWS, Looker, Power BI, Tableau, REST APIs, data modeling, workflow automation. I work best with startups scaling infrastructure, mid-market companies with pipeline issues, or teams migrating data platforms. I move fast, communicate clearly, and deliver reliable solutions.

🚀 Senior Data Engineer | Snowflake | SQL |Databricks | Azure Data Factory | DBT | Snowpark |Snowflake Cortex | Python | Pyspark | Data Modeling(Star and Snowflake Schema) | Data Vault 2.O | Azure | AWS I am a Senior Data Engineer with 8+ years of experience designing, developing, and optimizing cloud-based data platforms and analytics solutions. I specialize in Snowflake, Databricks, Azure Data Factory (ADF), DBT, PySpark, Python, SQL, and modern data warehousing architectures. I have successfully delivered end-to-end data engineering solutions across Healthcare, Banking, Insurance, Manufacturing, and Financial Services domains, helping organizations build scalable, reliable, and high-performance data platforms. My expertise includes: ✔ Snowflake Data Warehouse Development & Optimization ✔ Databricks & PySpark Data Engineering ✔ Azure Data Factory (ADF) Pipeline Development ✔ DBT Data Transformation & Modeling ✔ ETL / ELT Pipeline Design & Automation ✔ API Integration & Data Ingestion Frameworks ✔ Data Modeling (Star Schema, Snowflake Schema, Data Vault 2.0) ✔ Snowpipe, Streams & Tasks Implementation ✔ Airflow Workflow Orchestration ✔ Performance Tuning & Cost Optimization ✔ Data Quality Validation & Reconciliation Frameworks ✔ Power BI & Tableau Data Preparation I have experience building enterprise-scale data pipelines, cloud migrations, data warehouse modernization initiatives, regulatory reporting solutions, and analytics platforms using industry best practices. My goal is to deliver scalable, secure, and business-focused data solutions that provide accurate insights and measurable value to organizations. If you need a Snowflake Data Engineer , Databricks, or Azure Data Engineering expert who can independently drive a project from requirements gathering to production deployment, I'd be happy to help.

Data professional with6+ years of experience delivering data engineering, analytics, and business analysis solutions across the airline, banking, and IT industries. SnowPro Core Certified Data Engineer, experienced in designing and maintaining ELT/ETL pipelines using Snowflake, dbt, Python, SQL, Airflow, Databricks, and AWS. Skilled in data modeling, data warehousing, performance optimization, data quality, reporting, and automation. Core Skills: Snowflake, dbt, SQL, Python, Airflow, Databricks, AWS, Terraform, Git, AWS, GCP, CI/CD, ETL/ELT Pipelines, Data Warehousing, Data Modeling, Business Analysis, Requirement Gathering, BRD, FRD, User Stories, Use Cases, Manual Testing, UAT, Documentation, Power BI, Problem Solving, and Stakeholder Management.

I've spent 15+ years as a Senior Data Platform Engineer building and maintaining production reporting systems for multi-tenant SaaS and industrial environments. I help data-intensive SaaS companies modernize and stabilize large database systems by optimizing slow SQL, execution plans, indexing strategies, ETL workflows, and warehouse performance across PostgreSQL, MySQL, Snowflake, and SQL Server. My strongest work is in performance-heavy environments where reporting, analytics, pricing logic, monitoring, and automated decision-making depend on clean, fast, reliable data. I have optimized long-running production queries, redesigned indexing and archival strategies, improved ETL/data synchronization flows, and supported modernization of large operational databases without disrupting live products. 𝗪𝗵𝗮𝘁 𝗰𝗹𝗶𝗲𝗻𝘁𝘀 𝘀𝗮𝘆: "Optimized our data models and indexing strategy, cutting report generation time while rolling out to new clients with zero issues." "Built and owned the automated publishing pipeline that now reliably serves our full client reporting fleet." "Clear ownership and proactive monitoring during our platform modernization - exactly the engineer we needed." 𝗦𝗤𝗟 𝗦𝗲𝗿𝘃𝗲𝗿 𝗘𝗻𝗴𝗶𝗻𝗲𝗲𝗿𝗶𝗻𝗴 & 𝗠𝗶𝗴𝗿𝗮𝘁𝗶𝗼𝗻 ✔ Design and optimize complex queries, views, stored procedures, and data models for large-scale production reporting ✔ Execution plan analysis, indexing strategy, and performance tuning across multi-tenant environments ✔ Lead SQL Server version migrations and schema modernization with full compatibility and regression testing ✔ Maintain and extend optimized view/indexing architectures mid-rollout while preserving stability 𝗔𝘂𝘁𝗼𝗺𝗮𝘁𝗲𝗱 𝗣𝗶𝗽𝗲𝗹𝗶𝗻𝗲𝘀 & 𝗧𝗮𝗯𝗹𝗲𝗮𝘂 𝗣𝗹𝗮𝘁𝗳𝗼𝗿𝗺 𝗢𝗽𝗲𝗿𝗮𝘁𝗶𝗼𝗻𝘀 ✔ Operate and extend GitHub-based workbook duplication/publishing pipelines using Python, REST APIs, and GitHub Actions ✔ Manage extract scheduling against production OLTP databases and minimize refresh load ✔ Maintain and deploy Tableau workbooks across dev/UAT/production supporting ~100 per-client reports ✔ Tableau Server administration, extract monitoring, and proactive root-cause resolution for failures or degradation ✔ Support smooth transition of reporting workloads to in-app platforms while keeping Tableau reliable 𝗠𝗼𝗻𝗶𝘁𝗼𝗿𝗶𝗻𝗴, 𝗥𝗲𝗹𝗶𝗮𝗯𝗶𝗹𝗶𝘁𝘆 & 𝗖𝗿𝗼𝘀𝘀-𝗙𝘂𝗻𝗰𝘁𝗶𝗼𝗻𝗮𝗹 𝗣𝗮𝗿𝘁𝗻𝗲𝗿𝘀𝗵𝗶𝗽 ✔ Implement proactive monitoring (New Relic / equivalent) to detect and resolve issues before client impact ✔ Strong troubleshooting with clear communication to technical and business stakeholders on performance and risk ✔ Collaborate with Data Engineering, Infrastructure, and domain experts during platform migrations and architectural decisions 𝗪𝗵𝘆 𝗖𝗹𝗶𝗲𝗻𝘁𝘀 𝗛𝗶𝗿𝗲 𝗠𝗲 ✔ Full end-to-end ownership of production reporting stacks - SQL optimization, automation pipelines, and operational reliability ✔ Proven experience with multi-tenant client reporting environments and regulated industrial data (directly applicable to healthcare compliance) ✔ Deep expertise in database migrations, Python/GitHub automation, and performance tuning - exactly the skills for your SQL Server modernization ✔ Licensed P.Eng with 15+ years delivering stable, high-trust production systems with clear ownership and honest timelines I work best with teams modernizing SQL Server environments or scaling Tableau operations who need a hands-on engineer to complete remediation work, stabilize the platform, and keep reporting fast and trusted. Send me a message with your current migration status and pipeline pain points - I’ll outline exactly how I’d approach finishing the work with zero client impact. 𝗞𝗲𝘆𝘄𝗼𝗿𝗱𝘀: PostgreSQL, MySQL, Snowflake, Yellowbrick-compatible warehouse tuning, execution plan analysis, query rewrites, indexing, memory tuning, ETL optimization, large data footprints, SaaS modernization, pricing analytics, eCommerce intelligence, brand monitoring data.

Turn messy, complex data into reliable, scalable, and production-ready systems. I am a Data Engineer and Architect with over 5 years of experience specializing in the entire data lifecycle. From building real-time streaming architectures to deploying cost-efficient cloud analytics platforms, I bridge the gap between raw data and actionable business value. With a background in both Data Engineering and Data Science, I don't just move data; I ensure it is modeled for high-performance analytics and predictive insights. Core Expertise & Services: • Data Warehouse & Lakehouse Architecture: Custom-designed, scalable solutions using Databricks (Delta Lake), and BigQuery. • ETL/ELT Pipeline Development: Robust data workflows using Python, SQL, dbt, and Apache Spark. Real-Time Streaming: High-performance systems utilizing Kafka, Flink, and Spark Streaming (Scala/Python). • Orchestration & MLOps: End-to-end workflow automation with Apache Airflow; production-grade MLOps pipelines using MLflow for experiment tracking and model lifecycle management; CI/CD pipelines with Jenkins, GitHub Actions, Terraform, and Helm. Real-time change data capture (CDC) architectures with Debezium integrated into Kafka-based systems. • Infrastructure & DevOps: Production-ready containerization via Docker & Kubernetes across AWS, GCP, and Azure, or specialized on-premises environments. • Database Migrations: Seamless metadata upgrading and migration for PostgreSQL, MySQL, and NoSQL systems. • AI Engineering & LLMOps: Building production-ready LLM-based systems, RAG architectures, and vector data modeling integrated with MLflow for scalable AI deployment. • AI-Driven Automation & Orchestration: Designing and deploying autonomous AI agents and advanced workflow automation using n8n. Expert in bridging LLMs, vector databases, and enterprise data pipelines into production-ready, self-hosted or cloud-based autonomous systems that orchestrate complex business logic. Technical Stack: Languages: Python (FastAPI), Scala, SQL. Big Data Tools: Spark, Trino, Flink, Hadoop, Hive. Data Ops, MLOps & Automation: Airflow, dbt, n8n (AI Agent Workflows), Kafka, Debezium (CDC), MLflow, Jenkins, CI/CD pipelines. Cloud: AWS, GCP, Azure, MinIO. Monitoring & Logging: Elasticsearch, Kibana Visualization: PowerBI, Tableau, Looker Studio Proven Impact: Award-Winning Solutions: Led a freight price estimation project that achieved 78% accuracy, winning the Ministry of Trade Digital Transformation Award. Cost Efficiency: Reduced annual operational costs by $150K through optimized data architecture and predictive modeling. Global Collaboration: Extensive experience working with international teams across Europe and Turkiye, combining technical leadership with business strategy. Whether you need a complete migration to the cloud or a real-time analytics dashboard, I am here to build the engine that powers your growth. Let's discuss how I can optimize your data infrastructure and unlock valuable insights for your business. Click "Invite to Job" or "Message" to start the conversation!

I’m Mai Văn Duyên, a Data Engineer with 4+ years of experience building scalable data pipelines, analytics platforms, and AI-powered solutions. I specialize in Python, SQL, Dagster, dbt, Snowflake, Fabric, and Power BI, with hands-on expertise in LLM workflows using LangChain and FastAPI. I’ve delivered pipeline optimizations, cost-saving tool replacements, and end-to-end ETL/ELT systems for enterprise clients. Let’s work together to turn your data into reliable insights and automation.

𝐃𝐚𝐭𝐚 𝐄𝐧𝐠𝐢𝐧𝐞𝐞𝐫 & 𝐁𝐈 𝐀𝐧𝐚𝐥𝐲𝐬𝐭 𝐟𝐨𝐫 𝐒𝐐𝐋, 𝐏𝐲𝐭𝐡𝐨𝐧, 𝐏𝐨𝐰𝐞𝐫 𝐁𝐈, 𝐓𝐚𝐛𝐥𝐞𝐚𝐮, 𝐄𝐓𝐋, 𝐚𝐧𝐝 𝐃𝐞𝐜𝐢𝐬𝐢𝐨𝐧-𝐑𝐞𝐚𝐝𝐲 𝐃𝐚𝐬𝐡𝐛𝐨𝐚𝐫𝐝𝐬 If your business has scattered data, slow reports, or dashboards that do not match the numbers your team trusts, I can help turn that into a clean, reliable analytics workflow. My focus is building data pipelines, BI dashboards, and reporting systems that make decisions faster and easier. 𝑨𝑩𝑶𝑼𝑻 𝑴𝑬 I specialize in data engineering, data visualization, and business analysis for teams that need accurate reporting without unnecessary complexity. I work across SQL databases, Python workflows, Power BI, Tableau, Looker Studio, BigQuery, Snowflake, and spreadsheet-heavy environments that need better structure. My background includes building reporting layers for SaaS, ecommerce, operations, finance, and customer support teams. I care about clean metric definitions, repeatable pipelines, dashboard usability, and data that business users can actually trust. 𝑾𝑯𝑨𝑻 𝑰 𝑶𝑭𝑭𝑬𝑹 ✅ Power BI and Tableau dashboards with clear KPIs, filters, drilldowns, and stakeholder-ready visuals ✅ SQL reporting models for revenue, customer behavior, operations, finance, and product analytics ✅ ETL pipeline development using Python, SQL, Airflow, dbt, BigQuery, Snowflake, and API data sources ✅ Data cleaning and transformation for messy spreadsheets, CRM exports, ecommerce data, and operational systems ✅ Dashboard optimization and QA to fix slow refreshes, broken metrics, duplicate records, and inconsistent totals ✅ Analytics documentation including KPI definitions, data dictionaries, refresh logic, and handover notes 𝑻𝑬𝑺𝑻𝑰𝑴𝑶𝑵𝑰𝑨𝑳𝑺 👍 "The dashboard was clean, practical, and easy for our managers to use." 👍 "He helped us replace manual spreadsheet reporting with a much smoother workflow." 👍 "Strong SQL work and clear communication during every review." 👍 "The final reports matched our business logic and were delivered with useful documentation." 𝑲𝑬𝒀 𝑺𝑻𝑹𝑬𝑵𝑮𝑯𝑺 💠 SQL-first analytics thinking with strong attention to metric accuracy 💠 Business-friendly dashboards that avoid clutter and focus on decisions 💠 ETL and data modeling for repeatable reporting instead of one-off fixes 💠 Data validation and QA before dashboards go live 💠 Clear documentation for handover, maintenance, and future scaling 💠 Stakeholder communication with both technical and non-technical teams 💠 Practical problem-solving for real business data issues 𝑺𝑲𝑰𝑳𝑳 𝑺𝑬𝑻 🧰 BI & Visualization: Power BI, Tableau, Looker Studio, dashboard design, KPI reporting, executive reports 🧰 Data Engineering: ETL pipelines, data warehousing, dbt, Apache Airflow, API data ingestion, batch processing 🧰 Databases & Querying: SQL, PostgreSQL, MySQL, BigQuery, Snowflake, SQL Server 🧰 Analytics & Automation: Python, pandas, Excel, Google Sheets, data cleaning, reporting automation 🧰 Data Quality: validation rules, duplicate checks, reconciliation, documentation, refresh monitoring If you need a data engineer, data analyst, or BI dashboard specialist who can clean up the reporting process and deliver useful insights, send me a message and I will help map the best approach. Keywords: data engineer, data analyst, data visualization, Power BI, Tableau, SQL, Python, ETL pipeline, data warehouse, BigQuery, Snowflake, Looker Studio, dbt, Apache Airflow, business intelligence, dashboard design, KPI reporting, data cleaning, data modeling, reporting automation, Excel reporting, analytics dashboard, BI developer, data transformation, data quality