I'm Huanqing Zhu, and you can call me Fusion. With over 10 years of hands-on Java development experience—including 6 years dedicated to big data processing and visualization—I’ve built my expertise by staying rooted in frontline coding, even as my responsibilities have grown. A key pillar of my technical toolkit is ‌6 years of production-grade Rust development experience‌, complemented by proficiency in Java, Scala, JavaScript, HTML5, and a full stack of big data and cloud-native technologies: Apache Spark, Hadoop, Hive, Flume, HBase, Storm, Kafka, DataX, ECharts, Docker, Kubernetes, and Linux. What sets me apart is that I’ve never stepped away from writing production code, even as I’ve taken on leadership and architectural roles: As a ‌hands-on Big Data Developer‌, I’ve built robust data ingestion utilities (including the open-source DataXServer on GitHub) and real-time page click analytics systems, directly coding pipelines to pull data from RDBMS, NoSQL databases, and file storage into production environments. As a ‌Big Data Architect‌, I’ve led platform design while still contributing core code, using Hadoop, Spark, Flink, and ElasticSearch to build scalable data infrastructure—no abstract planning here; I’ve written the critical components that power these systems. As a ‌Rust Specialist‌, my 6 years of experience spans building high-performance, low-latency systems. I’ve used Rust to optimize data processing pipelines, cut latency by up to 40% in high-throughput scenarios, and deliver systems that run 24/7 with zero critical errors. As a ‌Team Leader‌, I’ve managed full-stack teams (Java, front-end, QA, operations) while still pairing with developers on complex code reviews and contributing to high-priority features, ensuring I stay connected to the day-to-day challenges of software delivery. I also bring deep experience in microservices architecture and cloud-native containerization, and my cross-language expertise lets me bridge gaps between Java-based enterprise systems and Rust-powered high-performance components. If you’re looking for a professional who combines strategic vision with the grit to deliver production-ready code—someone who can architect a system, and write the Rust or Java code that makes it run—I’m the candidate for you. Thank you for reviewing my profile. I’m eager to discuss how my hands-on experience can add value to your team.

Seasoned data engineer with over 11 years of experience in building sophisticated and reliable ETL applications using Big Data and cloud stacks (Azure and AWS). TOP RATED PLUS . Collaborated with over 20 clients, accumulating more than 2000 hours on Upwork. 🏆 Expert in creating robust, scalable and cost-effective solutions using Big Data technologies for past 9 years. 🏆 The main areas of expertise are: 📍 Big data - Apache Spark, Spark Streaming, Hadoop, Kafka, Kafka Streams, Trino, HDFS, Hive, Solr, Airflow, Sqoop, NiFi, Flink 📍 AWS Cloud Services - AWS S3, AWS EC2, AWS Glue, AWS RedShift, AWS SQS, AWS RDS, AWS EMR 📍 Azure Cloud Services - Azure Data Factory, Azure Databricks, Azure HDInsights, Azure SQL 📍 Google Cloud Services - GCP DataProc 📍 Search Engine - Apache Solr 📍 NoSQL - HBase, Cassandra, MongoDB 📍 Platform - Data Warehousing, Data lake 📍 Visualization - Power BI 📍 Distributions - Cloudera 📍 DevOps - Jenkins 📍 Accelerators - Data Quality, Data Curation, Data Catalog

Senior Developer with 10 years of experience in Deep Learning. I work with companies and startups on LLM based solutions, including: - text understanding including intent and requirements extraction from texts and validation AI-agents output against this requirements - AI-agent evaluation including such fuzzy problem as a validation of the LLM output - extracting company processes from logs and documentation and AI agent automation along this process - LLM fine-tune using most recent and advanced approaches. For agents evaluation it's useful to iterate on prompts quickly. I developed a pydantic based structured prompts solution to create prompts variation easily and open-sourced it in PromptBuilder library on GithHub. I have over 3 years of hands-on experience in LLM agent development. Previously In Deep Learning I have completed a multitude of tasks for clients in Computer Vision and NLP. In LLM area my portfolio includes fine-tuning LLM models like LLaMA 3 with synthetic dataset generation, creating chatbots and text analysis with simple RAG and Graph RAG approach. My strong skills are: following ML principles, precise planning and delivery. Following ML principles mean that I build a metric oriented pipeline and always choose reliable solutions. I possess a full stack skill set, from training models to their optimization and deployment. I follow with interest the progress in LLM on a daily basis and am ready to implement the new approaches. In terms of programming, I am a Full-Stack developer with a Computer Science background and a Master's Degree in Applied Mathematics and Informatics. My overall experience spans more than 12 years. I enthusiastically take on complex tasks and devise solutions based on my experience and understanding of AI development. Technologies and frameworks - PyTorch, Tensorflow - Onnx, OpenVino, NVidia Triton - MLflow - Vue.js Services and APIs - AWS & GCP administration - Azure API Programming languages - Python, Java, Kotlin, C++, Swift, TypeScript, SQL

I am a UK-based Senior Accountant and part-owner of a CIMA-regulated practice based in Bristol, providing compliant, commercially focused accounting and tax services to a portfolio of ~120 clients. Our practice delivers a full-service offering, including bookkeeping, VAT, payroll, statutory accounts, and tax optimisation (including capital allowances and allowable expense planning). We are Xero Advisor Certified and have over a decade of hands-on experience supporting owner-managed businesses across a range of sectors. What differentiates my work is the combination of regulated accountancy with advanced financial modelling and automation expertise. Since 2005, I have specialised in building automated financial models, reporting systems, and process-driven solutions using Excel/VBA, SQL, Python, and Google Apps Script. This allows us to go beyond standard compliance work—helping clients improve reporting speed, reduce manual errors, and make better financial decisions. I also lead on higher-value engagements including: - R&D Tax Credit claims - SEIS/EIS fundraising support - Bespoke financial forecasting and modelling In 2009, I developed an ICAEW-accredited financial forecasting platform designed to rapidly build integrated financial models. This reflects my broader approach: combining technical capability with accounting expertise to deliver solutions that are both compliant and commercially effective. Alongside practice work, I continue to support clients with bespoke modelling and automation projects across sectors, including construction & property, healthcare, FMCG, and financial services. I maintain a consistently high client satisfaction record by focusing on practical delivery, responsiveness, and long-term usability, ensuring clients receive support that extends beyond year-end compliance. I aim to ensure every client receives 5-star treatment, from project conception through to post-delivery support.

I focus on data engineering, software engineering, ETL/ELT, SQL reporting, high-volume data flows, and development of robust APIs using Java and Scala. I prioritize three key elements: reliability, efficiency, and simplicity. I hold a Bachelor's degree in Information Systems from Pontifícia Universidade Católica do Rio Grande do Sul as well as graduate degrees in Software Engineering from Infnet/FGV and Data Science (Big Data) from IGTI. In addition to my academic qualifications I have acquired a set of certifications: - Databricks Certified Data Engineer Professional - AWS Certified Solutions Architect – Associate - Databricks Certified Associate Developer for Apache Spark 3.0 - AWS Certified Cloud Practitioner - Databricks Certified Data Engineer Associate - Academy Accreditation - Databricks Lakehouse Fundamentals - Microsoft Certified: Azure Data Engineer Associate - Microsoft Certified: DP-200 Implementing an Azure Data Solution - Microsoft Certified: DP-201 Designing an Azure Data Solution - Microsoft Certified: Azure Data Fundamentals - Microsoft Certified: Azure Fundamentals - Cloudera CCA Spark and Hadoop Developer - Oracle Certified Professional, Java SE 6 Programmer My professional journey has been marked by a deep involvement in the world of Big Data solutions. I've fine-tuned my skills with Apache Spark, Apache Flink, Hadoop, and a range of associated technologies such as HBase, Cassandra, MongoDB, Ignite, MapReduce, Apache Pig, Apache Crunch and RHadoop. Initially, I worked extensively with on-premise environments but over the past five years my focus has shifted predominantly to cloud based platforms. I've dedicated over two years to mastering Azure and I’m currently immersed in AWS. I have a great experience with Linux environments as well as strong knowledge in programming languages like Scala (8+ years) and Java (15+ years). In my earlier career phases, I had experience working with Java web applications and Java EE applications, primarily leveraging the WebLogic application server and databases like SQL Server, MySQL, and Oracle.

I help companies turn complex, messy data into reliable, production-ready systems for analytics, reporting, and machine learning. I am a Senior Data Engineer and Cloud Engineer with over 8 years of experience building end-to-end data platforms, large-scale ETL pipelines, and cloud-native architectures on AWS and Azure. Most of my clients come to me when their pipelines are slow, expensive, fragile, or difficult to maintain. I design and rebuild data systems so they can run daily without breaking, handle growing volumes, and support real business decisions. I work across the full data lifecycle: ingestion, transformation, modeling, quality checks, and delivery. I build pipelines that pull data from APIs, databases, files, and event streams, transform it with Spark and SQL, and store it in data lakes and warehouses that power dashboards, analytics, and machine learning. I am AWS Certified and have built multiple production platforms using S3, Glue, EMR, Iceberg, Athena, Redshift, Lambda, IAM, and CloudFormation. I also have experience with Azure Data Factory, Databricks, and ADLS, as well as CI/CD tools such as Jenkins and GitHub Actions to keep data pipelines reliable and deployable. A strong part of my expertise is Spark and PySpark optimization. I regularly improve slow or unstable pipelines using techniques such as partitioning strategies, shuffle reduction, broadcast joins, caching, and breaking long DAGs with checkpoints. I have built highly optimized Spark pipelines processing millions of records daily in a stable and cost-efficient way. I have also implemented plug-and-play ETL frameworks that allow multiple teams to ingest and transform data from a shared repository, as well as data quality and ML monitoring using tools like Evidently to track drift and model performance. For business users and data science teams, I have delivered dashboards and reporting systems using Power BI and Amazon QuickSight. In addition to data engineering, I also have experience building web and mobile applications with React, which allows me to design data systems that integrate cleanly with real products and user interfaces. If you need someone who can not only write code but design, optimize, and operate serious data systems in production, I would be happy to help.

The Problem: Early-stage SaaS founders with ambitious AI ideas face a brutal reality, $200K+ team costs, 6+ month timelines, and infrastructure bills that burn through runway before finding product-market fit. What I Deliver: Production-ready AI/SaaS MVPs in 8-12 weeks at a fraction of typical costs, with serverless architectures optimized for your actual budget, not VC-funded dreams. Why Founders Choose Me Over Agencies or Hiring a Team 14 Years of Full-Stack + AI Expertise I'm not a specialist who needs a team. I handle Frontend (React/Angular), Backend (FastAPI/Python), DevOps (AWS serverless), and Data Engineering (RAG, vector DBs, pipelines). Zero coordination overhead. One person who owns the entire technical outcome. Entrepreneurial Mindset, Not Just Code Execution I don't just build what you spec, I identify features that can become revenue streams. Recent example: Turned a client's internal RAG tool into a sellable chatbot widget, creating a new business line they hadn't considered. Cost Architecture Obsession Your competitors spend $200K+ building AI features. I help you ship equivalent capabilities for $30-50K by ruthlessly optimizing cloud architecture and choosing the right tradeoffs for your stage. Recent Impact: RAG System for 80% Less Cost Client Challenge: Needed enterprise-grade RAG (Retrieval-Augmented Generation) for their chatbot but had limited budget and insisted on scalability. The open-source solution (Ragflow) wasn't designed for cost-efficient cloud deployment. My Solution: - Forked and reengineered Ragflow to run entirely on AWS serverless infrastructure - Built production stack: App Runner (backend), Amplify (frontend), Elasticsearch Cloud Serverless, Aurora, Batch, S3, ElastiCache - Designed chatbot widget and React application layer to productize the system Client Outcome: - $500K+ saved vs. hiring equivalent team (frontend, backend, DevOps, AI specialist) - 4 months from concept to investor-ready demo - Transformed cost center into potential revenue stream - Infrastructure costs: $300/month vs. $3-5K+ for traditional setup My Technical Stack - AI/ML: RAG implementation, LangChain, vector databases, prompt engineering, AI agent architecture - Backend: Python, FastAPI, Django, Scala, data pipeline design - Frontend: React, TypeScript, modern component architecture - Cloud/DevOps: AWS (Lambda, App Runner, Batch, Aurora, S3, ElastiCache), serverless-first architecture, Infrastructure-as-Code - Data: PostgreSQL, MySQL, Redis, Elasticsearch, large-scale data processing Who I Work Best With - Bootstrap-minded founders who need senior execution without senior salaries - Technical co-founders who need a force multiplier, not just another developer - SaaS companies adding AI features without ballooning their engineering budget - Anyone who values speed, cost-efficiency, and business thinking alongside technical excellence Let's Talk About Your MVP If you have an AI/SaaS idea and need someone who can architect, build, and deploy the entire solution without the overhead of managing a team, let's discuss whether we're a fit. Rate: $100/hour for focused, high-impact execution.

I am an Engineer who has multidisciplinary experiences and is expert in Big Data Processing and API Development. I am experienced in creating and implementing scalable data architectures, developing and optimizing ETL (Extract, Transform, Load) processes, and ensuring data quality and integrity. I am also experienced in developing APIs and providing the best solutions for the tech problems.

I'm a software engineer who works mostly with backend and scientific software development, including AI. I specialize in tackling complex, exotic projects that require creative solutions. - Bioinformatics tools and pipelines - Web service development - Database management - Genetic Algorithms - API Design and Implementation - Natural Language Processing - Stock and Crypto Trading Algorithms - Data Analysis and Visualization - C/C++/Rust scientific software development - Data Scraping / Crawling My languages of choice are Python/R/Haskell/Rust.

MSc. Data Science (Distinction), BSc. Chemical Engineering (Honours), former New Methods Data Scientist @ NIQ with 9+ years of well-established professional and academic track record. I specialize in machine learning research & model deployment, functional programming, statistical and mathematical computation, and business consulting. I'm highly technical and extremely rigorous while maintaining a personable touch through every client interaction, and have a proven track record in the petrochemical, market research, and consulting sectors. I selectively partner with clients, prioritizing high-profile projects that align with my expertise and pristine standards. ■ SOCIALS ───────────────────── ◉ LinkedIn: /in/pablo-aguirre-nunez ◉ GitHub: github.com/pabloagn ◉ Technical Blog: pabloagn.com ■ METHOD ───────────────────── ◉ I only deliver top-quality work and abstain from requests that trade quality for cheap solutions. ◉ I also abstain from requests that undervalue the task. (If the budget is constrained and you acknowledge this, I will take the case and propose a viable, realistic approach.) ■ TOOLS (I can attest to any expertise if required) ───────────────────── ◉ Programming Languages (General & Systems): ◎ Python, SQL, Julia, Rust, Go, C++, Java, Bash ◉ Functional Programming: ◎ Scala, Haskell, Nix, Lisps ◉ Data Science, Analytics & High-Performance Computing: ◎ Polars, Pandas, NumPy, SciPy ◉ Machine Learning, Modeling & Bayesian: ◎ Ray Ecosystem, JAX, PyTorch, TensorFlow, Scikit-learn, PyMC, Hugging Face Hub, StatsModels, MLflow, Kubeflow ◉ LLMOps, Observability & AI Tooling: ◎ LangFuse, Pydantic Ecosystem (Pydantic, Logfire, PydanticAI, Pydantic Gateway), Gradio, Prompt Engineering (Jinja2 templating), Experimentation & Evaluation Tooling ◉ Back-End, APIs & Systems Programming: ◎ FastAPI, Node.js, uvicorn, Inference Endpoints (Modal, Baseten), Dramatiq (task processing), Jinja2 templating ◉ Distributed Systems, Data Engineering & Infrastructure: ◎ Kubernetes, kind, Docker, Apache Airflow, Apache Spark (Scala, PySpark), Apache Flink, Apache Kafka, Terraform, GitOps (Argo CD), Linux (NixOS, Debian-based, Kali, Oracle Enterprise), Hadoop ◉ Cloud Platforms: ◎ AWS, GCP, Azure ◉ Monitoring, Logging & Observability Stack: ◎ Prometheus, Grafana, Loki, Promtail ◉ Databases & Storage: ◎ PostgreSQL, MySQL, MariaDB, MongoDB, Redis, Oracle DB, Qdrant, Azure Blob Storage ◉ Data Visualization & Reporting: ◎ Power BI (DAX, Power Query M), Tableau ◉ IaC & DevOps: ◎ NixOS, Nix Flakes, Terraform, GitHub Actions, CI/CD pipelines ◉ Prototyping & Front-End: ◎ Figma, Adobe Illustrator, React, Turborepo, pnpm, Streamlit ◉ Documentation & Version Control: ◎ Typst, LaTeX, Markdown, Git, GitHub ◉ Project & Workflow Management: ◎ Linear ■ INDUSTRIES OF EXPERTISE ───────────────────── ◉ Petrochemical ◉ Agricultural ◉ Financial ◉ Consumer and Retail ◉ Insurance ◉ Business Consulting ■ AREAS OF EXPERTISE ───────────────────── ◉ Behavior of complex systems and processes ◉ Mathematical modeling across diverse contexts ◉ Robust data analysis, interpretation, and validation ◉ Strategic consulting in technically complex fields ◉ Deep understanding of consumer behavior ◉ Cross-disciplinary collaboration and communication ◉ Abstracting business problems into computational solutions ◉ Designing, testing, and delivering complex systems to both technical and non-technical stakeholders ◉ Contributing to the open-source community through maintained projects and utilities ■ WAY OF WORK ───────────────────── ◉ We meet → I understand your business problem → I provide feedback and help manage expectations. ◉ If it’s a go and the timeline is realistic, we plan. Else, I assemble a bigger team with dedicated experts. ◉ I develop the solution → you provide feedback → I deliver the final version. ◉ We set short/medium/long-term maintenance support if required. ◉ We both win. ■ AVAILABLE UPON REQUEST ───────────────────── ◉ Verified credentials / CV ◉ A full Business Services Offering ◉ Previous work evidence ◉ References (Professional / Academic) ■ BUSINESS HOURS (BST) ───────────────────── ◉ Mon - Fri, 9:00 hrs - 19:00 hrs ◉ Sat, 9:00 hrs - 14:00 hrs Expected response time: ◉ During BD: 30 minutes ◉ Outside of BD: 2 hours Complexity, simplified. Let's work together.