With over 25 years in the database industry, I focus on SQL optimization, database performance tuning, and PostgreSQL consulting. Currently supporting Oracle-to-PostgreSQL migrations and troubleshooting complex database performance issues, I bring expertise in both on-premises and fully managed cloud environments. Leveraging deep skills in PostgreSQL, SQL tuning, and database optimization, my work aims to enhance the efficiency and reliability of OLTP and OLAP systems. Passionate about solving performance bottlenecks, I help organizations streamline database operations and achieve scalable, high-performing solutions.

.NET backend developer with 12+ years building production-ready APIs, SaaS platforms, and full-stack web applications. I turn complex requirements into clean, scalable code, on time and without hand-holding. Whether you need a REST API built from scratch, a third-party integration (payments, maps, messaging, or anything in between), or a full-stack .NET + React application, I'll bring both technical depth and real-world judgment to your project. What I work with: • Backend: .NET Core, .NET Framework, C#, REST APIs, Entity Framework Core • Frontend: React • Databases: PostgreSQL, SQL Server • Integrations: Twilio, Google Maps, OAuth2, payment processors, Azure What I've delivered: • Multi-tenant SaaS platforms with complex business logic • Full-stack applications with real-time third-party integrations • Admin dashboards and customer-facing web apps • Scalable API architectures for startups and enterprise clients I'm Top Rated on Upwork with a 100% Job Success Score. I communicate clearly, deliver what I commit to, and I care about the long-term health of your codebase, not just getting it done. If you need someone who can think through architecture and execute it end-to-end, let's talk.

It was the most important moment of my 13+ years of career. It was when I realized that there is always a trade-off in technology. You have to do something intentionally bad in order to succeed as a Small Medium Business in the Digital Transformation. And 70% fail because they insist on doing this very thing well. A while back, when I finally landed a job in a corporation, I was excited that I was going to use state-of-art technology. But, one of my first features immediately added some bugs. As I fixed those bugs, I introduced another, but also other bugs started to pop up caused by previous developers. In laymen terms, it is like a Rubik’s cube. As you carry on assembling the second face, you may accidentally mess up the first bit. It wasn’t like that when I started my career in technology in the civil service a long time ago. Yes, I was frustrated because we used old boring technology. But, we didn’t have to put out the fire all the time because that limited technology prevented us from getting in this position. Coincidence or not, the easiest way to solve the Rubik’s cube is putting constraints. If you move towards, you have to move backwards at some point. Fast forward to nowadays, some of my clients want to create highly customized User Experience. As the project starts to grow, hyper customization introduces more complexity. Then, you make a small change and get unexpected results. You didn't account for all the complex consequences. And this happens again and again, and you can’t avoid it. The software had become brittle. You start to miss deadlines or have to hire more developers to fix cracks faster, and eventually I get hired. That’s the time I have the hard talk: don’t bite more than you can chew, stop chasing the perfect User Experience (good User Interface is not a problem though) with a small team. If a BigTech didn’t have to hire thousands of engineers to provide that, they certainly wouldn’t. Anyway, User Experience is only noticed by B2C clients, and this is where Big Techs thrive. In B2B or internal tool software, who pays for the software won’t even use it. Hey, my name is João, I’m a software architect and developer, feel free to send me a message asking how I can make your business grow. What technologies do I work with? The simple ones: HTML, CSS, Bootstrap, Bash, XML, PostgreSQL, Apache Camel, Apache Knowledge Is Everything, Keycloak. If you need a hypercustomized solution, I can decently program in Java, Python and JavaScript, though. If you have any doubts, don’t hesitate to contact me.

Expert in relational database systems, especially PostgreSQL (Supabase, Amazon Aurora/RDS, Azure Hyperscale/CosmosDB/Citus, postgREST, RPC, RLS, timescaledb, PostGIS), MS SQL Server, and MySQL, with more than 27 years of experience as a database architect, designer, developer, and administrator. I’m also a software developer with 37 years of experience in many platforms, programming languages, and database systems. Expert in all of the following: * database installation, configuration, optimisation, securitisation, backups, performance improvement, encryption. * database design, SQL code optimisation, indices optimisation, coding stored procedures, increasing performance and security, partitioning. * data quality, de-duplication, normalisation, AI-assisted enrichment. * single and multi-tenant systems, JWT authentication, RLS authorisation. * REST and RPC functions, Edge/Lambda functions, Webhooks, AI APIs, Realtime, migrations. * database conversion or migration (e.g. to/from noSQL or JSON stores), interfacing with other databases, importing and exporting data, interfacing with online services (pl/perl, C, C#) * hot/cold backup and restore, recovery, replication (master/slave or master/master), mission critical * encryption in transit and/or at rest; encryption of data for authorised access only * text-file data extraction, formatting, conversion, archival, clean-up. Databases: PostgreSQL, SQL Server, MySQL, D3/Pick, Oracle, NexusDB, DB2, SQLite, COBOL, MongoDB, BerkeleyDB, Informix, Access, InterBase, Paradox, DBase/Clipper/Fox (DBF), CSV and plain text. Expertise with UAT/development/test environments, Regular Expressions (regex), batch and shell scripting, sed and other text processing tools, Excel, SOAP and web services, networking tools, and many programming languages (including Delphi, C/C++/C#, Perl, PHP, Smalltalk, Java, JavaScript, Python, and more). I can provide training and consultancy.

⚡ I build data warehouses that run faster and cost less. One client went from a $4,000 monthly bill to $40, with query times dropping from 84 hours to 2. I help SaaS companies, agencies, and data-heavy startups move off slow, expensive setups and onto Snowflake, BigQuery, and dbt pipelines they can actually trust. 𝐒𝐨𝐦𝐞 𝐨𝐟 𝐰𝐡𝐚𝐭 𝐈'𝐯𝐞 𝐬𝐡𝐢𝐩𝐩𝐞𝐝: ▸ Migrated 250 million records from PostgreSQL to Snowflake for a B2B data platform. Monthly cost fell from $4,000 to $40, query time from 84 hours to 2. ▸ Built the dbt and Snowflake pipeline behind an influencer dashboard serving Nike, Under Armour, and New Balance. Adding New Balance lifted annual revenue by $1.8M. ▸ Rebuilt the reporting layer for a coaching platform with 100,000 users, taking dashboard refresh from 4 to 6 hours down to near real time. ▸ Scraped 10,000+ restaurant outlets across DoorDash, Uber Eats, and Grubhub at over 98% success rate, feeding clean order data into BigQuery. 𝐖𝐡𝐚𝐭 𝐈 𝐝𝐞𝐥𝐢𝐯𝐞𝐫: ✔ ETL and ELT pipelines (Python, SQL) ✔ Cloud data warehouses (Snowflake, BigQuery, Redshift) ✔ Data migration and data modelling ✔ dbt transformations and Airflow orchestration ✔ Data ingestion (Fivetran, API integration) ✔ Web scraping and data extraction at scale (10,000+ sources, 98%+ success) ✔ Cloud infrastructure (GCP, AWS, S3, Lambda) ✔ Analytics and BI-ready datasets I'm a Google Certified Professional Data Engineer with a master's from Georgia Tech and 8+ years across these stacks. If your warehouse is slow or your bill keeps climbing, send me your current setup and I'll send back a FREE audit showing where the cost and time are going, and what I'd change first. SEE YOU IN CHAT!

Hello, everyone!🙌 If you have found my profile, it means you need a Full Stack developer with React.js, Next.js, Node.js, Express, Nest.js, JavaScript, TypeScript and other skills and expertise. Let me realize your needs and ideas! 🔥 My mission is simple - to bring your concepts to life with clean, efficient and user-centered applications, from intuitive front end interfaces to powerful back end systems. 🗝️ 𝙆𝙚𝙮 𝙥𝙤𝙞𝙣𝙩𝙨 • Fluent in English with strong communication skills • 3 years of experience as a Full-stack developer delivering high-quality solutions • Results-driven with reliable, timely delivery • Team collaboration expert • Client-oriented approach • Excellent time management ⛳️ 𝙏𝙚𝙘𝙝𝙣𝙞𝙘𝙖𝙡 𝙚𝙭𝙥𝙚𝙧𝙩𝙞𝙨𝙚 as a Full-stack developer ✓ JavaScript TypeScript ✓ ReactJS React-Storybook ✓ ReduxJS ✓ NextJS ✓ Material UI Ant Design Tailwind CSS ✓ styled-components ✓ SCSS Sass Less ✓ HTML5 CSS3 ✓ Charts chart.js recharts.js Apexcharts Highcharts ✓ Node.js ✓ Express.js ✓ NestJS ✓ Socket.io WebSockets ✓ MongoDB PostgreSQL Firebase Neo4j GraphQL Pinecone DB ✓ Sequelize TypeORM Stripe API Twilio API SendGrid ✓ CI/CD Docker ✓ GitHub Actions GitLab Bitbucket ✓ AWS EC2 Lambda API Gateway S3 RDS Cognito Elastic Beanstalk Cloudwatch IAM Amazon ✓ Web Services ✓ Algolia ElasticSearch RabbitMQ JWT Auth0 0Auth ✓ Testing Mocha Jest Supertest Postman My team and I work on web design, web and mobile development, and project management. Our developers are frontend developers, backend developers, fullstack developers, like me, and mobile application developers using Flutter and React Native. ➡️ Who are we? We are an INCODE Group. We develop world class web and mobile applications. We build an exceptional customer experience on both web and mobile platforms. We guide you from concept to a functional solution, all while meeting your deadlines. Our main services are Back End Development, Front End Development, User interface design services, and Mobile development. 🌟 𝘽𝙚𝙣𝙚𝙛𝙞𝙩𝙨 𝙞𝙛 𝙮𝙤𝙪 𝙝𝙞𝙧𝙚 𝙢𝙚 as a Full-stack developer: ♟️ 𝐒𝐭𝐫𝐚𝐭𝐞𝐠𝐢𝐜 𝗽𝐫𝐨𝐛𝐥𝐞𝐦-𝘀𝐨𝐥𝐯𝐢𝐧𝐠 - I turn challenges into opportunities. In addition to building applications, I develop customized solutions that increase real project value, whether I'm building something from scratch or enhancing existing systems, because I am a Full-stack developer. 🤝 𝐒𝐞𝐚𝐦𝐥𝐞𝐬𝐬 𝗲𝐧𝐝-𝐭𝐨-𝗲𝐧𝐝 𝗼𝐰𝐧𝐞𝐫𝐬𝐡𝐢𝐩 - From initial concept to deployment and beyond, I manage the entire development lifecycle with meticulous attention to detail, ensuring consistent execution and transparent communication at every stage. 🦾 𝐔𝐧𝐜𝐨𝐦𝐩𝐫𝐨𝐦𝐢𝐬𝐢𝐧𝐠 𝗾𝐮𝐚𝐥𝐢𝐭𝐲 𝘀𝐭𝐚𝐧𝐝𝐚𝐫𝐝𝐬 - Every line of code I write follows industry best practices - clean, documented, and built to scale. 💻 𝐏𝐫𝐨𝐯𝐞𝐧 𝗿𝐞𝐬𝐮𝐥𝐭𝐬 - As a skilled Full-stack developer, my work helps to develop a solution, website, application that engages users, is productive and efficient, which directly affects the profit received from the project and thus satisfies all the client's needs. ❓ What would you like to create or enhance? As a Full-stack developer, I would love to hear about it! 📬 ☎️ Specialization: nestjs, backend developer nest.js, next.js, react nextjs, react next, web developer, website developer, webflow developer, react web developer, web developer next.js, webflow, web design, website designer, aws, aws developer, supabase, customer support, n8n supabase, postgresql supabase javascript rest json, postgres, firebase, aws, aws devops, aws amplify, python aws, aws connect, aws docker, api integration, html css javascript, full stack developer aws, node.js aws, react next supabase ai aws, front-end developer full-stack, fullstack nextjs, fullstack typescript, fullstack python, fullstack developer figma mongo sql react next video streaming, full stack developer, full stack web developer, full stack developer ai, full stack developer react, full stack developer aws, mongodb, nodejs mongodb, next.js mongodb, back end developer node.js, back end web developer, backend engineer, backend, backend nodejs, express, adobe express, node express, backend developer nest.js, backend aws, backend next.js, backlinks, react node, full stack node.js react, node.js aws, full stack next.js, node.js next.js, front end developer, front end developer react, front end web developer, front end developer next.js, angular front end, framer, fractional cfo, react front end, react flow, react firebase, full stack developer react firebase, full stack developer react node, react native, react native mobile, react nextjs, react typescript

I build enterprise-grade .NET systems that businesses actually run on. Dynamics 365 CRM, SharePoint solutions, healthcare integrations, and accounting platforms built for real production load. 8 years doing this, not learning it. I currently work in an enterprise healthcare environment building HIPAA-conscious integrations and Dynamics 365 CRM systems that large teams depend on daily. The same standard applies to every project I take on Upwork. Backend: ASP.NET Core, .NET 8, C#, REST APIs, Microservices, Entity Framework, SignalR. Enterprise: Dynamics 365 CRM customization, plugins and workflow automation, SharePoint on-premises solutions, document libraries and governance. Healthcare: FHIR, HL7 and eCR integrations with HIPAA-conscious design. Frontend: React, Next.js, TypeScript. Database: SQL Server and PostgreSQL, design, optimization and administration. DevOps: Linux and Windows servers, Docker, Azure DevOps, Nginx, production API deployments. I deploy and operate what I build, not just hand off code. You can verify this right now: mobileinventory.store is a multi-tenant SaaS I built and run end to end. I tell you what is hard before we start, not after. If your project needs production-grade .NET, CRM, SharePoint, or healthcare integration work, let us talk straight about what it actually takes to get it right.

𝐅𝐮𝐥𝐥 𝐒𝐭𝐚𝐜𝐤 𝐄𝐧𝐠𝐢𝐧𝐞𝐞𝐫 | 𝐀𝐈 𝐅𝐢𝐫𝐬𝐭 𝐒𝐚𝐚𝐒 𝐁𝐮𝐢𝐥𝐝𝐞𝐫 | 𝟖+ 𝐘𝐞𝐚𝐫𝐬 | 5𝟎+ 𝐏𝐫𝐨𝐝𝐮𝐜𝐭𝐬 𝐒𝐡𝐢𝐩𝐩𝐞𝐝 𝐖𝐡𝐚𝐭 𝐦𝐚𝐤𝐞𝐬 𝐦𝐞 𝐝𝐢𝐟𝐟𝐞𝐫𝐞𝐧𝐭: I am AI enabled at the workflow level. I use advanced tools like GPT, Claude, Qwen, Kimi and Cursor to accelerate development, testing, documentation and automation. 𝐈 𝐡𝐞𝐥𝐩 𝐟𝐨𝐮𝐧𝐝𝐞𝐫𝐬 𝐭𝐮𝐫𝐧 𝐢𝐝𝐞𝐚𝐬 𝐢𝐧𝐭𝐨 𝐩𝐫𝐨𝐝𝐮𝐜𝐭𝐢𝐨𝐧 𝐫𝐞𝐚𝐝𝐲 𝐒𝐚𝐚𝐒 𝐩𝐫𝐨𝐝𝐮𝐜𝐭𝐬 𝐟𝐚𝐬𝐭. I build AI powered MVPs and scalable platforms using Python (Django, FastAPI) and React (Next.js). By combining clean architecture with AI assisted development workflows, I reduce build time by up to 40 percent without sacrificing quality. If you are building: • AI SaaS • Internal tools with automation • Custom CRM or dashboards • FinTech or subscription platforms • AI agents or LLM powered products I can help you ship faster and smarter. 𝐓𝐡𝐚𝐭 𝐦𝐞𝐚𝐧𝐬: • Faster iteration cycles • Cleaner architecture from day one • Rapid prototyping • Better code coverage and refactoring • Shorter time to MVP 𝐓𝐞𝐜𝐡 𝐒𝐭𝐚𝐜𝐤: 𝐅𝐫𝐨𝐧𝐭𝐞𝐧𝐝 - React.js, Next.js, TypeScript, Tailwind, Redux, Framer Motion 𝐁𝐚𝐜𝐤𝐞𝐧𝐝 - Python (Django, FastAPI, Flask), Node.js, Go 𝐀𝐈 & 𝐋𝐋𝐌 - OpenAI API, LangChain, Pinecone, Vector Databases, RAG systems, AI Agents, Custom Chatbots 𝐂𝐥𝐨𝐮𝐝 & 𝐃𝐞𝐯𝐎𝐩𝐬 - AWS (EC2, S3, Lambda), Docker, CI CD, DigitalOcean 𝐌𝐨𝐛𝐢𝐥𝐞 - React Native, Expo 𝐖𝐡𝐲 𝐂𝐥𝐢𝐞𝐧𝐭𝐬 𝐖𝐨𝐫𝐤 𝐖𝐢𝐭𝐡 𝐌𝐞: -Top Rated Plus, Top 3% on Upwork -6000+ hours completed -Full time freelancer, US business hours -Clear communication and realistic timelines -Long term collaboration mindset If you have an idea and need a technical partner who understands AI, architecture, and product thinking, send me a message. 𝐋𝐞𝐭’𝐬 𝐛𝐮𝐢𝐥𝐝 𝐬𝐨𝐦𝐞𝐭𝐡𝐢𝐧𝐠 𝐬𝐜𝐚𝐥𝐚𝐛𝐥𝐞.

Are your SQL queries running too slowly? Need help with ETL, reporting, or database migration? Looking for a reliable database expert who can solve problems efficiently and deliver clean, accurate results? I help businesses improve database performance, optimize SQL queries, build ETL workflows, and manage safe, accurate data migrations across SQL Server, Oracle, MySQL, and PostgreSQL. I can help with: • SQL query optimization and performance tuning • Stored procedures, functions, triggers, and packages • ETL development and data import/export processes • SQL Server, Oracle, MySQL, and PostgreSQL development • Data migration, validation, and transformation • SSIS, SSRS, and SSMS • Oracle Forms, Oracle Reports, BI Publisher, and Pro*C • Database troubleshooting, cleanup, and optimization I focus on practical solutions that improve speed, accuracy, and reliability. My goal is not just to write SQL, but to solve the business problem behind it. Why work with me? • Strong expertise across multiple database platforms • Oracle Certified Professional (Developer Track) • Master’s degree in Computer Science • Detail-oriented and quality-focused • Clear communication and dependable delivery I can support one-time fixes, ongoing database work, ETL projects, reporting solutions, and migration tasks. Let’s discuss your requirements and find the right solution for your project.

I am Data Architect/Snr. Data Engineer with 12 years experience with RDBMS/NoSQL databases and processing large amounts of data. My experience related to enterprise level and high profile projects in the past, but now I'm helping startups and small-mid sized companies to achieve their goals! My core competences are: Data Modelling, Data Architecture on Cloud platforms, Database development, ETL and Business Intelligence, Database Administration Solution Architecture : Design of solution architectures for a data processing systems of various scale and purpose. Definition of up-to-date technical solutions including data storage, network, data processing (ELT/ETL), BI and AI/ML components. Process and methods definitions and optimizations. AI/ML : Amazon AI Services, LLM Integration (OpenAI, Gemini), AWS Bedrock, AWS Sagemaker, pgvector, Databricks Mozaic Data Modelling : Modelling of OLTP and Datawarehouse systems. It could be design of new schema, normalization/denormalization of existing model, Enterprise datawarehouse design based on Kimball/Inmon, Data Lake and Data Vault architectures, Modernization of existing data landscape. Data Lakes : Modern datalakes built on cloud storages as GCS/S3/Azure Datalake Gen2 with Databricks, AWS Glue, Trino, Apache Iceberg DBA Activities : DB migrations, Backup & Recovery, Upgrades, Instance configurations, DB Monitoring, Horizontal scaling, Streaming/BDR replications. Sharding with postgreSQL extensions. Data Integration and ETL : Traditional batch ETL - Informatica, Talend, AWS Datapipeline, Matillion ETL Serverless ETL - AWS Lambda, AWS Glue, Batch, AWS DMS, Google Cloud Functions, Databricks Streaming ETL - Apache NiFi, Kafka, Kinesis streams SaaS ETL - Stitch, Alooma, Fivetran, Airbyte BI/data layers - dbt/Prefect Direct loading with DBMS tools & scripting Data Governance and MDM: Design and implementation of solutions based on Informatica DG/MDM, Alation, Atlan, custom dataquality solutions. BI Systems : Design of BI systems and implementation. I had experience with major industry leading tools as Tableau, PBI, Looker and cloud alternatives. Additionally i had experience with old-style reporting solutions from SAP, Qlick, Jasper. Cloud containerization and deployment : Docker, Mesos/Kubernetes Java development : EE/SE , Spring, Hibernate, RESTful APIs, Maven Clouds : - Cloud migrations (AWS, Azure, GCP) - Cloud infrastructures (VPCs, EC2, Loadbalancing, Autoscaling, Security in AWS/GCP) Please note that minimum engagement is part-time (20 hrs/week) and month long, this will ensure the quality of delivered solution and mutual benefit. Thank you for getting to the end of this boring details and looking forward working on exciting projects together :) Best Regards, Yegor.