I help startups and growing businesses turn ambitious ideas into production-ready, AI-powered applications — and I love every part of that journey, from architecture to deployment. With 5+ years of hands-on software engineering experience, a Bachelor's in Software Engineering, and a Master's underway in Machine Learning & Distributed Systems, I bring both academic depth and real-world enterprise experience to every project. I've built HIPAA-compliant healthcare platforms processing real-time clinical data, engineered LLM-powered backend systems with Retrieval-Augmented Generation (RAG) pipelines, and designed high-throughput data pipelines using Kafka, MongoDB, and ClickHouse. Whatever stage your product is at, I can help you get there faster and more reliably. Skills & Specializations: • Enterprise Web Applications — MEAN & MERN stacks (Angular, React, Node.js, Express) • AI & LLM-Powered Solutions — chatbots, virtual assistants, RAG pipelines, intelligent automation • Microservices & Backend APIs — FastAPI, Node.js, event-driven architecture, Kafka • Data Engineering & Analytics — Kafka, MongoDB, ClickHouse, Apache Superset, PostgreSQL • Cloud & DevOps — AWS, Docker, CI/CD pipelines, monitoring & logging • System Design & Architecture consulting for startups and growing teams Why clients enjoy working with me: • Clean, maintainable code built for long-term scale • Clear communication and a structured, transparent delivery process • A problem-solving mindset — I dig into complex challenges and simplify them • End-to-end ownership, from idea to deployment and beyond I'm excited to bring the same energy and rigor I use on enterprise healthcare and AI systems to your project. Let's talk about what you're building — I'd love to help you move it forward.

I build and optimize databases that hold up under real production load and turn raw data into reporting that actually answers business questions. Over 6+ years I've worked as a database developer and engineer across gambling, healthcare, and banking. Most notably, I spent 6 years with Flutter (the group behind FanDuel, Paddy Power, and Betfair), where I designed and built Oracle/PostgreSQL database objects from scratch - packages, procedures, functions, triggers - for revenue-critical promotional systems, achieving 4x performance gains through indexing, partitioning, and query rewrites, and later built ETL pipelines (Apache NiFi, ClickHouse, BigQuery) feeding BI reporting. I've also architected a centralized MySQL schema for clinical-trial data at a healthcare client, improving data extraction speed by 80%, and earlier built IFRS-compliant regulatory reporting for a bank and executive Tableau dashboards for another. I hold a Master's degree in Information Technologies and I'm comfortable across PostgreSQL, MS SQL Server, Oracle, MySQL, and ClickHouse. What I can help with: • Complex queries, stored procedures, functions, triggers, and scheduled jobs • Database schema design and performance optimization (indexing, partitioning, query rewrites) • ETL pipelines and data warehouse builds (Apache NiFi, BigQuery, ClickHouse) • Translating business requirements into technical specs I'm newer to Upwork specifically, but not new to this work if you need a database built correctly the first time, or an existing one cleaned up and made fast, let's talk about what you're working on.

Hi! I am a Data Analyst & Excel Specialist focused on automating routine tasks and turning messy data into clear, actionable insights. If your business is drowning in disorganized spreadsheets or you need to extract specific reports from your database, I am here to help. What I can do for you: • Advanced Excel & Google Sheets: Complex formulas (VLOOKUP, INDEX/MATCH), pivot tables, data cleaning, and formatting. • Data Transformation: Merging, deduplicating, and normalizing messy data from CRM/ERP systems into clean, structured tables. • SQL Scripting: Writing efficient SELECT queries, JOINS, and aggregations to extract data from PostgreSQL or MySQL databases. • Automation: Streamlining repetitive manual reporting processes to save your time. I have strong analytical thinking, attention to detail, and a structured approach to problem-solving. My goal is to make your data work for your business efficiency. Let’s connect and discuss how I can optimize your data workflows!

I am a Senior Data Engineer with 5+ years of experience delivering production data systems in large product companies and client projects. My work covers the full path from APIs and operational databases to analytics-ready models: ingestion, ETL/ELT, orchestration, batch and streaming processing, data quality, observability, and performance tuning. I take focused assignments where an experienced engineer is needed to build or repair a pipeline, integrate a data source, redesign a data model, or stabilize an existing workflow. I work independently and leave behind maintainable code, documented technical decisions, and a clear handover. Main stack: Python, SQL, Airflow, dbt, Kafka, ClickHouse, PostgreSQL, and BigQuery.

I build, repair and optimise production data pipelines, warehouses and migrations. My core stack is Apache Spark, Scala, PySpark, SQL, Airflow, Kafka/Spark Streaming, Hadoop/Hive/Iceberg, and PostgreSQL, ClickHouse, Greenplum and Oracle. I can help with: • Spark pipelines, reusable frameworks, JAR/Wheel packaging, Spark UI debugging, joins, skew, shuffle, partitions and memory issues • Airflow DAGs, custom operators/hooks, retries, backfills, sensors, templating and concurrency • batch and streaming ingestion with Kafka and Spark Streaming • SQL schema design, data loading, indexes, execution plans and performance tuning • data modelling, SCD Type 2, reconciliation, validation, migration checks and data-quality controls • Docker/GitLab CI delivery and practical monitoring with Grafana and existing Prometheus metrics My enterprise background includes Spark/Hadoop warehouse delivery, legacy migration, metadata onboarding, production data-quality work and cross-layer incident resolution. I also build products: Flatsearch has processed 16M+ listing observations; I published JetBrains developer tools and three Android apps on Google Play. A supporting example of my migration work is a published Scala/Spark library for Oracle-to-Hive extraction. It uses Oracle data-dictionary metadata, ROWID-based parallel JDBC ranges, a consistent Flashback SCN and explicit Oracle-to-Spark/Hive type mapping. I use this depth for relevant migration work rather than presenting it as my only service. You receive clear scope, maintainable code, explicit assumptions, reproducible validation and practical handover. Send the source and target systems, approximate volume, current failure or bottleneck and the result you need.

I build AI that lets people ask questions of their own data in plain English and get real answers. That's the work I do best: taking a company's data and turning it into something anyone can just ask a question of, with answers grounded in their real data instead of guessed. What I can build for you: • Chat-with-your-data agents that answer plain-English questions from your database, warehouse, or documents • The data pipeline and warehouse that feed them (Postgres to ClickHouse, serverless ETL) • The guardrails demos skip: per-tenant security, cost controls, and usage tracking • A real, shippable product (Next.js/React), not just a notebook prototype • Rescue work: making a shaky AI prototype reliable, secure, and affordable to run Most "AI developers" can wire up a demo. I recently architected and built a multi-tenant AI analytics product that does all of the above, now in beta with its first external customer. I've built the full stack for 30 years, including video technology adopted by Apple (QuickTime) and Adobe (Flash), 11 U.S. patents, and the engineering behind a company that grew past $1B. If that's the kind of build you need, let's talk.

Full Stack Mobile Developer | Flutter, Android,Backend Solution, React Native, Python, FastAPI, LLM & RAG Solutions With 10+ years of experience in mobile and full-stack development, I have successfully delivered 30+ production applications and contributed to hundreds of projects for clients across healthcare, real estate, e-commerce, logistics, education, social networking, HR, and SaaS industries. I specialize in building scalable business solutions using Flutter, Android (Kotlin/Java), React Native, Python, FastAPI, Node.js, and modern AI technologies including LLM integration, RAG (Retrieval-Augmented Generation), vector databases, and LangChain. Currently, I lead Mobile & AI Engineering teams, architecting enterprise-grade applications and AI-powered platforms for international clients. My expertise spans the complete product lifecycle—from planning and architecture to development, deployment, and long-term maintenance. Key Expertise: • Mobile App Development (Android, Flutter, React Native, iOS) • AI-Powered Applications (LLMs, RAG, Prompt Engineering, Vector Databases) • Backend Development (Python, FastAPI, Node.js, REST APIs, WebSockets) • GIS & Map-Based Applications (Google Maps, Mapbox, WMS, Vector Layers) • SaaS Platforms & Enterprise Solutions • Real-Time Systems, Analytics & Tracking Applications • E-commerce, Healthcare, Education & Logistics Platforms • CI/CD, Agile Development & Team Leadership Notable Projects: ✔ AI-powered real estate search platform using LLM + RAG architecture ✔ GIS-based property mapping and valuation system ✔ Multi-vendor delivery platform with real-time GPS tracking ✔ Healthcare platform for online consultations and medical records ✔ Social networking platform with video sharing and monetization ✔ HR management and employee analytics systems ✔ School and coaching ERP solutions As a Team Lead and Senior Engineer, I focus on writing clean, maintainable code, delivering projects on time, and building solutions that generate real business value. If you're looking for a reliable developer who can handle everything from mobile apps and backend systems to AI integration and scalable architecture, I'd be happy to discuss your project.

Is your Laravel or PHP app slow, buggy, or breaking in production? Need a clean REST API or a Stripe payment integration that actually works the first time? That's exactly what I do. I'm a PHP & Laravel developer focused on reliable backends, REST APIs, and payment integrations and on rescuing projects when something's gone wrong. What I can do for you: Custom Laravel & PHP web application development REST API development + third-party API integration Stripe & payment gateway integration — checkout, subscriptions, webhooks Bug fixing & debugging for broken or unstable Laravel apps Performance & speed optimization — slow queries, caching, load time MySQL database design, optimization & migrations Why clients work with me: I find the root cause, not just a quick patch Clean, maintainable code that won't break your other features Clear, regular updates — you always know where things stand I don't stop until your problem is fully solved My tech stack: PHP, Laravel, REST API, MySQL, Stripe, Eloquent ORM, Blade, JavaScript, Git, Composer, third-party API integration, payment gateways, performance optimization. Broken checkout, a slow app, a messy API, or a full Laravel build from scratch — send me a message describing your problem and I'll reply with clear, honest recommendations. I usually respond quickly.

I'm a Backend Engineer specializing in Java and Spring Boot, with 3+ years of experience building scalable, reliable backend systems and APIs. I currently work on production systems in the last-mile delivery and logistics domain, where I've built and worked on systems handling 15K+ orders/day across 1,500+ riders and 26 warehouses. My strongest areas are: Java & Spring Boot backend development REST API and microservice development Distributed and event-driven systems AWS (SQS, SNS, DynamoDB, S3) Redis, MySQL & PostgreSQL Real-time data processing and operational dashboards Database design and performance optimization I've built systems for rider allocation, rider payouts, workforce management, real-time rider tracking, delivery workflows, and operational analytics. I've also worked with ClickHouse for high-volume analytics and event processing. � Sachin_3.6_Years_Expieriance.pdf Before my current role, I worked at TransUnion building Java/Spring Boot backend services and REST APIs, including a data validation platform and high-performance data processing pipelines. I also migrated a PySpark pipeline to BigQuery, reducing processing time by 95%. � Sachin_3.6_Years_Expieriance.pdf I can help you with: • Building backend APIs and services from scratch • Adding features to existing Spring Boot applications • Designing microservices and event-driven workflows • Integrating AWS services and databases • Debugging and optimizing backend systems • Building backend systems for logistics, delivery, and operations platforms I focus on writing clean, maintainable, production-ready code and understanding the business problem before implementing the solution.

With over 10 years of experience in systems administration, DevOps, and backend development for high-load platforms, I help businesses design and build resilient, distributed architectures. My background includes years of working on high-scale IoT/telematics systems, which gives me a deep understanding of how to handle millions of concurrent messages and maintain 99.9% uptime. What I can help you with: • High-Load Architecture: Designing scalable, cluster-native systems from scratch using the JVM reactive stack. • Monolith to Microservices: Deconstructing legacy applications into clean, maintainable, and reactive services. • Akka/Pekko Ecosystem: Building systems with Actor Model, Streams, Cluster, Sharding, and CQRS/Event Sourcing. • Infrastructure & DevOps: Bridge the gap between code and production. I configure CI/CD pipelines, optimize database performance (ClickHouse, PostgreSQL, Cassandra), and manage deployments on Linux/Kubernetes. My Technical Stack: • Languages: Java (up to 21), Scala • Frameworks: Apache Pekko / Akka (Actors, Streams, Cluster, Persistence), Spring Boot, Spring WebFlux • Databases: PostgreSQL, Cassandra, ClickHouse, MySQL • DevOps: Linux (Debian/CentOS), Docker, Kubernetes, Helm, CI/CD pipelines Whether you need to migrate a legacy system, optimize your database bottlenecks, or build a scalable real-time streaming platform from scratch, I am ready to assist.