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⚡ $170k+ on AI SaaS & Agents | 🚀 16 yrs in tech | 🤖 27 AI systems launched | 🛠 51+ products built I help companies build practical AI products fast - from MVPs and internal tools to scalable agent-based SaaS LLM platforms. Deep experience integrating GPT, Claude, Gemini, and Perplexity APIs into production systems using LangChain, Agent SDK, Langfuse, and custom orchestration logic. My typical stack includes FastAPI + Python + Supabase for backend systems and ReactJS for scalable front-ends. I focus on launching MVPs fast and turning them into production-ready AI products. I’ve earned $100k+ on Upwork delivering complex AI SaaS platforms and agent-based systems for founders and teams - from MVPs to long-term scalable products. Most projects involve complex business logic, multi-system integrations, and product-level architecture thinking. I work independently and lead a small engineering team when project scale requires it. 🧠 What I build • AI SaaS platforms with multi-tenant architecture and decision engines • LLM systems with RAG, memory, scoring, and structured outputs • AI tools for sales, procurement, analytics, and infrastructure 🏗 Industries • Real estate & PropTech - USA, Canada, Australia • Automotive & marketplaces • Sales-driven and data-heavy products Open to other domains with non-trivial problems. ⭐️ Selected recent projects • Multi-tenant AI Brokerage Platform - white-label SaaS with tenant isolation and AI listing scoring • AI Tender Evaluation System - weighted scoring + RAG-based compliance validation • B2B Opportunity Intelligence Platform (USA) - AI-driven pre-sales company research, opportunity scoring, and sales training system for enterprise deal preparation • AI Real Estate Matching Platform - multi-agent property search with semantic filtering and lead scoring 🔧 How I work 1️⃣ Define the real problem and success metrics 2️⃣ Design system architecture first 3️⃣ Build in milestones with early usable results 4️⃣ Deliver production-ready systems with clean handoff 🛠 Tech Python • FastAPI • LLMs (GPT, Claude, Gemini, Perplexity) • LangChain • RAG Supabase • PostgreSQL • Vector databases CRM & tools: Zoho, Airtable, Notion, Google Sheets Automation tools (incl. n8n) only when they make sense, not as a core focus. If you need someone who thinks like a product owner and delivers like an engineer - let’s talk ✉️

Results-driven system developer with more than 10 years of development experience using java. Having a strong technical background who possesses self-discipline and the ability to work with the minimum of supervision. Able to play a key role throughout the software development / support life cycle of a project to ensure the quality solutions meet business objectives. Also highly accomplished with a verifiable track record in fields such as analysis and gathering, business process mapping and the development of interactive prototypes.

I am a Java Web Developer, working as freelancer, mainly in Upwork. I am very passionate with Java and JVM technologies. My experience mostly in developing Software As A Service (SaaS) platform, business computing and information system area, using Bootstrap, Angular JS or JSF as UI Components or web framework, Spring Core, Spring MVC or JBoss Seam as Restful API endpoint and or Integration framework, and Hibernate as favorite Java Persistence API (JPA) implementation wrapped by Spring Data component. If my clients requires no casual application or web server, I like to use Spring Boot for simpler development and deployment of the application. I am also interested in database design and software design. I believe that great software not only mediocre work of typing, but also comes from thoughtful process. I believe in TDD, and also believe that tests code must be written, organized as good as the source code it self and is integral part of the source code. I am a quick learner, and In my spare-time, I am writing some personal open source project and small proof-of-concept about java-related stuff in my GitHub public repository. My primary machine is linux desktop with 1TB NVMe SSD and 64GB or RAM. I have macbook pro 15 for testing purpose and to allow me mobile occasionally, if needed. Communication is important in remote work, and for this purpose I have 2 link dedicated internet connections to my workspace. If you need my detailed skill abilities, below is what I have experienced in: - Software Design, Database Design, and microservices/Micro-services/micro services architecture. - JPA 1.0, JPA 2.0, with Hibernate. - Bean Validation Specification with Hibernate Validator. - Dependency Injection with Java DI (JSR-330), Java Context and Dependency Injection for Java EE Platform (JSR-299), and Spring Core as most popular (but non-standard) Java Dependency Injection Framework. - Java Web Framework with Spring MVC and JSP, or Java Server Faces (JSF) with Facelet and Primefaces. - Spring Boot, Spring Data stack. - Generated / scaffolding web application using JHipster. - Java Web / Application server with Tomcat, Wildfly, or Websphere AS. - Logging with SLF4J as a wrapper to Log4J or Logback. - JUnit or Test NG as testing framework. - Ant, Maven or Gradle as build and dependency management tool. - HTML 5, CSS 3, JavaScript, JQuery, Twitter Bootstrap, transparency.js, and angular / angular.js - Third Party API such as Xero API, Open ERP Java API, Braintree Payment API, Stripe Payment API, and Social APIs. - Linux, Mac or Windows. - MySQL, PostgreSQL, Oracle, or Microsoft SQL Server for RDBMS. - Couchbase or Mongo DB for No-SQL solution. - Elasticsearch (ELK) stack or pentaho for data integration, advanced search, reporting and data analysis solution. Thanks, Resa

8+ years of professional experience delivering production software across Desktop, Android, Web, and Embedded/IoT - for industrial, research, and hobbyist clients. Top Rated Plus with $300K+ earned and 11,000+ hours on Upwork. I work as a generalist who ships end-to-end: from PCB and firmware up to dashboards, mobile apps, and cloud integrations. I also leverage modern AI-assisted development (Cursor, Claude, Copilot) to ship faster without compromising quality - pairing it with strong fundamentals in C/C++, debugging, and architecture. What I can build for you: - Cross-platform Desktop apps - Qt, .NET (C#/VB.NET), C++ - Android apps - Java/Kotlin, BLE, GPS, hardware integration - Web apps & dashboards - JS/TS, REST APIs, IoT dashboards, Webflow CMS - Embedded & IoT - AVR, ARM, ESP32/ESP8266, Arduino, Embedded Linux - PCB Design - KiCAD, Eagle, EasyEDA - Connectivity - MQTT, BLE, LoRa, GPRS, RF, TCP/IP, RabbitMQ Languages & tools: C, C++, C#, VB.NET, Java, Python, Go, Swift, JS - Qt, .NET, Android Studio, PlatformIO, Xcode - MySQL, SQLite, JSON - Linux, Windows, macOS, Embedded Linux, Android. Long-term collaborations welcome - I'm currently supporting multiple clients on monthly retainers (sensor monitoring, IoT dashboards, embedded device support). Let's talk about what you're building.

I'm a skilled Software Engineer and Team Lead with expertise in web and mobile app development, backend engineering, and e-commerce solutions. With years of experience building custom websites, scalable APIs, and robust applications, I deliver clean, maintainable code and client-focused solutions tailored to your business needs. Proficient in technologies like Ruby on Rails, React, and TypeScript, I’m passionate about creating high-quality, innovative digital products that make an impact. Let’s work together to bring your ideas to life!

I have a substantial learning curve that allows me to continue other developer jobs or unfinished projects.  Familiar with backend Api using firebase or JSON REST API. Experienced worked both individually or in a team using Jira, Notion, CI/CD tools, and Github. Feature Developed in Flutter (Using various state management bloc, provider, stacked): 1. Data stream integrations from firebase using auth, functions, configs, firestore, and storage 2. Stripe Payment integrations (CC, grabpay) 3. Popular Indonesia payment gateway (midtrans to support gopay/shopee) 4. Chat Feature 5. Online Shopping Feature 6. Social media feature (comments, like share, follow) 7. Twillio chat and video room 8. Geolocation and map feature 9. Image manipulation 10. Real-time chat and voice using the agora 11. In APP purchase I have developed some production Apps. You can see my work detail in the portfolio.