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📣 FREE technical consultation (details below) 🐻 Proud UC Berkeley graduate (Applied Mathematics & Economics) and an entrepreneurial, reliable full-stack software developer with broad expertise across modern technologies (listed below). 💪💪💪 With experience as: • Full-Stack Team Lead at Camping World, a publicly traded company • Lead Technical Teaching Assistant at Hack Reactor, a leading software engineering bootcamp • Founder of Atini Studio, a high-performance software development agency With years of experience working with clients and leading engineering teams, I prioritize accountability, clear communication, and efficient execution. 🌈🌈🌈 I’m the founder of Atini Studio, a vibrant software development agency and a team I like to call software doctors: highly skilled engineers and creative UI/UX designers who diagnose, fix, and elevate digital products. ⌨️⌨️⌨️ What I help clients with: 📌 MVP development for startups 📌 Full-stack web applications 📌 Cross-platform mobile apps 📌 AI-powered features & integrations 📌 Clean implementation from Figma to production 📌 API integrations (Stripe, OpenAI, Google, Zoom, etc.) 📌 Performance optimization 📌 Technical architecture planning 📌 Product roadmap & scaling strategy We also leverage AI internally to accelerate development workflows and improve efficiency, so you get faster delivery without sacrificing quality. 🧩 Complimentary Technical Consultation Not sure how to move forward with your product? I can help you clarify: • The right tech stack • MVP scope • Timeline and budget expectations • System architecture decisions • Whether your current product is built correctly I offer a complimentary strategy session to help you create a clear and practical execution plan. 💻 Tech Stack: • Front End JavaScript | TypeScript | React | Next.js | React-Native | Angular | Vue.js | Tailwind CSS • Back End Node.js | NestJS | Python | Django | PostgreSQL | MongoDB | MySQL | ORM | GraphQL • API Integrations ChatGPT / OpenAI | Stripe | Google | Zoom | and more... • DevOps Amazon Web Services (AWS) | Firebase/GCP(Google Cloud Platform) | Azure | Docker • Testing Jest | Mocha | TDD • Developer Tools Git | npm | Webpack | Babel | Agile Methodology | Nginx • Design Adobe XD | Figma

I'm a seasoned software engineer with deep expertise in Unity and C#, specializing in game development and integrating gameplay systems. My work has been recognized by industry leaders, including Activision. This recognition underscores my ability to deliver innovative game solutions that exceed client expectations. I'm eager to bring this level of excellence to meet and surpass your needs! Skills & Expertise: 👨‍💻 Unity development: Unity scripting (C#), asset integration, mobile app development, performance optimizations, game mechanic/systems integration, game bug fixes, and RESTful API Integrations 🛠️ Version control software: Git, GitHub, Unity Version Control 🛜 Networking libraries: Photon Fusion, Mirror Networking, PUN2 🔧 Unity integration services: IAP & app advertising SDK integrations 🚩 Project management tools: Jira, Trello, Azure Boards, Confluence 🧩 Genres: FPS/TPS, match-3 puzzle, MMORPG, racing, top-down shooters, and open to expanding more! ⚙️Back-end services: Google Cloud Firestore for Firebase, Google Cloud Storage for Firebase, and Supabase 🧭 Perspectives: 3D & 2D I can implement solutions to accelerate your project and go beyond your expectations. I have worked with various clients and carved out project deliverables using the skillsets mentioned above. What I aim to bring to my client's project: ⏳ Timely deliverables meeting your direct needs, adjustments, or improvements 📞Clear and constant communication on my latest status for your milestone 👨‍💻 Professionalism in quality software development 🤝 Cooperation on the highest level to ensure you feel comfortable throughout our partnership ⏱️ Respect your time and perspective to ensure deadlines are met reasonably I will develop code for you that is clean, readable, portable, and maintainable. I always do my best to follow SOLID, DRY, and YAGNI software design principles and will adapt to any coding preferences, principles, or design patterns on a team or with you.

I build production web apps for founders and small teams, especially AI products, SaaS platforms, dashboards, automations, and payment-backed systems. Clients hire me when they need someone who can take plain-English specs, make good technical decisions, ship quickly, and communicate before they have to ask. What I build: • AI search and LLM workflows: vector search, embeddings, Pinecone, LangChain, OpenAI, Gemini • SaaS platforms and dashboards: auth, roles/RBAC, admin panels, reporting, realtime data • Payment-backed apps: Stripe billing, subscriptions, webhooks, checkout flows • Production frontends: React, Next.js, TypeScript, Tailwind CSS, PWAs • Backends and data: Node.js, Python, FastAPI, Firebase, Supabase, PostgreSQL Recent work includes: • AI real estate search using listing data structuring, natural-language filter mapping, Pinecone semantic search, and LLM pipelines • A gamified MMA gym management PWA with Stripe billing, realtime logic, and 800+ automated tests • A clinical documentation MVP for psychiatric workflows • A football playbook learning platform with a custom React/canvas builder, quiz engine, and AI-powered evaluation • Construction and field reporting tools for operational teams Clients describe me as fast, autonomous, clear, accountable, and quality-focused. I’m especially useful when you have the product vision but need a developer who can turn it into a real system without daily micromanagement. You’ll get: • early deployed previews • direct updates and honest scope calls • clean repo handoff and documentation • practical technical choices, not over-engineering • production-minded QA around auth, payments, webhooks, data, and edge cases If you’re building an AI product, SaaS MVP, internal tool, dashboard, or payment-connected web app, send me the idea. I’ll tell you clearly what I’d build first, what I’d avoid, and whether I’m the right fit.

Top Rated Plus Full Stack Mobile App Developer | Top 3% UpWork Talent | Flutter | Kotlin | Swift | React, Node.js, AWS | Building Scalable Digital Experiences I’m a passionate and detail-oriented Full Stack Developer with over 10 years of experience crafting high-quality Web and Mobile applications for startups, enterprises, and agencies worldwide. I specialize in building end-to-end solutions using modern technologies and frameworks — from beautiful, responsive UIs to robust, scalable backend systems. 💡 Tech Stack Highlights: Frontend:Flutter (Dart), React-Native, Kotlin, Swift, React.js, Tailwind CSS, TypeScript Backend: Node.js (Next.js, NestJS), GraphQL, REST APIs Database:, MySQL, MSSQL, MongoDB, Firebase, Google Cloud DevOps/Cloud: Docker, GitHub Actions, AWS (EC2, S3, Lambda) Tools: Git, Jira, Notion, Postman, CI/CD, WebSockets, Stripe, OAuth2 What I Offer: Full-cycle Development from concept to Deployment Clean, maintainable, and scalable code Mobile-friendly, SEO-optimized, and fast-loading applications API integrations (Stripe, Twilio, Firebase, third-party REST/GraphQL) Agile collaboration with clear communication and on-time delivery I’ve completed a wide range of freelance projects: custom dashboards, SaaS platforms, eCommerce sites, API backends, mobile-first apps, and admin panels. Whether you're looking to launch an MVP, optimize an existing product, or scale your system, I bring technical expertise and business acumen. ✅ Why Clients Choose Me: Strong work ethic & attention to detail Fast learner and great problem solver Transparent and clear Communication Available for one-time projects or long-term collaboration Let’s build something amazing together. Drop me a message — I’d love to hear about your project!

I build AI-powered apps — mobile and web — that solve real business problems. Expertise in Flutter and Next.js on the front, Supabase (Postgres, Realtime, Edge Functions, RLS) on the back, and AI integration (Claude, OpenAI) throughout. I deliver production-ready apps in weeks, not months. What I bring: real-time data sync (Supabase Realtime), full-stack delivery (Flutter/Next.js to Supabase Postgres to Edge Functions), and seamless AI integrations — LLMs, speech-to-text, image recognition, and face detection. Comfortable with Stripe payments, Firebase, and load testing at scale (50 concurrent users). Recent work: OneMind, a real-time AI consensus platform shipped on both Flutter and Next.js (1,388+ tests); an AI calorie tracker with photo recognition; and a biometric identity system using AWS Rekognition. I currently maintain several production apps for ongoing clients. Let's talk about your project — I respond within hours and scope accurately.

Most mobile apps in healthcare, wellness, and fitness don't fail because of missing features. They fail because they can't handle real-world usage. Slow screens. Broken sync. Unreliable data. And once users lose trust in a health app, they don't come back. That’s usually the moment I get involved. I'm a Senior Mobile App Developer with 15+ years of hands-on experience delivering iOS, Android, and cross-platform apps in healthcare, wellness, fitness, and connected systems where reliability matters as much as innovation. I don’t build quick demos; I build mobile systems that hold up under daily real-world use. A lot of my recent work sits at the intersection of mobile + healthcare + AI + GPS + connected devices. I’m selective about where intelligence and automation go. Features only stay when they improve outcomes or reduce friction. 📱 Mobile Development Expertise • Cross-Platform: React Native, Flutter (production apps) • Native iOS: Swift, SwiftUI, iPad apps • Native Android: Kotlin, Android features • Hybrid/Web: Ionic, WebRTC Focus Areas: • Real-world performance under heavy load • Offline-first systems, sync reliability, and state consistency • Clean, modular architecture • App Store & Google Play readiness 🗺️ GPS & Location Systems I build reliable location-based mobile systems that work in real conditions: • Real-time GPS tracking and route mapping • Background location tracking (battery-optimized) • Geofencing and location-triggered actions • Live location sharing • Fitness route tracking (running, cycling, walking) • Map integrations (Google Maps, Mapbox) These systems are designed to stay accurate even with weak signals, offline usage, and device restrictions. 📡 BLE & IoT Connected Systems I specialize in Bluetooth Low Energy (BLE) and IoT integrations where mobile apps connect to devices and sensors. • BLE device pairing and real-time communication • Wearable integrations (health & fitness tracking) • IoT systems using AWS IoT Core and Azure IoT • Sensor data streaming and sync • Background reconnection and stability handling I focus heavily on reliability: stable connections, clean reconnection logic, and consistent data sync. 🏥 Healthcare, Wellness & Fitness This is where most of my work lives: • Health tracking: vitals, symptoms, dashboards • Fitness apps: workouts, habits, progress systems • Wellness apps: journaling, meditation, mental health flows • Telemedicine: messaging, video consults, scheduling • GPS fitness tracking with real-time route analysis • Wearable + BLE health device integrations 🧠 Smart AI Integration AI is only used where it adds real value: • Personalized fitness and wellness insights • AI coaching and behavioral summaries • Journaling and guided health flows • OCR-based input for tracking • AI combined with GPS + sensor data ⚙️ Backend & Integrations • Node.js / Python (FastAPI) • Firebase & Supabase (real-time sync) • APIs, push notifications, in-app purchases • GPS + IoT data pipelines 📊 Impact • Fixed unstable wellness apps with sync issues • Built GPS-based fitness features with high retention • Delivered health MVPs without rewrites • Improved BLE reliability and reconnection stability • Integrated AI to reduce user friction, not add complexity 💬 How I Work Clients usually reach out when: • Apps break under real usage • GPS or BLE features are unreliable • MVPs need to become production-ready systems • AI needs to be integrated properly I’ll always point out what’s unnecessary early and clearly. 🏆 Additional Services 6 months free maintenance after launch Full IP transfer from day one (client GitHub) Agile development with regular updates App Store & Play Store deployment handled end-to-end I also work with no-code/low-code tools when it makes sense: Bubble, FlutterFlow, Webflow, Lovable, Base44 + AI APIs (Claude, GPT, OpenAI) 🧩 Core Skills Mobile App Development | iOS | Android | React Native | Flutter | Swift | Kotlin | AI Apps | Healthcare Apps | Fitness Apps | GPS Tracking Apps | Location-Based Services | Geofencing | Real-Time Tracking | BLE Development | IoT Integration | AWS IoT Core | Firebase | Supabase | WebRTC | API Integration | HIPAA-aware systems | In-App Purchases | App Store Deployment 🤝 Why Work With Me Healthcare, Fitness, Wellness, GPS, and connected systems aren’t just features. They need trust, stability, and real-world reliability. That’s what I focus on. 📧 Send me your project idea and I’ll give you a clear, practical next step. Rudy Pasillas