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Are you looking to build a high-performance SaaS platform, automate a complex supply chain, or integrate secure, production-ready AI into your business workflow? Many developers can write code, but very few understand how to seamlessly blend cutting-edge AI/ML systems with scalable, enterprise-grade architecture while ensuring strict data security (HIPAA, PCI-DSS). I am a Full-Stack Developer and AI/ML Engineer with extensive experience architecting end-to-end solutions for SaaS, Supply Chain, Healthcare (HIS/HMS), and custom ERP systems. Whether you need to build an MVP from scratch or scale an existing enterprise platform, I deliver clean, maintainable code and robust infrastructure. 🚀 Core Expertise & How I Can Help You: AI/ML & GenAI Integration: Building intelligent RAG systems, custom chatbots, and LLM-powered workflows using OpenAI, Anthropic, LangChain, and Vector Databases (Pinecone, Qdrant). Robust Backend & Architecture: Designing secure, high-throughput microservices and APIs using Node.js (NestJS), Python (FastAPI/Django), and PHP, backed by PostgreSQL, MongoDB, or Redis. Modern, Responsive Frontends: Crafting seamless web and mobile interfaces using React, Next.js, Angular, Vue.js, and React Native. Cloud, DevOps & Compliance: Deploying production-ready applications on AWS/GCP/Docker with CI/CD pipelines, keeping security and regulatory standards (HIPAA, GDPR) at the forefront. 🛠️ Technical Snapshot: Frontend: React, Next.js, Angular, Vue.js, React Native, Tailwind CSS Backend: Node.js (NestJS/Express), Python (FastAPI/Django), PHP, Java AI/ML: LLMs, LangChain, Vector DBs, Prompt Engineering, RAG Systems Cloud & Databases: AWS, GCP, Docker, Kubernetes, PostgreSQL, MySQL, MongoDB, Redis Let’s build something scalable. Click the "Invite to Job" or "Hire" button on the top right, and let’s discuss how we can bring your project to life.

✔ 𝗜 𝗵𝗲𝗹𝗽 𝘀𝗺𝗮𝗹𝗹 𝗯𝘂𝘀𝗶𝗻𝗲𝘀𝘀𝗲𝘀 𝗽𝗿𝗲𝘃𝗲𝗻𝘁 𝗰𝗼𝘀𝘁𝗹𝘆 𝗽𝗿𝗼𝗱𝘂𝗰𝘁𝗶𝗼𝗻 𝗶𝘀𝘀𝘂𝗲𝘀 𝗮𝗻𝗱 𝗶𝗻𝗰𝗿𝗲𝗮𝘀𝗲 𝗿𝗲𝘃𝗲𝗻𝘂𝗲 𝘁𝗵𝗿𝗼𝘂𝗴𝗵 𝘀𝘁𝗿𝗮𝘁𝗲𝗴𝗶𝗰 𝗤𝗔 𝗮𝗻𝗱 𝘂𝘀𝗲𝗿-𝗳𝗼𝗰𝘂𝘀𝗲𝗱 𝘁𝗲𝘀𝘁𝗶𝗻𝗴. 🏆 𝟐𝟎𝟎 + web sites and 📱 𝟔𝟎+ mobile apps were tested, improved and debugged, ensuring the best quality, usability and conversion. 𝟏𝟎+ 𝐲𝐞𝐚𝐫𝐬 𝐨𝐟 𝐞𝐱𝐩𝐞𝐫𝐢𝐞𝐧𝐜𝐞, 𝟔𝟖𝟎𝟎 hours worked at Upwork. Experience in testing AI-driven apps. ▶ Senior Software Tester / QA Expert / Web, Mobile & AI app manual testing / QA Analyst / Project Manager I work with small business: WordPress / WooCommerce, Shopify web development companies, early-stage SaaS startups, product owners and indie software developers. Your digital business's success is based on the quality of your software! My top priority is identifying issues before they reach your users. My specializations: • AI - Extended Manual QA: Mobile App Testing - iOS / Android, Web testing • Technical Project Management 𝐖𝐡𝐲 𝐝𝐨 𝐜𝐥𝐢𝐞𝐧𝐭𝐬 𝐜𝐡𝐨𝐨𝐬𝐞 𝐭𝐨 𝐰𝐨𝐫𝐤 𝐰𝐢𝐭𝐡 𝐦𝐞? 👇 ✔"Vitaly is an amazing tester and gives such much attention to detail. He has given me new tools to use in my own business and has streamlined a lot of things for me. Could not recommend him more." As a results-driven QA Engineer, I deliver high-quality, reliable, and user-friendly products that exceed expectations. By leveraging a wide range of QA tools, devices, and testing methodologies, I ensure top-notch results that drive customer satisfaction. 🔍 𝑪𝒐𝒓𝒆 𝑴𝒂𝒏𝒖𝒂𝒍 𝑸𝑨 𝑻𝒆𝒔𝒕𝒊𝒏𝒈 𝑺𝒆𝒓𝒗𝒊𝒄𝒆𝒔: ✅ Risk-Based Testing ✅ AI-Extended QA ✅ Conversion focused e-Commerce QA ✅ Websites, Mobile App, Flutter, Game Testing ✅ Functional Testing ✅ Cross Browser / Cross Device Testing ✅ End-to-End Testing ✅ Compatibility Testing, Responsive Design Testing ✅ UI/UX Testing and Review ✅ Exploratory Testing, Black Box Testing ✅ Usability Testing, User Acceptance Testing (UAT) ✅ Smoke, Sanity, Regression Testing ✅ Beta Testing, Pre-Launch, Post-Release QA ✅ Test Case Design & Execution ✅ Agile Scrum ✅ QA Management ◉ Domains tested: AI - powered apps, Healthcare (4 years experience - QA Lead), WordPress, WooCommerce, E-commerce, Shopify, Laravel, OpenCart, Magento, Real Estate, Wellness solutions, Kids and EdTech applications, CRMs, dating apps, Bubble io (no-code apps), custom websites, iGaming / Betting, Online casinos and games 🧪 𝑻𝒐𝒐𝒍𝒔, 𝑬𝒏𝒗𝒊𝒓𝒐𝒏𝒎𝒆𝒏𝒕𝒔 & 𝑫𝒆𝒍𝒊𝒗𝒆𝒓𝒂𝒃𝒍𝒆𝒔: • I combine the best QA techniques & AI to increase testing efficiency and covering • Mobile App Testing: Android Studio, TestFlight, Diawi, iMazing & Emulators, Postman • Bug Tracking & PM tools Jira, Trello, Asana, Monday com, Notion, GitHub I supply Detailed Bug Reports with Annotated Screenshots, Videos • Cross-device Testing: Browser Stack, Blisk, DevTools / Сonsole • Understanding frontend - HTML, CSS, JS • Familiar with on-page SEO Experience in QA Documentation - Design and UI testing: Photoshop, Figma, Adobe XD, PerfectPixel • Conversion: Hotjar - Project Management Support 🤝 𝐖𝐡𝐲 𝐖𝐨𝐫𝐤 𝐖𝐢𝐭𝐡 𝐌𝐞? As a Expert Software QA and Project Manager, I bring a unique blend of technical expertise and business awareness to every project. With a proven track record in WordPress web development and QA, I deliver high-impact solutions that drive results. By combining technical expertise with collaborative approach, I help my clients to launch reliable, user-friendly products that are over the top. My experience in the IT field is also underscored by the fact that I run my own WordPress / WooCommerce dev and QA company. Soft skills: ◉ Adaptable & Results-Oriented: I'm a quick learner who delivers results-driven solutions. I prioritize quality over everything else. ◉ Industry Expertise: I stay current with the latest industry trends, test design methodologies, and best practices in QA software testing. ◉ Dedicated Client Support: I'm always available for open communication, ensuring your needs are met and concerns are addressed. ✅ I can successfully meet deadlines. I'm available for both short-term QA tasks and long-term collaboration. 💬 There are few verified reviews from my happy Customers: ✔I can recommend Vitaly's website QA testing services enough. Their professionalism, speed, and meticulous attention to detail are second to none. If you are seeking top-notch QA services, Vitaly is the team to trust. I am truly grateful for their exceptional work and will undoubtedly engage their services for any future QA needs. ✔Vitaly paid great attention to details. I would recommend him on QA tester /Senior QA role. Well done!; ✔Excellent knowledge and experience about testing 📩 Let’s work together to ensure your product is fully tested and ready for success! Feel free to drop me a message on Upwork - just click the button in the top-right corner. 𝑩𝒆𝒔𝒕 𝑹𝒆𝒈𝒂𝒓𝒅𝒔, 𝑽𝒊𝒕𝒂𝒍𝒚 𝑩𝒊𝒆𝒍𝒊𝒂𝒌𝒐𝒗

Hello! I’m Dalton Cabrera, a Full Stack Software Developer with over 8 years of experience. I work on web, desktop, and mobile projects, helping businesses create useful software. My Skills: Full-Stack Development: I can handle both frontend (Vue.js, AngularJS, Bootstrap) and backend (ASP.NET Core, Laravel, Web API), plus mobile apps with Flutter. Technical Knowledge: Backend: C# / .NET, ASP.NET Core, Laravel, PHP, REST APIs, Entity Framework, Node.js Frontend: Vue.js / Vue 3, React, JavaScript, TypeScript, HTML5, CSS3, Tailwind CSS Mobile: Flutter, Cross-Platform Mobile Development, iOS & Android Development Databases: PostgreSQL, MySQL / MariaDB, SQL Server, SQLite Cloud & DevOps: Azure, Docker, Linux / Ubuntu, Nginx, Redis, CI/CD, GitHub / GitLab Integrations: Stripe API, Microsoft Graph, Gmail API, Google Maps API, OpenAI API, REST API Integrations, Webhooks, SMTP / Email integrations Architecture: Full-Stack Development, SaaS Development, Multi-Tenant Architecture, API-First Architecture, RBAC / Permissions, Background Jobs & Queues Reliable: I always meet deadlines and communicate clearly to ensure your project is a success. Why Work With Me? I am easy to work with and understand what clients need. I can help you with a custom web app, a mobile app, or improving your current system. I aim to meet and exceed your expectations. Let’s talk about your project. I’m excited to work together and achieve great results. Best regards, Dalton Cabrera

🏆 𝗖𝘂𝘀𝘁𝗼𝗺 𝗦𝗼𝗳𝘁𝘄𝗮𝗿𝗲 & 𝗔𝗜 𝗘𝗻𝗴𝗶𝗻𝗲𝗲𝗿 | 𝗪𝗲𝗯, 𝗠𝗼𝗯𝗶𝗹𝗲 & 𝗦𝗮𝗮𝗦 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 | 𝗙𝗼𝘂𝗻𝗱𝗲𝗿 𝗼𝗳 𝗭𝗮𝗸𝗖𝗼𝗱𝗲𝗫 𝗟𝗧𝗗 I'm Zakawat Abbas, Founder & CEO of ZakCodeX LTD, a UK software development company that helps startups, SMEs, and enterprises build custom software, AI-powered applications, SaaS platforms, mobile apps, and scalable web solutions. My team delivers complete software solutions, from product strategy and UI/UX design to development, cloud infrastructure, deployment, and long-term support. We focus on writing clean, scalable code that grows with your business rather than creating quick fixes that need rebuilding later. ⚡ 𝗪𝗲'𝗿𝗲 𝗮 𝗴𝗿𝗲𝗮𝘁 𝗳𝗶𝘁 𝗶𝗳 𝘆𝗼𝘂'𝗿𝗲 𝘁𝗵𝗶𝗻𝗸𝗶𝗻𝗴: ● "I need a reliable software development partner who can own the project from start to finish." ● "I want to build an MVP that can scale into a successful SaaS business." ● "I need AI integrated into my application or business workflow." ● "I need experienced developers for both frontend and backend." ● "I want secure, scalable software built with modern technologies." ● "I need long-term technical support after launch." 💻 𝗖𝘂𝘀𝘁𝗼𝗺 𝗦𝗼𝗳𝘁𝘄𝗮𝗿𝗲 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 Custom business software, SaaS platforms, CRM systems, ERP solutions, internal dashboards, workflow automation, enterprise applications, REST APIs, GraphQL APIs, third-party integrations, and cloud-native software built for long-term scalability. 🌐 𝗪𝗲𝗯 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 High-performance web applications using React.js, Next.js, Node.js, Laravel, Python, FastAPI, and modern cloud infrastructure. We build SEO-friendly, secure, scalable websites and web applications optimized for performance and user experience. 📱 𝗠𝗼𝗯𝗶𝗹𝗲 𝗔𝗽𝗽 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 Cross-platform mobile applications using React Native and Flutter for iOS and Android. We develop consumer apps, enterprise applications, booking platforms, ecommerce apps, healthcare solutions, AI-powered mobile apps, and startup MVPs. 🤖 𝗔𝗜 & 𝗔𝘂𝘁𝗼𝗺𝗮𝘁𝗶𝗼𝗻 Generative AI, OpenAI integration, Claude AI, AI chatbots, business automation, machine learning, natural language processing, computer vision, intelligent workflows, AI assistants, and custom AI-powered business solutions. 🎨 𝗨𝗜/𝗨𝗫 𝗗𝗲𝘀𝗶𝗴𝗻 Modern user interfaces designed in Figma, including UX research, wireframes, prototypes, design systems, and developer-ready UI for web and mobile products. 🛒 𝗘𝗰𝗼𝗺𝗺𝗲𝗿𝗰𝗲 Custom ecommerce platforms, Shopify, WooCommerce, payment gateway integration, inventory management, API integrations, and conversion-focused online stores. 🛠️ 𝗧𝗲𝗰𝗵 𝗦𝘁𝗮𝗰𝗸 ◉ Frontend: React.js, Next.js, TypeScript, JavaScript, Tailwind CSS, HTML5, CSS3 ◉ Backend: Node.js, Express.js, Laravel, Python, Django, FastAPI, PHP ◉ Mobile: React Native, Flutter, Android, iOS ◉ AI: OpenAI API, Claude AI, GPT, Machine Learning, NLP, Computer Vision ◉ Cloud: AWS, Docker, Vercel, DigitalOcean, Firebase ◉ Databases: PostgreSQL, MySQL, MongoDB, Firebase ◉ APIs: REST API, GraphQL, Stripe, PayPal, Third-Party API Integration 🔢 𝗪𝗵𝘆 𝗰𝗹𝗶𝗲𝗻𝘁𝘀 𝗰𝗵𝗼𝗼𝘀𝗲 𝗺𝗲 ✅ Founder & CEO of ZakCodeX LTD, UK software development company ✅ Complete product development from idea to launch ✅ Modern AI-first software development approach ✅ Clean, secure, scalable, production-ready code ✅ Transparent communication and on-time delivery ✅ Long-term technology partner focused on business growth 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝗶𝗲𝘀: • Healthcare • Real Estate • Ecommerce • AI • SaaS • Legal • Education • Travel • Hospitality • FinTech • Logistics • Startups • Enterprise Software 𝗞𝗲𝘆𝘄𝗼𝗿𝗱𝘀: • Custom Software Development • Full-Stack Developer • Web Development • Mobile App Development • AI Development • Generative AI • AI Chatbots • React Developer • Next.js Developer • Node.js Developer • Python Developer • React Native Developer • Flutter Developer • SaaS Development • CRM Development • API Integration • AWS • Shopify Development • UI/UX Design • Ecommerce Development • Business Automation • MVP Development • OpenAI Integration • Claude AI • Machine Learning

🌐🚀 MVP / SAAS Specialist Expertise in | AI Developer | RAG | LLM | AI Integration | Python | OpenAI API Integration | Artificial intelligence | Machine Learning | Langchain | Django React JavaScript | FastAPI | AI agent | AI App Development | AI bot | AI chatbot | AI Agent | Restful API | PostgresSQL | Botpress | PostHog | MCP Server | Multi-Agents/Multiple Agents | Voice AI 🔑 𝐈 𝐛𝐮𝐢𝐥𝐝 𝐚𝐧𝐝 𝐝𝐞𝐩𝐥𝐨𝐲 𝐜𝐮𝐬𝐭𝐨𝐦 𝐰𝐞𝐛 𝐚𝐩𝐩𝐥𝐢𝐜𝐚𝐭𝐢𝐨𝐧𝐬, AI-Powered MVP, AI Healthcare Tools, AI Writing Tool, GPT Clone, Full Stack Application, Multi-Tenant 𝐚𝐧𝐝 𝐢𝐧𝐧𝐨𝐯𝐚𝐭𝐢𝐯𝐞 𝐀𝐈 𝐬𝐲𝐬𝐭𝐞𝐦𝐬 𝐭𝐡𝐚𝐭 𝐬𝐨𝐥𝐯𝐞 𝐜𝐨𝐦𝐩𝐥𝐞𝐱 𝐩𝐫𝐨𝐛𝐥𝐞𝐦𝐬, 𝐜𝐫𝐞𝐚𝐭𝐞 𝐧𝐞𝐰 𝐯𝐚𝐥𝐮𝐞, 𝐚𝐧𝐝 𝐢𝐦𝐩𝐫𝐨𝐯𝐞 𝐮𝐬𝐞𝐫 𝐞𝐱𝐩𝐞𝐫𝐢𝐞𝐧𝐜𝐞𝐬. 🎁 A 100% refund, if I'm unable to meet our agreed commitments. No questions asked! 𝐊𝐞𝐲 𝐅𝐚𝐜𝐭𝐬: 🧑‍💻 8+ years of experience as a Full Stack Developer and Artificial Intelligence Specialist 🚀 50+ market-winning projects launched ⌛ Around 600 hours on Upwork 🎯 Top-Rated on Upwork 🌉𝐈'𝐯𝐞 𝐬𝐨𝐥𝐯𝐞𝐝 𝐞𝐧𝐠𝐢𝐧𝐞𝐞𝐫𝐢𝐧𝐠 𝐩𝐫𝐨𝐛𝐥𝐞𝐦𝐬 𝐟𝐨𝐫 𝐭𝐨𝐩 𝐜𝐨𝐦𝐩𝐚𝐧𝐢𝐞𝐬 𝐚𝐧𝐝 𝐬𝐭𝐚𝐫𝐭𝐮𝐩𝐬 𝐚𝐫𝐨𝐮𝐧𝐝 𝐭𝐡𝐞 𝐠𝐥𝐨𝐛𝐞 ☑️ Under Armour ☑️ Snowflake ☑️ Estateza ☑️ SearchLook ☑️ Sparrowcharts 💡 𝐖𝐡𝐚𝐭 𝐜𝐚𝐧 𝐈 𝐛𝐫𝐢𝐧𝐠 𝐭𝐨 𝐲𝐨𝐮𝐫 𝐭𝐚𝐛𝐥𝐞? ☑️ Full Stack Development for robust and scalable web applications, including both front-end and back-end technologies ☑️ Custom Web and Application Development utilizing frameworks like Python, React, Django, React.js / Angular / Next.js / Nest / Nust / Golang and Node.js ☑️ Expertise in LLMs and ChatGPT integration to enhance application functionalities ☑️ Proficiency in RESTful APIs, GraphQL, and database management ☑️ Experience with cloud services like AWS, Azure, and Google Cloud for deployment and scaling ☑️ Strong problem-solving skills and ability to optimize user experiences and application performance 🌟𝐇𝐞𝐫𝐞'𝐬 𝐰𝐡𝐚𝐭 𝐂𝐥𝐢𝐞𝐧𝐭𝐬 𝐡𝐚𝐯𝐞 𝐭𝐨 𝐬𝐚𝐲 𝐚𝐛𝐨𝐮𝐭 𝐦𝐞: 🌟 Ali Hamza is in the top tier of software developers and data engineers. He is far more than an implementer; he is a strong architect. During this project set, Usama worked on data from major US corporations 🌟 One of the best developers I have ever worked with. He is always on time and does exactly what he says he will do. I could not recommend him enough. 🎯 𝐈 𝐩𝐨𝐬𝐬𝐞𝐬 𝐞𝐱𝐩𝐞𝐫𝐭𝐢𝐬𝐞 𝐢𝐧 𝐭𝐡𝐞 𝐟𝐨𝐥𝐥𝐨𝐰𝐢𝐧𝐠 𝐝𝐨𝐦𝐚𝐢𝐧𝐬 ☑️ Full Stack Development: ☑️ Backend: ☑️ Python ☑️ Django ☑️ Flask ☑️ NodeJs, Express.js ☑️ Rest API, SOAP ☑️ Websocket ☑️ Third party integration ☑️ Frontend: ☑️ Html5, Css3, Bootstrap ☑️ Javascript ☑️ ReactJs, Angular ☑️ VueJs ☑️ NextJs, NuxtJs ☑️ Ajax, JSON, XML, XHTML, SVG, Canvas ☑️ API integration, OpenAI API ☑️ DevOps: ☑️ CI/CD Pipelines ☑️ IaC ☑️ Docker ☑️ Kubernetes / Terraform ☑️ Elasticsearch ☑️ Cloud Computing (Azure, AWS, Google Cloud) ☑️ Version Control (Git, GitHub) ☑️ Containerization + Orchestration (Docker, Kubernetes) ☑️ Spring Boot / Java, Microservices Architecture ☑️ Real-time / Streaming / Event-driven architectures ☑️ Session Recordings / Session Replays ☑️ GraphQL / gRPC ☑️ Kafka / Redpanda (real-time streaming) ☑️ Generative Artificial Intelligence (GenAI) ☑️ Large Language Models (LLMs) ☑️ Natural Language Processing (NLP) ☑️ ChatBots and Virtual Assistants ☑️ Text to Image Modelling ☑️ Vector Databases ☑️ Retrieval-Augmented Generation (RAG) ☑️ ChatGPT ☑️ OpenAI ☑️ AI/ML (Artificial Intelligence + Machine Learning) ☑️ Multimodal AI / NLP ☑️ Agentic AI / Autonomous Agents ☑️ “Vibe Coding” / AI-first / prompt-driven dev workflows ☑️ Explainable AI / Ethical, Sustainable AI ☑️ Edge AI / On-device / Federated Learning ☑️ Web Scraping ☑️ Data Extraction ☑️ Data Scraping ☑️ Scrapy ☑️ Selenium ☑️ Beautiful Soup ☑️ Requests ☑️ Deployment and scheduling the scraping scripts on server ☑️ PostHog / Mixpanel / Amplitude / Segment (Twilio Segment) ☑️ OpenTelemetry (Datadog / Grafana / Sentry ☑️ LaunchDarkly / GrowthBook / VWO / Optimizely / Klaviyo ☑️ Airbyte / Fivetran / DBT ☑️ Auth0 / Clerk / SuperTokens / Google Auth ☑️ Stripe / Paddle ☑️ Plaid AI + Analytics Integrations ☑️ LangSmith / LangFuse – Observability and evaluation layer for LLM apps. ☑️ Weaviate / Pinecone / Qdrant – Vector DBs for AI features with analytics hooks. ☑️ Whylabs / Arize AI – ML observability & monitoring (similar to PostHog but for models). I am a Fullstack AI Developer - Python Django, React, Flask, API Integration I can help you to build: ⚡ Fast MVP Development (AI-Powered) ✅ ⚡ AI Powered SAAS Applications ✅ ⚡ AI Agent RAG Systems | AI Chatbots ✅ ⚡ Open AI API Integrations / LLM ✅ ⚡ Full stack Development (AI/ML, Django, React) ✅ ⚡ AI Workflows Automation ⚡ Voice AI tools Thank you for visiting my profile. Looking forward to working with you! I will 💲REFUND 💲, if your expectation wont meet. For reference, you can see my work and testimonials below. Lets Chat!

I have over 6 years of experience as a Manual QA Tester, working on web and mobile applications for an international client in Germany. My daily work includes functional, regression, exploratory, and usability testing, creating detailed bug reports in Azure DevOps, and collaborating closely with developers to ensure high-quality releases. Beyond finding bugs, I always evaluate whether a feature makes sense from the user's perspective. I enjoy identifying confusing workflows, UX inconsistencies, and opportunities to improve the overall user experience.