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Hey Guys! I’m an Android Developer Kotlin dedicated to helping startups and businesses build high-performance mobile applications. Interested? Drop me a message, and I’ll show you my workflow and how I can help your project thrive! What Android Developer Kotlin Do: ⚪️ Android Kotlin Development: Creating native apps for Android using Kotlin and Java modern UI. ⚪️ App Performance: Optimization, bug fixing Android App , and improving Mobile Develop stability. ⚪️ API Integration: Working with Full Stack teams, REST APIs, and real-time features. ⚪️ App Support: Feature updates for iOS and Android, refactoring, and long-term maintenance. I build Android apps that are not just functional but ready for production. Whether you need a native Android Developer to build from scratch or a Kotlin Developer to scale your current Android App product, I ensure the code is clean and predictable. While I focus on the Android Developer Kotlin Java ecosystem, I understand the importance of cross-platform alignment with iOS, Swift, and Flutter. What I Specialize In Android App Development ✔️ Kotlin Developer expertise: Native development for Android apps. ✔️ Android Developer Kotlin Java standards: Clean Architecture, MVVM, modular structure ✔️ Jetpack components (ViewModel, LiveData, Navigation) and Android Screen Reader support. ✔️ Coroutines and background processing for Mobile Developer projects. ✔️ Room database, SQLite, and local storage. Backend & Integrations ✔️ REST API integration and data handling with Spring Boot or JSP Developer backends. ✔️ Firebase (Auth, Firestore, Push Notifications) and Marketing Cloud Developer tools. ✔️ Salesforce Marketing Cloud Developer triggers and external SDKs. ✔️ WebSockets and real-time updates for Mobile Develop solutions. UI & UX ✔️ Modern UI with XML and Jetpack Compose for any Android Developer India or global project. ✔️ Responsive layouts that match the quality of an iOS Developer or Swift specialist. ✔️ Material Design implementation for iOS Android hybrid feel when needed. ✔️ Perfect user flows, even for complex systems like Magento integrations. Testing & Stability ✔️ Debugging and performance optimization across Bulgaria and international markets. ✔️ Memory optimization and Full Stack Developer level code cleanup. ✔️ Transitioning legacy code from Java Developer to modern Kotlin. ✔️ Web Developer collaboration for seamless API handshakes. Tech Stack: ✔️ Languages: Kotlin, Java, Javascript Developer (API-side), Python Developer (Backend-side). ✔️ Platforms: Android, iOS, Flutter, React Native. ✔️ Architecture: MVVM, Clean Architecture, Full Stack. ✔️ UI: XML, Jetpack Compose, Flutter Developer insights, iOS Developer UI standards. ✔️ Database: Room, SQLite, Java Developer legacy support. ✔️ Other: Google Maps API, Payments, IOS integrations, Bulgaria localized services. Android Developer Kotlin focus on delivering Android App working apps with clear logic, stable performance, and code that is easy to maintain. Whether you are looking for a Mobile Developer or a dedicated Android Screen Reader accessibility expert, I've got you covered. Have a project in mind? Click “Invite”, share what you’re building, and I’ll let you know how I can help.

I'm a Java/Spring Boot backend developer with 6 years of experience across CRM, loyalty, and B2B enterprise platforms — the kind of engineer companies bring in when they need someone who can own a backend end-to-end, not just close tickets. ▪️Performance & scale: On a CRM platform for a solar-installation company, I rebuilt the MongoDB query and indexing strategy and cut execution times by 10x or more across reporting, analytics, and core workflows. ▪️Integrations & automation: I've implemented OAuth2 single sign-on so partner dashboards open with one click from inside a CRM, synced schedules via the Google Calendar API, and set up Apache Kafka producers/consumers to move CRM events into async workflows. I've also built a scheduled pipeline that pulls, deduplicates, and standardizes data from a public research API, with no manual cleanup required. ▪️Ownership & delivery: I led an AI-powered CRM analytics feature from concept to production, including the GitHub Actions CI/CD pipeline that deploys it — end to end, without handing off to another specialist. ▪️Legacy & modernization: I'm comfortable in codebases I didn't write. I converted an aging JSP-based Java server into a proper JSON REST API for mobile compatibility. ▪️I spent 19 months adding features to an inherited application (Sweet Home 3D) without breaking what already worked. ▪️I also built resilient HTTP clients in Node.js (proxy rotation, rate limiting, retry logic) when a project calls for it. ✅ Skill: Backend: Java (8/11/17/21), Spring Boot, Spring Data JPA, Spring Security, Hibernate, Apache Kafka Principles: OOP, SOLID, TDD, GOF Design Patterns; Frontend: CSS/HTML, JavaScript/TypeScript; Databases: SQL (PostgreSQL, MySQL), MongoDB; APIs: REST, JSON/XML, Swagger/OpenAPI; Testing: JUnit, Mockito, TestContainers; DevOps: Docker, Maven, Git, GitHub Actions; Top Rated on Upwork, $10K+ earned across 23 contracts and 619 hours, tagged "Clear Communicator" by 4 separate clients. Please tell me what you're building or what's broken, and I'll tell you honestly what it'll take to fix or ship it.

I am a seasoned software developer with over 10 years of experience specializing in Backend and Full-Stack development. I pride myself on my excellent problem-solving skills and have a strong passion for writing clean and testable code. Clear communication is one of my strengths, making me a valuable team member in any software development project. Preferred Tech Stack: Backend: Java, Spring Boot, Thymeleaf, REST API, PostgreSQL, AWS, Linux, Tomcat, Nginx Frontend (Web): HTML, CSS, Sass, Javascript Frontend (Mobile): Flutter, Dart Cross-Platform: Flutter, Dart I am also proficient in the following technologies: Languages: Java, Scala, Groovy, Kotlin, Golang, JavaScript, TypeScript, Python, Dart, SQL Databases: PostgreSQL, MySQL, Oracle, Cassandra, MongoDB, SQLite, Neo4j Frameworks (Backend): Spring Boot, Spring Security, OpenAPI, Kafka, Zookeeper, Grails Frameworks (Frontend): Angular, React, Flutter, jQuery, Bootstrap Security: Spring Security, OAuth, JWT Technologies: HTML, CSS, JSON, XML, REST API API: REST API, OpenAPI, Swagger Messaging: Kafka, ActiveMQ, RabbitMQ Search: ElasticSearch, Lucene, Kibana Logging: ElasticSearch, Logstash, Kibana Cloud Providers: AWS, Google Cloud Testing: JUnit, Mockito, TestNG, Selenium, Cucumber, Katalon Studio Development Tools: Intellij IDEA, VSCode, Android Studio

I specialize in developing Java web applications using Spring framework. From RESTful Web services to narrowly specialized apps for text recognition and other enterprise tasks. Both front-end and back-end. Also, I can design a relational database using any system you want. Skills: - Java - Spring Framework - Spring Boot - Keycloak - Vert.x - Quarkus - Vue.js - Vaadin Framework - JAX-RS - Hibernate - JSP - Freemarker - Thymeleaf - HTML/CSS - JavaScript - jQuery - Bootstrap - Tesseract OCR, Nicomsoft OCR - MySQL, PostgreSQL, Informix IBM SQL, SQLite - ElasticSearch - MongoDB I have a master degree in Software Engineering from Kyiv Polytechnic Institute. As a developer, I have also taken part and won large number of hackathons.

I help identify critical bugs, broken workflows, and data inconsistencies before they impact users. My focus is practical QA not just checking features, but validating real user flows, business logic, integrations, and overall product stability. I work with web and mobile applications, SaaS platforms, dashboards, ecommerce systems, AI-powered products, and data-driven applications. What you can expect from me ✔ Clear, structured bug reports with reproduction steps, expected vs actual results, screenshots, and impact assessment ✔ Manual testing: Functional, Regression, Smoke, Sanity, Exploratory, User Acceptance, and End-to-End testing ✔ Strong edge-case and negative scenario coverage based on real user behavior ✔ API testing with Postman, including request validation, response verification, error handling, and workflow testing ✔ UI, API, and database validation to ensure consistency across systems ✔ Automation support with Playwright, Cypress, and Selenium ✔ Cross-browser and cross-device testing (Desktop, iOS, Android) ✔ DevTools usage for Network, Console, and request inspection ✔ Test case creation, test execution, bug tracking, and release validation ✔ Clear communication with developers, project managers, and stakeholders How I test I approach products the way real users interact with them: repeated actions, interrupted workflows, invalid inputs, mobile responsiveness, permissions, account states, and unexpected behavior. In addition to standard test execution, I use exploratory testing to uncover hidden issues, inconsistent states, failed requests, usability problems, and workflow gaps that may not be covered by predefined test cases. Tools & Technologies • Postman • Playwright • Cypress • Selenium • Browser DevTools • REST APIs • JSON / XML • SQL (basic querying and validation) • GitHub Actions • Jenkins My goal My goal is simple: help teams release reliable, stable, and user-friendly products by providing thorough testing, actionable feedback, and high-quality bug reports. Available for both short-term projects and long-term collaboration.

📣 Hello, and welcome! I'm a Senior Software developer with 6 years of commercial experience in Java, Springboot, React, Next.js, React Native, Node.js, Nest.js, and Express.js. I'm oriented on results, motivated, and responsible developer with good analytical skills and attention to detail. I'm well-versed in software development, data structures, algorithms, and object-oriented design principles. I'm skilled in utilizing various tools and technologies. Quick learner. Also, I am an active team player who wants to deliver high-quality work and continue expanding my knowledge and skills in software development. I would be happy to work with E-commerce, Fintech, HealthTech, Blockchain, EdTech, PropTech, CRM, TravelTech, InsurTech, LogistecsTech, and Gambling projects. 📌WHAT I'M OFFER: 💻WEB DEVELOPMENT I'm delivering high-performance, responsive web applications. I specialize in building modern front-end interfaces using React.js and Next.js while handling robust backend systems with Node.js, Express.js, and Nest.js. Full-stack capabilities allow me to craft seamless, end-to-end solutions, from user interfaces to database management. 💻 API DEVELOPMENT & INTEGRATION Design and develop custom RESTful APIs and GraphQL endpoints to connect applications. I integrate third-party services like Stripe, Twilio, Google Maps API, and more, ensuring seamless communication between platforms. I also implement secure authentication and authorization systems using JWT, OAuth, or custom protocols. 💻 ENTERPRISE SOLUTIONS (JAVA) I'm building scalable enterprise applications with Spring Boot or lightweight FastAPI solutions for startups. Develop and deploy microservices architectures, automate workflows, and integrate powerful tools like Kafka and RabbitMQ for real-time processing. 💻 REAL-TIME & eCommerce SOLUTIONS I'm developing real-time applications such as chat apps, live notifications, and streaming platforms using WebSockets. Build custom eCommerce platforms with payment integrations like Stripe, PayPal, and others, providing features like cart management, inventory tracking, and order processing. 💻 CLOUD & DevOps I'm deploying and managing scalable applications on cloud platforms like AWS, Google Cloud, Azure, Heroku, and Vercel. I handle CI/CD pipelines for automated testing and deployment, leveraging Docker and Kubernetes for containerized environments. 💻 DATA-DRIVEN APPLICATIONS I'm creating interactive data dashboards using React tools. I automate data pipelines and web scraping tasks with pandas, NumPy, Scrapy, and Selenium. I also integrate machine learning models into applications for advanced analytics and predictions. 📌 My Javascript Front-end skills: Javascript, Typescript, React.js, Next.js, React Native (CLI/Expo), TailwindCSS, Material UI, Ant Design, SCSS, HTML5, CSS3, Redux Thunk, Redux Saga, Chakra UI, Bootstrap. 📌 My Javascript Back-end skills: Node.js, Nest.js, Express.js, Jest, Fastify, GraphQL, Docker. 📌 My Java skills: Java21, Spring (Boot, Core, MVC, Security, Data, Cloud, Javamail), Concurrency, SOLID, OOP, JakartaEE, JSP, Tomcat, Thymeleaf, JUnit, Mockito, Maven, Gradle. Docker, Lombok 📌 My Database skills: Hibernate, JDBC, Liquibase, SQL, NoSQL, PostgreSQL, MySQL, Objection, Knex, Prisma, MongoDB. 📌Other skills: Stripe, Firebase, Mapbox, GoogleMap, Google Analytics, Google Cloud, KuCoin API, OAuth2, WordPress, AWS. 📌API Tools: Swagger, Postman 📌KEYWORDS: JavaScript, Firebase, Vue.js, Angular, Svelte, D3.js, Chart.js, Three.js, PostgreSQL, React.js, Python, Spring Boot, Docker, Redis, Google Analytics, Kubernetes, Next.js, NumPy, Tailwind CSS, Google Maps API, TensorFlow, AWS S3, JPA, Redux, Material-UI, Selenium, MongoDB, Django, Stripe, Node.js, Jupyter Notebooks, OpenCV, Vercel, Cloudflare, React Native, Celery, ElasticSearch, Hibernate, Express.js, PyTorch, Twilio, Nest.js, pandas, RabbitMQ, Spring Framework, Pipedrive, Google Cloud, GraphQL, scikit-learn, MUI, Azure Functions, Jenkins, Ansible, RESTful APIs, Heroku, Kafka, JSP, OpenAPI, FastAPI, Bitbucket, Gradle, Tomcat, SendGrid, Chakra UI, WebSockets, Java EE, Apache Spark, Servlets, Storybook, Maven, JUnit, SQLite, Scrapy, SQLAlchemy, Apache Kafka, PayPal, Azure DevOps, Microservices, Terraform, Electron.js, Webpack, Babel, ESLint, Vite, Jest, Cypress, Puppeteer, Mocha, Jasmine, Lodash, RxJS, Immutable.js.