Hire the Best Debuggers
in Ukraine

Hi, my name is Arsen. I’m a Senior C++ and Python developer with 5+ years of experience building software for Linux, Windows, and embedded systems. I focus on clean, efficient, and reliable solutions for low level, backend, and performance critical tasks. What I bring to projects: • C/C++ development: STL, Boost, Boost ASIO, Qt, WinAPI, OCCI, V8, POSIX, multithreading • Python development: automation tools, data pipelines, backend logic, Django • Database engineering: Oracle, SQLite, MongoDB, data export tools, batch processing, custom type conversion • Linux systems programming: networking utilities, driver level interaction, Linux kernel headers, OpenWRT, desktop and CLI tools • Wireless and low level networking: Generic Netlink, nl80211, libnl/libmnl, Wi Fi scanning tools, protocol and frame parsing • Reliability and performance: profiling, transactional workflows, data integrity focused design, Dockerized builds, CI/CD with TeamCity • Cross platform delivery: Linux and Windows applications, Make, CMake, Conan, Git/SVN, GDB, Valgrind, Doxygen, Bash I have built tools ranging from high performance Wi Fi scanners in C that interact directly with the Linux wireless stack, to cross platform C++ command line utilities that export Oracle data into SQLite with transactional safety and performance profiling. I am comfortable working close to the system, optimizing throughput, handling large datasets, and designing software that is maintainable and stable in production. Clients usually trust me with complex backend, systems, and infrastructure related tasks where performance, correctness, and long term reliability matter. If you are looking for a developer who can work on C++, Python, Linux internals, networking, or data heavy applications, let’s talk. 🙂

If your system got slower over time and nobody really knows why — that’s usually where I come in. Most developers avoid messy data, slow queries, and systems nobody wants to touch. That’s where I do my best work. My core is .NET and SQL. Not just writing queries, but understanding why things break when data grows, and fixing it without turning everything upside down. What I work with: • C# / .NET — data processing, automation, background services, desktop tools • SQL (deep) — complex queries, performance tuning, execution plans, large datasets • APIs & backend — REST, Node.js, Linux deployments • Automation — Selenium, scraping, data pipelines, legacy integrations • Infrastructure — Docker, Linux, FastAPI, PostgREST, full stack setup • Frontend — AG Grid, WordPress customization I also use AI in real work — tools like Claude and AI agents help me move faster, understand unfamiliar stacks, and scale solutions without slowing down. So if your project runs on something new — that’s not a blocker. I’ve worked with old and undocumented systems too — where you don’t have docs, only behavior. If you already tried the obvious fixes and they didn’t work — that’s usually when I get involved. I don’t need long explanations. I read the system, find the real issue, and fix that. I won’t promise miracles. But I will tell you exactly what’s wrong and what it takes to fix it.

I design, build, and maintain Make and Zapier automation -- CRM integrations, email campaigns, AI-assisted document workflows, and multi-scenario orchestrations for SaaS and marketing teams. How I work: 1. Architect. A business event -- "send a quote", "onboard a client", "close a deal" -- becomes a top-level orchestrator that fans out to focused subscenarios, with Make Data Stores handling shared state and idempotency. I design for production from the start, not for demos. 2. Builder. I work across the full Make module stack: HTTP, webhooks, JSON transforms, Google Workspace, Slack, Jira, Xero, OpenAI, Gemini. When off-the-shelf connectors don't cover a requirement, I build custom Make apps with their own modules, RPCs, IML functions, and webhooks. 3. Debugger. I own scenarios end-to-end. When something breaks, I use Make's execution logs, DLQ, and data stores to reproduce the exact failure, not guess at it. What I build: - Multi-step workflows in Make and Zapier - CRM integrations: HubSpot, ActiveCampaign, Pipedrive, Klaviyo - Email campaign automation and list management - AI assistants and AI bots, on-site or via API - AI-assisted document workflows: generation, parsing, routing - Finance and accounting automation: Xero, ERP-style job management - Lead capture: opt-in forms, landing pages, funnels - Cross-platform data sync with idempotent transfers Tools: Make · Zapier · ActiveCampaign · HubSpot · Klaviyo · Mailchimp · Pipedrive · Xero · ClickUp · Jira · Missive · OpenAI · Gemini · Google Workspace · Slack · ClickFunnels · Vapi What I guarantee: Scope and deadlines defined before work starts. Regular updates at every stage. Everything tested before handoff. Refund if something goes wrong. I find the answer if I don't have it yet.

Expert React Native & Expo mobile app developer with over 8 years of hands-on experience building high-performance, scalable, and user-friendly cross-platform applications for both iOS and Android. I specialize in turning ideas into successful published apps — from MVP development to App Store & Play Store deployment, user acquisition, and post-launch growth using mobile measurement and marketing tools. 𝐓𝐞𝐜𝐡𝐧𝐢𝐜𝐚𝐥 𝐄𝐱𝐩𝐞𝐫𝐭𝐢𝐬𝐞 Core Stack: — React Native (Advanced / Expert level) — Expo (Bare Workflow, Custom Dev Client, EAS Build & Submit) — TypeScript, JavaScript (ES6+) — Redux / Redux Toolkit / Zustand / MobX (State Management) — React Navigation, React Query (TanStack Query), Axios Key Tools & Integrations: — Payments & Subscriptions: Stripe, RevenueCat, Superwall (paywall optimization) — Analytics & Marketing: Appsflyer (MMP), Firebase Analytics, Mixpanel, Amplitude — Backend: Firebase, Supabase, Node.js, AWS Amplify — UI/UX: NativeBase, Tamagui, Styled Components, Reanimated 2/3, Gesture Handler, Lottie — Performance Optimization: Hermes Engine, Flipper, React Native Debugger, Code Splitting, Memoization, Image Optimization, App Size Reduction — Testing: Jest, Detox, React Native Testing Library — CI/CD & Deployment: EAS (Expo Application Services), Fastlane, GitHub Actions Mobile Platform Experience: — Deep knowledge of iOS (Swift bridging when needed) and Android (Kotlin/Java modules when required) — App Store and Google Play publishing, ASO (App Store Optimization), provisioning profiles, code signing, and release management 𝐖𝐡𝐚𝐭 𝐈 𝐃𝐞𝐥𝐢𝐯𝐞𝐫 I don’t just code I help you build market-ready mobile products. My typical project flow includes: — Rapid MVP development (usually 4–8 weeks depending on complexity) — Pixel-perfect, smooth, and native-like UI/UX with excellent performance — Subscription-based apps with optimized paywalls (strong experience with Superwall + Stripe) — Deep integration with Appsflyer for attribution, fraud prevention, and marketing analytics — App performance optimization (60fps animations, fast loading, low battery consumption) — Secure, scalable, and maintainable codebase following best practices — App Store / Play Store submission and rejection handling 𝐖𝐡𝐲 𝐂𝐥𝐢𝐞𝐧𝐭𝐬 𝐂𝐡𝐨𝐨𝐬𝐞 𝐌𝐞 — Fast delivery without compromising code quality — Strong focus on performance & user experience — apps that feel truly native — Clean, well-documented, and scalable code (easy for other developers to continue) — Proactive problem-solver who suggests better technical and product solutions — Excellent English communication and regular updates — Long-term mindset — I treat your app like my own Whether you need a new app from scratch, a redesign, performance optimization, subscription system implementation, or post-launch marketing integration (especially with Appsflyer), I can help you achieve your goals efficiently. I’ve successfully delivered more than 15 mobile applications (most built with React Native + Expo) across various industries including fintech, health & fitness, social, e-commerce, and productivity. 𝐑𝐞𝐚𝐝𝐲 𝐭𝐨 𝐛𝐮𝐢𝐥𝐝 𝐬𝐨𝐦𝐞𝐭𝐡𝐢𝐧𝐠 𝐠𝐫𝐞𝐚𝐭 𝐭𝐨𝐠𝐞𝐭𝐡𝐞𝐫? If you're looking for a reliable, skilled, and results-oriented React Native Expo expert who understands both development and the business side of mobile apps (subscriptions, user acquisition, analytics), feel free to message me. Let’s discuss your project and see how we can work together to bring your idea to life successfully.

My current specialization is the powerful PHP frameworks - CodeIgniter (14+ years exp.) and Laravel (2+ year exp.). I am also heavy experienced in the following areas: HTML, CSS, MySQL, Maria DB, JavaScript, TypeScript, Ajax, JQuery, Bootstrap, Tailwind, Git etc. My past projects were related to full stack or backend developing - creating new website pages, creating and maintaining API, enhancing or boosting SQL queries, bugs fixing, integrating 3rd party plugins/services/APIs (AWS, payment gateways etc.) and so on. I like to learn something new and I don't afraid to use any software that I haven't used before. That's why I already successfully finished many projects with different difficulty levels. So I'll be glad to use my developing experience to please you with great results. Hope for our cooperation.

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