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I am an experienced Linux administrator. I have 15+ years of experience in Linux system administration and problem-solving. I can troubleshooting all kinds of linux issues, centos migration, centos/ubuntu crash rescue, investigate server performance issue and web server administration. Skills & Deliverables: Cloud Infrastructure & Dedicated VPS Setup (AWS, DigitalOcean, Hetzner, Contabo, Linode etc) Building secure, high-performance servers with proper backup, and automation. Linux Administration(Centos, Ubuntu, Debian, Rocky Linux, Almalinux) Performance optimization, monitoring, troubleshooting, log analysis, and uptime management. Server migration(Centos, Ubuntu, Debian, Rocky Linux, Almalinux) Secure migration of data and app between different servers. Web Server Trouble-shooting Slow server, website troubleshooting and optimization Recurring downtime issue troubleshooting and fix. Centos7 server migration Upgrade centos7 to almalinux 8 or 9. Migrate data&apps from centos7 to Ubuntu/Debian/Rocky/Almalinux Server Upgrade(Centos, Ubuntu, Debian, Rocky Linux, Almalinux) Upgrade ubuntu 14 16 18 20 22 to the latest version. Upgrade Debian , Rocky Linux, Almalinux to the latest version Server rescue(Centos, Ubuntu, Debian, Rocky Linux, Almalinux) Fix linux system crash, file system corruption. Security & Compliance Firewall configuration, access control, TLS/SSL, patching, vulnerability prevention. Backup & Disaster Recovery Strategy Automated backups, retention policies, restore testing, failover planning. Application Hosting & Migration WordPress, Prestashop, Forum app, Node.js, Python apps — smooth migration without downtime. Email Infrastructure & Deliverability Improvement Domain authentication setup (SPF / DKIM / DMARC), inbox placement, fixing spam issues. Why choose me? - Strong skills and extensive experience , can work independently and efficiently , able to fix complex issues - Fast and clear communication, detail and solution oriented - Honest and proactive work ethic

🧪 Senior QA/SQA Engineer | 10+ Years in Manual & Automation Testing 📱 Platforms: Web, Mobile (iOS/Android), Desktop & Mobile Hardware ⚙️ Expertise: Functional, Regression, API, Performance, E2E, Google Play Closed Testing, A/B Testing 🎯 Track Record: 200+ Projects Completed | 30,000+ QA Hours | Product & Web QA Specialist ***************** I help software teams ship faster with fewer bugs through the right mix of automation efficiency, manual testing precision, and AI‑driven testing strategies. With 10+ years in software quality engineering, I have deep expertise across automated, manual, and AI‑augmented testing. I have built automation frameworks from scratch for companies ranging from startups to enterprise, while maintaining strong hands-on manual testing practices for critical user flows and edge cases that automation cannot catch. I also leverage AI tools and LLMs to accelerate test generation, self‑heal flaky tests, and uncover hidden defect patterns. ***************** ✅ WHAT I DELIVER 🏗️ Custom Automation Frameworks — UI (Selenium/Playwright/Appium), API, and white-box testing tailored to your stack 🔍 Strategic Manual Testing — Exploratory testing, user scenario validation, and edge case discovery where human judgment matters most 🤖 AI‑Powered Testing — Intelligent test generation, self‑healing scripts, visual validation with AI, and LLM integration to expand coverage while slashing maintenance 🌐 Website & SaaS Testing — End-to-end validation, cross-browser compatibility, responsive design, user journey testing, and subscription/payment flow verification 🚀 CI/CD Quality Gates — Jenkins/GitHub Actions pipelines that catch defects before they reach production ***************** 📊 RECENT RESULTS ✅ 50%+ reduction in regression testing time through framework optimization ✅ 30% increase in early defect detection via shift-left practices ✅ 40% less test maintenance using AI‑assisted self‑healing and smart locators ✅ Agile transformation leader — guided 5-person QA teams, reducing release cycle from 2 weeks → 3 days ✅ SaaS platform reliability — delivered comprehensive testing ensuring robust subscription flows and multi-tenant data isolation ***************** 🛠️ TECH STACK Java/Kotlin/Python | Selenium/Playwright/Appium/REST Assured | Jenkins/GitHub Actions | Docker | AWS/Azure/GCP | SQL for data validation | LLMs / OpenAI / AI testing assistants ***************** 🎯 DOMAIN EXPERIENCE ✅ Website Testing — Cross-browser (Chrome/Firefox/Safari/Edge) | Responsive design | Accessibility (WCAG) | Performance optimization ✅ SaaS Platforms — Multi-tenant architecture | Subscription/payment flows | Role-based access control | API integration testing | Data security validation ✅ Mobile (Android/iOS) | Web apps | Desktop (Linux/Mac/Windows) | Database migration validation | Hardware-integrated systems ***************** 📬 LET'S CONNECT Available for: Test strategy consulting • Framework architecture • CI/CD setup • SaaS platform testing • Team training • Ongoing QA leadership • AI testing adoption & tooling 👉 Invite me to discuss your quality bottlenecks

Thank you for taking the time to view my profile. I'm a professional electrical engineer with experience in power electronics, digital circuits, analog circuits, and HF RF circuits. My favorite EDA tools are OrCAD or KiCad for schematics capture, Allegro or KiCad for PCB layout, LTspice for analog circuit simulation, Verilog/SystemVerilog/Vivado/ModelSim/Questa for digital and FPGA design, SIMetrix/SIMPLIS for SMPS design, dsPIC33/MPLAB/PowerSmart for digital power design. Still, I have used many other EDA tools under customer/client requests in the past, such as Pspice, TINA-TI, ADS, Quartus Prime, etc. I'm also a professional programmer with experience in PC BIOS, BSP, Linux, and Android, and I'm familiar with many programming languages such as x86 assembly, ARM assembly, C, C++, Java, Python, HTML, CSS, XML, SQL, JavaScript, Unix shell script. I have many mass production designs for domestic clients and some from foreign countries. If you want reference to some of my product designs, I can ask for the client's permission as they are mostly NDA secured. I'm serious about the intellectual properties of others. But you can view my portfolio for a LF N2PK VNA and a Red Pitaya STEMlab125 designs, both are the few best in class amateur measurement equipment with professional device quality, I improved on their original design to better fit my daily electrical test requirements, and as I just produce my own improved design for my private use, so it's legal for me to show them here without IP issues with the copyright holders. My current interest and most recent skills are FPGA, SMPS, digital power, motor control, and automotive electronics.

• Solid background and advanced knowledge in software development, including Java, C++, Javascript, Python, and Unix Shell. • Skilled in working with database management tools such as MySQL, Postgresql, MongoDB, Redis, and Cassandra. • Skilled in massive data processing, including Hadoop, Spark, Kafka, RabbitMQ. • Skilled in dockerization and container orchestration, work in Devops. • Highly organized with exceptional commitment to task completion and quality assurance when working with computer software programs. • Good leadership skills, over 3 years of experience on scrum master position. • Major work in telecom radio network system, telecom cloud, Devops, IoT and Block Chain.

I am a seasoned IT System Engineer with a broad coding background and a proven track record in setup systems and softwares, designing and managing robust infrastructure. My core expertise lies in: ✅Systems & Virtualization: Deep proficiency in Linux, server hardware, and virtualization technologies. ✅DevOps & Cloud Practices: Skilled in implementing DevOps principles, with experience in networking, DNS, and storage (RAID) solutions. ✅Embedded & IoT: Hands-on experience in embedded systems and IoT projects, from prototyping and soldering circuit boards to coding. My tech stack： • C, CPP, MIPS Assembly, QEMU and TCG Dev, Linux distro porting • RHEL/CentOS/RockyLinux, Debian/Ubuntu, LoongArch Linux • Apache, Nginx, MySQL/MariaDB, PHP, PHP-FPM, CA and SSL • Python, Java, Objective C and iOS • VMware vSphere, pfSense/OPNSense, OpenWRT, Prometheus, Cockpit • Gitlab, Apache Subversion, Redmine, Jenkins, Docker • NextCloud, ownCloud A Comprehensive Technical Ecosystem: My experience is unified by a deep commitment to Free and Open-Source software. This spans the entire stack: from porting systems for IC design to operating GNU/Linux clusters; from server-side coding to mobile development; and from troubleshooting complex networks and RAID to implementing open-source alternatives to proprietary suites like Google Worksapce and Microsoft 365. End-to-End Solution Delivery: I leverage this broad skill set to deliver complete solutions—whether it's applying foundational knowledge (like that of Internet root servers) to configure complex DNS for a new business site, or developing strategies to enhance efficiency by migrating to public clouds or building cost-effective private clouds. Beyond technical know-how, I am driven by a passion for understanding the "why" behind systems. I am a meticulous professional who prioritizes client success through proactive communication and a detail-oriented approach. With an A-to-Z understanding of computers and networks, complemented by management experience, I am poised to deliver reliable and efficient service.

Hello, my English name is Change Law(while Qunzhi Luo is the Pinyin of my Chinese name, which is on my national ID). I have more than 7 years of experience in system/hardware/database admin, about 3 years of programming(C++ and python). 2016.03 IBM Certified System Administrator AIX V1 2007.10 Oracle Certified PL/SQL Developer Associate 2007.05 Advanced Programmer Certification 2006.05 College English Test-6 with 552 degrees out of 750