Mozilla Firefox (Source Code Build, C++, C, JavaScript, CSS, HTML, RUST), Mozilla Thunderbird (Source code build, C++, JavaScript, CSS, HTML, Rust), Thunderbird Plug-ins (new feature development, bug fixes, XUL, JavaScript, CSS, JSON, EWS, XML), interface for testing Exchange Server Functionality (Java script, XML, HTML, CSS), development of an e-mail-client application (Java script, JQuery, HTML, CSS, Soap web service for EWS, Rest API, Python), development of Achievo Exchange Sync (Mozilla and Chrome web extensions APIs, JQuery, Java script, JSON, HTML, CSS), migration Thunderbird version 68 to version 78, web server certificate via Acme2 (C, C++, Java, boulder: Go), OsTicket (PHP, MySQL, HTML, JavaScript, CSS), integration methodologies to integrate RIS (Radiology Information System),  LIS (Laboratory Information System) with existing HMS application, GitHub, development of software verification plans and quality assurance procedures, clearly and regularly communicated with management and technical support colleagues, documented and demonstrated solutions by developing documentation flowcharts, layouts, diagrams, charts, code comments and clear code. CI/CD,  Docker and Jenkins, Maven.