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Experienced (15+ years) developer and friendly Ruby on Rails and React/Next.js/Redux Developer/Mentor (with passion for helping others learn) | ★ 3,590+ 5 ★ sessions/jobs. 8+ years on top of the Codementor Ranking ★ https://www.codementor.io/ruby-on-rails-experts I am a Senior Software Engineer from Toronto, currently working as a Ruby on Rails and React/Redux Developer at theScore Inc. I am passionate about helping and mentoring people, especially those who are new to web development and the programming world. I am specialized in explaining the core concepts of Ruby and Rails, Javascript, React, APIs and everything else along with the best practices. I focus on the learning experience of my students and make sure they get exactly what they want. I have excellent academic track records (Bachelor of Science in Computer Science and Masters in Computer Engineering from the University of Toronto) along with strong development and industry experience in Software Development and Web Development (15+ years coding experience in total). I have helped more than 700 individuals here at CodeMentor (with 3,590+ 5 ★ sessions) with their projects implementation, bug fixes, architecture advices, performance improvements etc. I have worked with a bunch of CEOs and CTOs of YC start-ups and helped them with their projects. Made long term relationships with many of them which I help in a regular basis today. I have helped a ton of bootcamp students here at CodeMentor and helped them build their web development career path and getting jobs after the completion of their bootcamp cohorts. Here at CodeMentor, I have helped people from all levels: From someone who is brand new to programming to 30+ years of experienced Senior Software Engineers, Product Managers and everyone in between. It's been an amazing journey here at CodeMentor for the last 8+ years! :-) I started programming and solving problems in 2006, at the age of 18. Since then, I wrote programs in a variety of programming languages such as C, C++, Java, PHP, Ruby, Python, Javascript, etc. These days, I use Ruby and Rails and React JS as my primary programming languages and frameworks. I can help with debugging your issues as well as refactoring your code according to the best practices and conventions out there. Helping people is my passion and motto in life. If you think I can help you in any way, please get in touch! Specialties: * Building scalable and performant backend APIs in Ruby on Rails (Active Model Serializer, GraphQL, Grape, Jbuilder, RABL, etc.) for android, iPhone or web applications. (For more than 12 million users). * Integration of backend APIs with Javascript frontend framework (ReactJS) using JSON Web Token (JWT). * Built highly scalable Push Notification System for theScore sports application (For ~10 million users). * Implemented instant player, team and news article search for the theScore and theScore eSports apps which have more than 6 million monthly active users using ElasticSearch and Rails. * Backend Ruby on Rails Development (With scaling, performance optimizations, database query optimizations, caching best practices, etc.). * Test Driven Development with clean code and best practices. * Web Scraping (Nokogiri, Mechanize) (Scrape data from anywhere on the internet!). * Reverse engineering complex APIs and web applications to write automated scripts to mimic and automate user behaviour and extract required data. * Explain concepts/solutions clearly and concisely according to the level of the client/student. (Helped over 700 people on CodeMentor with 3,590+ 5 ★ sessions) * Giving architecture advice for your application. Explain which tools/gems to use and why. * Setting up SSL certificates for Rails application (Nginx server) on AWS EC2 instance and securing your application. * Suggesting best practices and focusing on the best learning experience and long-term achievements. * Showing cool tips and tricks that I have learned over the past 15+ years (and still learning!) as a professional Ruby on Rails developer to be more productive and efficient at work. * Upgrading Ruby/Rails versions for your existing application. * Finding bottlenecks and Optimizing performance for your slow Rails applications. * I can help you to prepare for interviews for Ruby on Rails developer position, or any other Software Development position. I have successfully guided many developers who got their dream jobs after practicing coding interviews with me!

Back-EndAWS (Amazon Web Services)RSpecHerokuJavaScriptReactAPIRubyRuby on RailsReverse EngineeringReduxReact NativeSinatraWebpackElasticsearchMySQLPostgreSQLGitGraphQLOmniAuthStripe

Hey! I am Johnny B. 🙏 (Actually, my Romanian friends call me Ionică, which in English is basically: Johnny). ...and I 💖 emojis! I started coding around 2010, starting with simple static websites, WordPress applications, and then tried Node.js for the first name around 2012. Since then, I have been working with Node.js. I like it a lot. Currently, I do the best in: ★ Node.js 🚀 ​ ​ ☆ Command line tools ​ ​ ☆ Express.js ​ ​ ☆ Passport ​ ​ ☆ Raw/minimal code, without frameworks (e.g. simple HTTP server) ​ ​ ☆ Using npm ​ ​ ☆ Creating npm packages for Node.js (and for the front-end as well) ​ ​ ☆ Scraping the web ​ ​ ☆ Automation of repetitive tasks ​ ​ ☆ Image processing ★ JavaScript ✨ ​ ​ ☆ Creating and importing libraries ​ ​ ☆ jQuery (creating plugins, using them etc) ​ ​ ☆ Scraping ​ ​ ☆ Automation of repetitive tasks ​ ​ ☆ Publishing npm packages ​ ​ ☆ SVG (SVG.js, d3.js) ★ HTML & CSS 🎨 ​ ​ ☆ Fixing CSS quick issues ​ ​ ☆ Implementing mockups ​ ​ ☆ Making the page responsive ​ ​ ☆ SEO tips & tricks ★ Command line 💻 ​ ​ ☆ Shortcut tips ​ ​ ☆ Creating command line tools ​ ​ ☆ Using VIM & Tmux ★ Code Review 👀 ​ ​ ☆ I do code review offline, for Node.js, JavaScript, eventually CSS. ​ ​ ☆ Can be done in a live session as well. ​ ​ ☆ Security checks ​ ​ ☆ I point things that can be done in a better way ★ Using Git & GitHub/GitLab/BitBucket etc. 😸 ​ ​ ☆ Introduction to how Git works ​ ​ ☆ Using Git hosting services (e.g. GitHub, GitLab, BitBucket etc) ​ ​ ☆ Top Git commands ​ ​ ☆ Shortcuts If I can help, I will definitely do it, as long your app is not promoting things that tend to be potentially immoral. For example, I'm happy to help you build an e-shop, but I will probably not build an e-shop designed specifically for selling wine since I am against the use of alcohol for drinking. ♦ 🚀 Node.js: 9 years of experience, ~700 packages published on NPM ♦ 💛 JavaScript: 9 years of experience, lots of libraries you can download freely (https://goo.gl/ewoQsK) ♦ 🗣 Fluent in speaking English & Romanian, and comfortable in Spanish & Portuguese ♦ 😸 GitHub Enthusiast (follow me: https://github.com/IonicaBizau) ♦ 😻 Git & GitHub power user ♦ 🍀 Comfortable with MongoDB (especially, the native driver for Node.js) ♦ ❇️ I will not charge you if I can't fix your issue. Why you can trust me: ★ I am a vegetarian. I have never eaten meat. 🍍🥑🥗 ★ I have never drunk wine, beer, etc. Water is the best. 💧 ★ I work for 6 days, and I rest on the 7th day. That's why I am *not* available on Saturdays (specifically between Friday's sunset and Saturday's sunset, my location at the time—you can my timezone a little bit below). 🙏 ★ I sleep between 9:18 PM and 4:42 AM. Depending on your timezone I can wake up earlier if you book a session with me. 💤 ★ I am a musician (pianist and organist). 🎹 ★ I use VIM on macOS and Linux. 🐧🍏

Back-EndGoogle apisCLISecurity softwareReactMongoDBNode.jsJavaScriptjQuerySVGHTML/CSSHTMLVimCSSGitFirebaseCOBOLShell

Reach out anytime at david@objective.enterprises I am a React and TypeScript engineer with over 10 years experience. My specialties are absolute beginners, small businesses, and aspiring engineers. I have guided hundreds of students into their first development job. I provide full support to development job-seekers, from mock interviews to career coaching. I can help you fix bugs quickly and fully understand each part of the solution. I offer tutoring services including, bootcamp support, long-term mentoring, and a complete educational experience. I have directed teaching programs and led classroom instruction in fullstack development, professional strategies, and game development. I also started without a formal background in computer science. I know you can cross that gap in an engaging, accessible, and fun way. Everyone that wants to make great software should be able to. I can help you learn to make apps with the features you want and explain exactly how they work. If you want to become a professional software engineer or entrepreneur and are eager to gain the necessary knowledge, I would be honored to help you improve your understanding, code, or career. I can help you assemble and manage a team of developers or coach you through an individual project. I offer pair-programming, consulting, and architectural planning alongside direct management and training. I can help key contributors or entire teams deliver features and understand how their solutions work. I can guide decision makers through complicated technical challenges to confidently determine the best course of action.

Back-EndExpress.jsFirebaseGame DesignGameChakra UINoSQLTypeScriptSocket.IOjQueryJavaScriptReactNode.js