Publication
JavaScript Best Practices and Tips by Toptal Developers
https://www.toptal.com/developers/javascript/tips-and-practices
Kris is available for hire
Hire KrisKris Powelski
Verified Expert in Engineering
JavaScript Developer
Tokyo, Japan
Toptal member since November 5, 2014
Bio
Kris is a passionate developer with a prodigal side. He programmed his first video game at the age of ten and dove into web development soon after. Kris loves to work with international teams to experience the world at his desktop and be a part of exciting projects.
Portfolio
MorphMarket
React, JavaScript, CSS, jQuery, Webpack, Bootstrap, Flask, Pyramid, Django, DB...
Exasol
React, HTML, CSS, Next.js, WordPress, JavaScript, DB, Back-end, Full-stack
CauseLabs
React, WordPress, PHP 7, JavaScript, Sass, Amazon Rekognition, DB, Back-end...
Experience
- JavaScript - 20 years
- PHP - 16 years
- TypeScript - 8 years
- Laravel - 6 years
- WordPress - 6 years
- React - 5 years
- Lumen - 3 years
- Python - 3 years
Work Experience
Front-end Developer
2021 - 2022
MorphMarket
- Developed a complex platform to showcase users' inventory of reptiles.
- Used React with hooks to deliver a desktop-like app UI.
- Designed a database and implemented a back end for user transactions and interactions using the Django framework.
- Helped design multiple screens to combine powerful interfaces and fun interaction with the app.
Technologies: React, JavaScript, CSS, jQuery, Webpack, Bootstrap, Flask, Pyramid, Django, DB, Back-end, Full-stack
Front-end Developer
2021 - 2021
Exasol
- Developed dozens of platform pages using the Next.js framework.
- Implemented multi-language features to adjust the platform for global markets.
- Solved the platform's performance issues to make it snappy and reduce the bandwidth.
Technologies: React, HTML, CSS, Next.js, WordPress, JavaScript, DB, Back-end, Full-stack
Senior Full-stack Developer
2020 - 2021
CauseLabs
- Implemented user experience techniques using React With Redux making the project smooth and appealing for the end user.
- Created a back-end API with headless WordPress for a wide range of features on both the user and administrative side.
- Employed Amazon's Rekognition API to read objects on the photos.
Technologies: React, WordPress, PHP 7, JavaScript, Sass, Amazon Rekognition, DB, Back-end, Full-stack
Senior Full-stack Developer
2019 - 2020
Duolingo
- Created multiple A/B tests for design choices and logic, using React, Redux, and Python to improve sales performance and ease of use.
- Assisted in developing the English Test UI using React by implementing a wide range of features, including audio functionality.
- Joined the acquisition team to improve login and registration flow, using OAuth 2.0 for 3rd-party services integration.
- Improved performance of the development process by optimizing the client's user tools.
- Suggested multiple UI changes to improve engagement and general impression.
Technologies: Bootstrap, Sass, Python, JavaScript, React, DB, Back-end, Full-stack
Laravel Developer
2018 - 2018
MCH Group
- Created three separate portals for artwork management.
- Developed a back end to use third-party services (like Cloudinary) efficiently and to save costs.
- Worked with several maps APIs to deliver the most flexible address matching experience.
- Designed the UI for smooth artwork matching.
- Created an extraordinary authentication workflow.
Technologies: Amazon Web Services (AWS), CSS, HTML5, JavaScript, Vue, PHP, Laravel 5, DB, Back-end, Full-stack
WordPress Developer
2018 - 2018
NCLD
- Created an interactive tool for school guidance.
- Developed a feature to manage education stats for each part of the USA.
- Worked on the back end to improve the admin user experience.
Technologies: CSS, HTML5, JavaScript, PHP, WordPress, DB, Back-end, Full-stack
API Developer
2017 - 2017
Origin Broadband
- Worked with the large SOAP API of a leading British telecommunications company.
- Converted an unstandardized web service to a RESTful API.
- Developed an SDK for other developers to use for easier API integration.
- Made the code plug-n-play to make sure application's growth becomes easily integrated in the API.
- Investigated the telecom industry to provide the best API solutions.
Technologies: MySQL, Laravel, SOAP, REST, DB, Back-end, Full-stack
API and Management Tools Developer
2016 - 2017
Social Sweethearts
- Created an administration tool for Facebook ad generation.
- Created an API for automated Facebook ad synchronization.
- Customized tools to achieve optimal ad cost and reach.
- Performed automated A/B ad testing.
- Guided other developers to integrate the new API to existing platforms.
Technologies: jQuery, JavaScript, Laravel, PHP, Facebook API, DB, Back-end, Full-stack
Web Developer
2015 - 2015
D&D Company
- Created a WordPress plugin to allow smooth Facebook to Google Analytics communication. This product is able to automatically read stats from all your Facebook ad accounts and export it to Google Analytics data set. Beautiful and simple.
- Utilized advanced features of both Facebook API and Google Analytics API.
Technologies: HTML5, Google Analytics API, Facebook API, WordPress, DB, Back-end, Full-stack
Freelance PHP Developer
2014 - 2015
Printing Technic (via Toptal)
- Implemented a custom HTML5 uploader and integrated it with OpenCart.
Technologies: Git, jQuery, OpenCart, PHP, DB, Back-end, Full-stack
Web Developer
2014 - 2014
All for Body
- Created a motivational game for people wanting to achieve their personal goals.
- Developed a platform for communication between professionals and customers.
Technologies: MySQL, jQuery, Git, Laravel, DB, Back-end, Full-stack
Freelance Web Developer
2012 - 2014
Independent
- Created a WordPress plugin used by a large broadcasting company for TV show scheduling.
- Contributed to a popular WordPress plugin, Stream, which makes it easier to track WordPress activity.
- Used Git to contribute to work as part of an international team.
- Prepared a presentation for an international audience about my own plugin concept.
- Created a flexible WordPress plugin for social sharing.
- Was invited to meet the team at a trip to Toronto, Canada.
- Developed the website for XHTMLized, the front-end department for a company providing on-demand talent.
Technologies: Less, MySQL, jQuery, Git, WordPress, DB, Back-end, Full-stack
Web Developer
2011 - 2012
Snowdog
- Developed a Magento integration plugin for a large shipping company.
Technologies: MySQL, jQuery, Magento, DB, Back-end, Full-stack
Web Developer
2008 - 2011
InterMedium
- Created a huge platform for people searching for apartments.
- Developed a popular website containing funny photos and videos.
Technologies: MySQL, JavaScript, PHP, DB, Back-end, Full-stack
Web Developer
2009 - 2009
Autopik
- Created an automator to prepare a huge database containing car details and parts.
Technologies: MySQL, PHP, DB, Back-end, Full-stack
Web Developer, Game Reviewer
2005 - 2008
Victory Games
- Created a dedicated CMS for authors.
- Published game reviews.
- Helped with design.
Technologies: MySQL, JavaScript, PHP, DB, Back-end, Full-stack
Project History
Telecommunications API for Origin Broadband
Brand new API for Origin Broadbands. Instead of registering the customers and updating the lines manually, these tasks became automatic with my API. That allowed Origin Broadband not only to save lots of time and money, but also to avoid human mistakes.
Facebook Ads Platform and API for Social Sweethearts
http://www.socialsweethearts.de/I've been entirely responsible for creating the platform and API for managing Facebook ads for Social Sweethearts. The ads were automatically imported from XML file with an option to edit every single aspect of them. These tools automated tasks that took many hours of work weekly.
Expressboard
Expressboard is a share and collaboration platform for creative souls. The entire code and technical support for this project, as well as some of the graphic design, is my work. Made on Laravel 5.3.
Scrabble
An HTML5 version of Scrabble, my private project, waiting for final release.
Fresh Fit
An administration tool for a catering company made with Laravel.
All for Body
A motivational game for people wanting to achieve their personal goals.
Robo Robok
A Gadu-Gadu (popular Polish communicator) bot, modular and extendable. It helps with things such as Scrabble vocabulary, HTML colors, BMI information, and generating QR codes.
Snake
A simple HTML5 game, both mouse and touchscreen friendly.
Stream
https://wordpress.org/plugins/stream/Planes have a black box, WordPress has Stream. When something goes wrong, you need to know how it happened.
Widely popular WordPress plugin.
Widely popular WordPress plugin.
Toptal React Academy
The Toptal React Academy is an exclusive learning program that teaches the React framework to select members of the Toptal network. After a month of study, all graduates are tasked with completing a 30-40 hour final project to build and deliver a React app from scratch.
Education
2007 - 2012
Master's Degree in Computer Science and Economics
Poznan University of Economics - Poznan, Poland
Certifications
DECEMBER 2020 - PRESENT
Toptal React Academy Graduate
Toptal, LLC
Skills
Libraries/APIs
React, Slack API, Facebook Marketing API, Google Analytics API, REST APIs, Laravel Elixir, Facebook SDK, X (formerly Twitter) SDK, Facebook API, Google API, X (formerly Twitter) API, jQuery, Vue, Amazon Rekognition
Tools
Gulp, Eclipse IDE, Slack, Composer, Postman, Homebrew, Terminal, Vagrant, Bitbucket, Subversion (SVN), Git, SmartGit, JSHint, Sublime Text, GitHub, Bower, Adobe Photoshop, Sublime Text 3, Webpack
Languages
CSS, HTML5, JavaScript, Sass, SQL, Less, PHP, TypeScript, HTML, Python 3, Python, PHP 7
Frameworks
Bootstrap, Lumen, Laravel Spark, Laravel 5, Laravel, Vanilla JS, Swagger, Redux, Tailwind CSS, Next.js, AngularJS, Kohana, Flask, Pyramid, Django
Paradigms
RESTful Development, PHP Standards Recommendations (PSR), Test-driven Development (TDD), Object-oriented Programming (OOP), Responsive Web Design (RWD), Agile Software Development, Model View Controller (MVC), REST
Platforms
MacOS, October CMS, Android, Windows, WordPress, iOS, Magento, OpenCart, Amazon Web Services (AWS)
Storage
Redis, HTML5 Web Storage, MySQL, DB
Other
Full-stack, CORS, WebSockets, Ajax, Single-page Applications (SPAs), Agile Software Testing, WordPress Plugins, Back-end, SOAP, Computer Science, Economics
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