Michał Miszczyszyn, Full-stack JavaScript Developer in Gdańsk, Poland
Michał Miszczyszyn

Full-stack JavaScript Developer in Gdańsk, Poland

Member since July 25, 2016
Michal is a motivated full-stack JavaScript developer. He's focused on building lightweight, responsive, and semantic web apps with the use of modern technologies and standards. He loves pair programming and sharing his knowledge with coworkers. He also appreciates the Agile method, domain-driven design, and working with clients. Michal is an open-minded quick learner who's able to develop ingenious solutions when faced with obstacles.
Michał is now available for hire




Gdańsk, Poland



Preferred Environment

Git, Visual Studio Code, MacOS

The most amazing...

...thing I've done was a performance audit and refactoring of a web app (drawing graphs of hundreds of data points) and over 3x improvement in rendering time.


  • Full-stack JavaScript Developer

    2017 - PRESENT
    Online Freelance Agency
    • Developed sophisticated web applications for unique clients from all around the world.
    • Successfully led a team of five and built a product.
    • Implemented advanced filtering and searching SQL queries for PostgreSQL.
    • Optimized a React-based application.
    Technologies: Redux, React, Node.js, JavaScript, TypeScript
  • Freelance Front-end Web Developer

    2009 - PRESENT
    Freelance Work
    • Prepared multiple lightweight and responsive layouts with the use of the newest technologies.
    • Created multiple WordPress themes from PSDs.
    • Coded multiple WordPress plugins from scratch.
    Technologies: WordPress, PHP, jQuery, CSS3, HTML5
  • Full-stack JavaScript Developer

    2017 - 2017
    Tremor Technologies, Inc.
    • Created the front end of the application from scratch.
    • Prepared plans and estimations for the front-end codebase.
    • Implemented functionalities required for the new reinsurance marketplace application in Angular 2.
    • Created a REST API in Node.js for the purpose of demoing the application.
    Technologies: Hapi.js, Node.js, observables, RxJS, C3.js, TypeScript, Angular
  • JavaScript Developer

    2016 - 2017
    Move Technologies (via Toptal)
    • Implemented new features in a large AngularJS application.
    • Supported a legacy app in AngularJS.
    Technologies: Less, SCSS, CSS, HTML, AngularJS, JavaScript
  • Full-stack JavaScript Developer

    2015 - 2016
    Comet Lab
    • Implemented a performance audit for a web application, pinpointed key performance problems, and refactored the application in order to address these problems which resulted in over 3x rendering time improvement.
    • Created a WebRTC-based multi-user video chat application, including sound recording and transcription features.
    • Developed an interactive application for monitoring status of various devices and drawing graphs of hundreds of points per second using AngularJS and WebSockets.
    • Built a REST API in Node.js for a music-related startup.
    • Implemented new features in an existing React application.
    Technologies: WebSockets, PostgreSQL, Hapi.js, Node.js, Flux, React, AngularJS, TypeScript, JavaScript, CSS3, HTML5
  • JavaScript Developer

    2013 - 2015
    • Created a web application for Confr using AngularJS, and a REST API.
    • Developed a REST and WebSockets API using Node.js, WebSockets, MongoDB, and PostgreSQL.
    • Took over the development of an iOS application and delivered the finished product within a month.
    • Conducted code reviews of coworkers' work.
    • Communicated directly with business clients, created scenarios in order to fulfill all the requirements.
    Technologies: REST APIs, Objective-C, PostgreSQL, WebSockets, MongoDB, Node.js, AngularJS, JavaScript, CSS3, HTML5
  • JavaScript Developer

    2012 - 2013
    Oyatel AS
    • Created a web chat plugin for an existing Telco product.
    • Developed a JavaScript application and did research about the newest, bleeding-edge technologies.
    • Built a mobile application in Backbone.js.
    • Completed research and development of a webRTC-based video chat solution.
    • Created an interactive game platform for a JavaScript conference.
    Technologies: Strophe, XMPP, RequireJS, Backbone.js, jQuery, JavaScript, CSS3, HTML5


  • React-with-observable

    Use Observables with React declaratively!

  • Typesafe-hapi

    Type checking for Hapi.js based on Joi schemas!

  • Functional ORM

    A 100% typesafe SQL query builder.

  • Meet.js Summit 2018

    Meet.js Summit 2018 with over 500 people was the largest JavaScript conference organized in Poland. All the money from selling tickets was donated to a charity!

  • Meet.js Summit 2017

    Meet.js Summit 2017 with over 400 people was the largest JavaScript conference organized in Poland.

  • Type of Web

    Type of Web is a blog I've created. It's one of the most popular technical blogs in Polish.

  • Meet.js Summit 2013

    Meet.js Summit 2013 was a completely free JavaScript conference with over 300 attendees—the largest event of this kind ever organized in northern Poland.

  • Meet.js Gdańsk

    Free front-end meetups organized every two months. It consisted of three 10-minute presentations, food, and beer.

  • Toptal Mentor
    Michał is a mentor in the Toptal Global Mentor’s Program. This program is a partnership between Toptal and General Assembly to provide high quality mentorship for students from minority and low income backgrounds who are looking to begin their careers as professional software engineers. Michał shows commitment to diversity in tech by mentoring a General Assembly student every week for a year, covering everything from coding tips and tricks to advice on making it in the industry.


  • Languages

    JavaScript, HTML, CSS3, TypeScript, HTML5, SCSS, ECMAScript (ES6), Reason ML, OCaml, PHP, Objective-C, CSS, Less
  • Frameworks

    Flux, AngularJS, Hapi.js, Redux, Angular Material, Swagger, Angular
  • Libraries/APIs

    jQuery, REST APIs, React, Node.js, ReasonReact, C3.js, RxJS, Backbone.js, RequireJS, Strophe, WebGL
  • Tools

    GitHub, Sequelize, Git, Facebook Reason
  • Paradigms

    Behavior-driven Development (BDD), Test-driven Development (TDD), Kanban, Scrum, REST
  • Platforms

    MacOS, Visual Studio Code, WordPress
  • Storage

    JSON, PostgreSQL, MongoDB, MySQL
  • Other

    XMPP, WebSockets, observables, Domain-driven Design (DDD)


  • Bachelor's Degree in Computer Science
    2011 - 2014
    Gdańsk University of Technology - Gdańsk, Poland

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