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Michal Mikolajczyk, Blockchain Developer in Warszawa, Poland
Michal Mikolajczyk

Blockchain Developer in Warszawa, Poland

Member since September 17, 2014
Michal is a senior software engineer and community leader for Toptal Warsaw. He communicates well and takes the initiative needed to help startups scale. Michal writes clean, functional code, automates infrastructure, and enjoys coordinating and scoping tasks. A former digital nomad, Michal speaks at conferences, and writes articles for the Toptal Blog. His professional interests include blockchains and artificial intelligence.
Michal is now available for hire
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Portfolio

  • ThinkAlpha LLC
    JavaScript, TypeScript, CSS, HTML, React, Node.js, Fintech, Full-stack...
  • Scoutside, LLC
    Node.js, Heroku, MongoDB, PostgreSQL, Sentry, Nuxt.js, Vue, Stripe API...
  • Aventus
    TypeScript, Next.js, Solidity, React, Node.js, User Experience (UX), Back-end...

Experience

Location

Warszawa, Poland

Availability

Part-time

Preferred Environment

Google Cloud, Travis CI, GitHub, Kubernetes

The most amazing...

...app I've built was Nowness.com (via Airnauts), which was nominated for a Webby Award 2015, and won Pixel Award and Pixel Award People's Choice.

Employment

  • Senior Full-stack Developer

    2020 - 2022
    ThinkAlpha LLC
    • Added new features, integrated services, and fixed bugs in a real-time trading application for analysts and brokers.
    • Optimized the processing of large data sets which included resolving performance problems on the server side as well as in the browser.
    • Created libraries, modules, and reusable components applied across several products.
    • Processed big data sets on the server and client side and dynamically rendered different graphs and charts to display results.
    Technologies: JavaScript, TypeScript, CSS, HTML, React, Node.js, Fintech, Full-stack, System Architecture, DevOps, Communication, Front-end, Open Source, UX Architecture, Web Development, REST APIs, APIs, Distributed Systems, Big Data, Full-stack Development, Hardware, Architecture, Storybook, Databases, Data Reporting, Front-end Development, API Development, Jest, Linux Servers, Amazon CloudFront CDN, API Integration, Microservices, Enterprise Systems, User Interface (UI), Algorithmic Trading, Figma, Object-oriented Design (OOD), Object-oriented Programming (OOP), Object-oriented JavaScript (OOJS), Asynchronous Programming, Asynchronous Servers, WCAG 2, Jira, Compilers, Code Generators, OpenAPI, GitHub, CSS Grid, CI/CD Pipelines, HTML5, Express.js, CSS3, REST, RxJS, Agile, Design Patterns, JSON, JSON API, JSON REST APIs, Webpack, React Router, React Hooks, Testing, JSX, Jenkins, Amazon Web Services (AWS), Amazon S3 (AWS S3), MUI (Material UI), Solution Architecture, Trading, Cryptocurrency Exchanges, Data Engineering, Chart.js, Webhook, AWS CodeDeploy, AWS CodePipeline, NoSQL, Back-end Development, Web Applications, Speech to Text, Text to Speech (TTS), MERN Stack, Microservices Architecture, Minimum Viable Product (MVP), API Design, UX Design, UI Design, Web, Responsive, Project Management, Software Architecture, Natural Language Processing (NLP), QA Automation, Data Analytics, Push Notifications, Front-end Build Tools, Mobile, Responsive UI

  • Back-end Developer

    2021 - 2021
    Scoutside, LLC
    • Helped with the release of the product, namely the launch day event.
    • Developed day-1 patches and bug fixes, solved connectivity issues, etc.
    • Prepared a production package, connecting with third-party monitoring and error-tracking tools (Sentry).
    Technologies: Node.js, Heroku, MongoDB, PostgreSQL, Sentry, Nuxt.js, Vue, Stripe API, Google Cloud Platform (GCP), Databases, Mobile App Development, Front-end Development, API Development, Jest, API Integration, Microservices, Three.js, AWS Lambda, SQL, Asynchronous Programming, Shopify API, Shopify, Scrum, WCAG 2, Jira, Search Engine Optimization (SEO), Google SEO, HTML5, HTML5 Animations, User Interface (UI), Online Ordering, eCommerce, CSS3, Unit Testing, Cypress, REST, Agile, JSON, REST APIs, JSON API, JSON REST APIs, Webpack, Content Management Systems (CMS), Solution Architecture, Loom, MySQL, Vue 3, Back-end Development, Cloud Firestore, Web Applications, Minimum Viable Product (MVP), API Design, Styled-components, Stripe Checkout, Web, Payment APIs, Responsive, Technical Leadership, Project Management, Digital Payments, Data Analytics, Push Notifications, Front-end Build Tools, PWA

  • Senior Full-stack Developer

    2021 - 2021
    Aventus
    • Built a decentralized application that was used for trading art NFTs on Ethereum blockchain.
    • Communicated between the decentralized application and smart contracts to manage auctions.
    • Displayed NFT images and videos to users participating in auctions.
    Technologies: TypeScript, Next.js, Solidity, React, Node.js, User Experience (UX), Back-end, REST APIs, APIs, Distributed Systems, Full-stack Development, Hardware, Architecture, Stripe API, Google Cloud Platform (GCP), Databases, Front-end Development, API Development, Jest, Digital Banking, API Integration, Crypto, Microservices, User Interface (UI), Non-fungible Tokens (NFT), MetaMask, Web3.js, Rinkeby, Algorithmic Trading, SQL, Object-oriented Design (OOD), Object-oriented Programming (OOP), Object-oriented JavaScript (OOJS), Asynchronous Programming, Asynchronous Servers, GraphQL, Scrum, Search Engine Optimization (SEO), Google SEO, GitHub, Serverless Architecture, CI/CD Pipelines, HTML5, Ethereum, Smart Contracts, Express.js, Online Ordering, eCommerce, CSS3, Unit Testing, Cypress, REST, Agile, Design Patterns, JSON, JSON API, JSON REST APIs, Webpack, React Router, React Hooks, Testing, JSX, Jenkins, Redux RTK, Solution Architecture, Trading, Data Engineering, Webhook, AWS CodeDeploy, AWS CodePipeline, NoSQL, Back-end Development, Web Applications, MERN Stack, Microservices Architecture, Minimum Viable Product (MVP), API Design, Styled-components, Stripe Checkout, UX Design, UI Design, Web, Lightning Network, Cryptocurrency, Payment APIs, Responsive, Video.js, Video Players, Payment Gateways, Technical Leadership, Project Management, Software Architecture, Digital Payments, Blockchain Platforms, Push Notifications, Front-end Build Tools, Responsive UI

  • Lead Engineer

    2020 - 2020
    Slidegrin, LLC
    • Set up serverless JAM stack application architecture on AWS Amplify.
    • Connected user pools with AWS IAM roles to manage users with AWS Cognito, in a multi-tenancy environment, including role-based access control permissions.
    • Set up live synchronization between sessions using GraphQL subscriptions with AWS AppSync.
    • Built an image manipulation editor supporting HTML Canvas with SVG and allowing exporting to raster and vector formats including PDF.
    • Established CI/CD pipelines with Amazon Amplify, CodeBuild, and CodeDeploy.
    • Built the serverless front-end app using Next.js and React with TypeScript.
    • Established unit and integration testing strategies with Jest, Enzyme, and the React Testing Library.
    Technologies: Amazon Web Services (AWS), SVG, Canvas, React, Serverless, AWS AppSync, Amazon DynamoDB, Amazon Cognito, AWS Amplify, TypeScript, System Architecture, Full-stack, DevOps, Next.js, Jamstack, Communication, Front-end, UX Architecture, REST APIs, APIs, Full-stack Development, Architecture, Vue, Storybook, Stripe API, Firebase, Databases, Front-end Development, API Development, Jest, API Integration, Microservices, User Interface (UI), AWS Lambda, Amazon API Gateway, Video Streaming, WebGL, SQL, Figma, Object-oriented Design (OOD), Object-oriented Programming (OOP), Object-oriented JavaScript (OOJS), Asynchronous Servers, GraphQL, WCAG 2, Jira, Search Engine Optimization (SEO), Google SEO, Team Leadership, Management, CSS Grid, Serverless Architecture, CI/CD Pipelines, Mobile Apps, HTML5, HTML5 Animations, CSS3, Amazon SageMaker, Cross-platform, REST, Agile, Design Patterns, JSON, JSON API, JSON REST APIs, Webpack, React Router, React Hooks, Testing, JSX, Amazon S3 (AWS S3), Content Management Systems (CMS), Solution Architecture, Webhook, AWS CodeDeploy, AWS CodePipeline, NoSQL, Back-end Development, Web Applications, Microservices Architecture, API Design, Styled-components, Flux Architecture, QA Testing, Stripe Checkout, UX Design, UI Design, Web, Vercel, Responsive, Mobile Applications, Technical Leadership, Project Management, Software Architecture, Cross-platform App Development, QA Automation, Data Analytics, Quasar, Front-end Build Tools, PWA, Mobile, Subscriptions, Responsive UI

  • CIO

    2018 - 2020
    Multichain Ventures
    • Developed web apps using React, Node.js, and Vue, among others.
    • Built iOS and Android mobile apps using Expo and React Native.
    • Developed blockchain decentralized applications using Waves, Ethereum, and Quorum blockchains.
    • Built a payment service provider API to be used by our merchants' clients.
    • Managed a team of up to six engineers as a C-level executive and created information and technology strategies.
    • Introduced engineering standards, including Gitflow, CI, unit testing, and containerization.
    • Introduced in-app user behavior monitoring based on funnels, user acquisition, retention, and monetization.
    • Developed integration mechanisms, relying on open-source technologies.
    • Implemented supply-chain visibility tools using standards.
    Technologies: Blockchain, Kubernetes, JavaScript, System Architecture, Full-stack, DevOps, Next.js, Communication, Front-end, Open Source, React Native, REST APIs, APIs, Stripe, Stripe Subscriptions, Distributed Systems, Full-stack Development, Hardware, Architecture, Bootstrap, Ant Design, Google Cloud Platform (GCP), Databases, Mobile App Development, Tailwind CSS, Front-end Development, API Development, Jest, Linux Servers, CTO, Digital Banking, API Integration, Crypto, Microservices, User Interface (UI), Binance API, Non-fungible Tokens (NFT), MetaMask, Web3.js, Rinkeby, SQL, Figma, Object-oriented Programming (OOP), Object-oriented JavaScript (OOJS), Asynchronous Programming, Asynchronous Servers, GraphQL, Shopify API, Gatsby, Shopify, Selenium, Search Engine Optimization (SEO), Google SEO, Code Generators, OpenAPI, GitHub, Team Leadership, Management, CSS Grid, CI/CD Pipelines, iOS, Mobile Apps, HTML5, Ethereum, Smart Contracts, PayPal API, Express.js, CSS3, Cordova, Android, Amazon SageMaker, Unit Testing, Cypress, Cross-platform, Jasmine, Protractor, REST, Karma, RxJS, Agile, Design Patterns, JSON, Auth0, JSON API, JSON REST APIs, Webpack, React Router, React Hooks, React, Testing, JSX, Jenkins, Back-office System Development, Ionic, Amazon Web Services (AWS), Redux RTK, MUI (Material UI), Content Management Systems (CMS), Solution Architecture, Flutter, MySQL, Data Engineering, Chart.js, Webhook, NoSQL, Back-end Development, Cloud Firestore, Web Applications, MERN Stack, Microservices Architecture, Minimum Viable Product (MVP), API Design, Styled-components, QA Testing, UX Design, Web, Chakra UI, Lightning Network, Cryptocurrency, Payment APIs, Vercel, Responsive, Mobile Applications, Payment Gateways, Technical Leadership, Project Management, Software Architecture, Digital Payments, Blockchain Platforms, Cross-platform App Development, QA Automation, Data Analytics, Push Notifications, Front-end Build Tools, Mobile, Subscriptions, Responsive UI

  • Co-founder

    2018 - 2020
    Reli.cloud
    • Managed hundreds of applications on AWS and the Google Cloud Platform.
    • Administered Kubernetes clusters and set up and managed an Istio service mesh.
    • Built an eCommerce storefront with a Vue storefront with PWA technology.
    • Automated processes, including monitoring and alerting.
    • Introduced site reliability engineering principles.
    • Adopted apps to cloud native computing by building and running them using containers.
    • Delivered a highly available platform as a service.
    Technologies: Site Reliability Engineering (SRE), Istio, Kubernetes, System Architecture, Full-stack, DevOps, Communication, Front-end, Open Source, React Native, REST APIs, APIs, Stripe, Stripe Subscriptions, Distributed Systems, Full-stack Development, Hardware, Architecture, Storybook, Stripe API, Google Cloud Platform (GCP), Databases, Data Reporting, Mobile App Development, Ant Design, Tailwind CSS, Front-end Development, API Development, Linux Servers, Amazon CloudFront CDN, NGINX, CTO, Digital Banking, API Integration, Crypto, Microservices, NestJS, Three.js, Cadence, Sanity CMS, Binance API, Vue, Amazon API Gateway, AWS Lambda, Asynchronous Servers, Gatsby, GitHub, Team Leadership, Management, Serverless Architecture, CI/CD Pipelines, HTML5, HTML5 Animations, PayPal API, User Interface (UI), Online Ordering, eCommerce, CSS3, Unit Testing, Cypress, Cross-platform, Jasmine, REST, Karma, Agile, JSON, Auth0, JSON API, JSON REST APIs, React Router, React Hooks, Testing, React, JSX, Jenkins, Back-office System Development, Ionic, Amazon Web Services (AWS), Content Management Systems (CMS), .NET Core, Microsoft SQL Server, ASP.NET, Microsoft Azure, Solution Architecture, R, Pandas, Loom, Robinhood, Flutter, Data Engineering, Webhook, Strapi, Back-end Development, Cloud Firestore, Web Applications, MERN Stack, Microservices Architecture, Minimum Viable Product (MVP), API Design, Flux Architecture, Stripe Checkout, UI Design, Web, fp-ts, Chakra UI, Lightning Network, Google API, Zapier, Mobile Applications, Payment Gateways, Technical Leadership, Azure, Project Management, Software Architecture, Digital Payments, Blockchain Platforms, Cross-platform App Development, Push Notifications, Front-end Build Tools, DigitalOcean, Mobile, Subscriptions, Responsive UI

  • Lead Engineer

    2018 - 2018
    William Hill
    • Released a new product, led a team of developers, and worked closely with QA and BA.
    • Developed performance benchmarks and improved on them.
    • Maintained, documented, and released three applications in a corporate environment.
    Technologies: Cloud Services, React, JavaScript, Full-stack, Communication, Front-end, REST APIs, APIs, Full-stack Development, Bootstrap, Storybook, Firebase, Databases, Data Reporting, Front-end Development, Microservices, Enterprise Systems, SQL, Object-oriented Design (OOD), WebRTC, CI/CD Pipelines, Express.js, eCommerce, CSS3, Cross-platform, Protractor, REST, Karma, Agile, Design Patterns, JSON, React Redux, Jenkins, Back-office System Development, Webhook, Web Applications, Web

  • Founder | CEO

    2017 - 2018
    Viking Garage
    • Founded the startup, bootstrapping it for nine months and building a team of six people.
    • Released the product within the first three months.
    • Led development and oversaw 55,000+ lines of open-source code.
    • Organized a conference that resulted in the formation of an open source blockchain IoT project; presented at three international conferences.
    • Expanded the reach of the project from Poland to Spain, Portugal, and Indonesia within eight months.
    Technologies: Blockchain, System Architecture, Full-stack, Communication, Open Source, REST APIs, APIs, Stripe, Full-stack Development, Hardware, Architecture, Google Cloud Platform (GCP), Databases, Mobile App Development, Tailwind CSS, Google Maps, Front-end Development, Linux Servers, CTO, Crypto, Microservices, NestJS, Three.js, User Interface (UI), Non-fungible Tokens (NFT), MetaMask, Web3.js, Rinkeby, Algorithmic Trading, Amazon API Gateway, AWS Lambda, Video Streaming, SQL, Object-oriented JavaScript (OOJS), Gatsby, Selenium, Search Engine Optimization (SEO), Google SEO, GitHub, Team Leadership, Management, CI/CD Pipelines, Mobile Apps, HTML5, Ethereum, Smart Contracts, PayPal API, Webflow, CSS3, Android, Microsoft Access, Cypress, Karma, RxJS, JSON, Auth0, Ionic, R, Pandas, Loom, Robinhood, Cryptocurrency Exchanges, MySQL, Vue 3, Twilio, Twilio API, Web Applications, Svelte, Minimum Viable Product (MVP), API Design, UX Design, UI Design, Web, fp-ts, Haskell, Scala, PureScript, Lightning Network, Cryptocurrency, Vercel, Zapier, Mobile Applications, Elasticsearch, Internet of Things (IoT), Blockchain Platforms, Cross-platform App Development, Data Analytics, Translation, Quasar, Bower Front-end Dependency Manager, Atomic Design, PWA, DigitalOcean, Mapbox, Mobile, Subscriptions

  • Senior Software Engineer

    2016 - 2017
    Maxwell Health
    • Coordinated the work between different teams and team leaders. Worked simultaneously on four teams.
    • Planned, scoped, and groomed tasks for teams and peers.
    • Developed front-end components and back-end modules.
    • Set up the automated infrastructure; this involved DevOps (Docker, Terraform).
    • Planned the architecture and helped clarify peer communication.
    Technologies: Docker, PHP, DevOps, JavaScript, TypeScript, Full-stack, Communication, Front-end, APIs, Full-stack Development, Bootstrap, Angular Component Architecture, Angular, Firebase, Databases, Data Reporting, Angular Material, Front-end Development, PostgreSQL, Enterprise Systems, Asynchronous Servers, Selenium, WCAG 2, CI/CD Pipelines, Redux, Jasmine, Protractor, Karma, React Redux, Ionic, Angular Bootstrap, MySQL, Web Applications, Web, Google API, Bower Front-end Dependency Manager, Atomic Design

  • Software Engineer

    2012 - 2017
    Trewebs
    • Architected and developed a new client-side web application for an existing, settled organization with hundreds of thousands of users interested in the fashion industry and indie art in Western (English) and Chinese territories.
    • Architected and integrated six external databases into one system, a MongoDB/Elasticseach search engine for the Museum of Polish Jews; an AngularJS client and a Node.js/SQL API for an event calendar app used internally by the Museum of Polish Jews.
    • Developed an AngularJS client for LimeSurvey, an open source survey CMS that exposed an RPC API for a national university (Warsaw School of Life Sciences).
    • Collaborated with UI/UX designers for the purpose of designing and subsequently developing responsive, holistic front ends for Krytyka Polityczna (a major alternative journal) and Bankwatch (an IFI focused, international NGO).
    • Created and led a developer team, introducing Agile, Scrum, Kanban, behavior-driven design, and test-driven development methodologies into the workspace.
    • Collaborated as a Drupal developer on two subsequent projects for West Pomeranian Voivodship and Unizeto Technologies, integrating Drupal and Apache Solr.
    • Delivered a high-availability Drupal app and server environment for the Educational Research Institute (Ministry of Education); allow registration of all Polish schools and also to provide Microsoft Excel (VBA) tools to aid teachers.
    • Delivered two Drupal CMS-based projects for the Warsaw City Council and the Warsaw Zoological Garden: Wild Bird Refuge and CITES Convention sites and HD multimedia.
    • Designed and created Apache Solr search algorithms, used to drive the UX of a 2013 international MatEXPO, an international construction site machinery convention.
    • Architected, designed in collaboration with UI/UX artists, and developed a responsive AngularJS web app aimed at mobile devices for London beauty therapists.
    Technologies: Drupal, MongoDB, AngularJS, Node.js, JavaScript, Full-stack, Communication, Front-end, APIs, Full-stack Development, Hardware, Architecture, Angular Component Architecture, Firebase, Databases, Tailwind CSS, Google Maps, PostgreSQL, Linux Servers, Amazon CloudFront CDN, NGINX, CTO, User Interface (UI), Algorithmic Trading, Amazon API Gateway, Java, Game Development, Microsoft Access, SOAP, React Redux, Angular Bootstrap, Microsoft SQL Server, MySQL, Twilio, Twilio API, WASM, Svelte, UX Design, UI Design, Video Players, Elasticsearch, Symfony, Bower Front-end Dependency Manager, DigitalOcean, Mapbox

  • Senior React Developer

    2015 - 2016
    Praesens (via Airnauts)
    • Developed a React/Redux app from the ground up.
    • Introduced state-of-the-art technology and stable technology into a new project.
    • Architected the app structure, including the front-end codebase, front-end API proxy and server, deployment pipeline, and CI.
    • Translated and/or reused components from a prototype version, which was based on the Middleman JS framework.
    • Worked alongside the CTO, introducing best practices, robust solutions, to all aspects of the app, from UI/UX to API communication and authentication.
    Technologies: Babel, Webpack, JavaScript, Emacs, Redux, React, Full-stack, Communication, Front-end, Angular Component Architecture, Angular, Databases, PostgreSQL, Prisma, User Interface (UI), Video Processing, React Redux, Video Players

  • Lead UI Developer

    2015 - 2016
    MarketMuse
    • Entered an existing startup, introduced effective solutions, and then took the role of UI team lead.
    • Improved the end product, placing the UI team ahead of the curve.
    • Introduced a standard, predictable release schedule, based on a Git flow of develop, release, and production.
    • Built a highly effective team with specialized roles, allowing the members to gain complementary skills.
    • Introduced unit testing and E2E testing within a continuous integration environment.
    Technologies: Functional Programming, Scrum, Test-driven Development (TDD), GitFlow, AngularJS, Front-end, Bootstrap, Angular, Databases, Angular Material, PostgreSQL, Prisma, Bower Front-end Dependency Manager

  • Software Developer

    2014 - 2016
    Metavaluate (via Toptal)
    • Upgraded a legacy app in terms of structure, performance, design, user interface, and experience.
    • Used separate threads in the browser to achieve non-blocking, heavy filtering, and sorting of large data sets.
    • Added models and controllers on the API through Sails.js.
    • Added a caching layer through Redis.
    • Added support for unit and E2E tests and provided multiple tests to be included in a CI environment.
    • Continued support for the project as consultant.
    Technologies: Redis, MongoDB, Sails.js, AngularJS, JavaScript, Full-stack, Front-end, Angular, Angular Material, Video.js, Internet of Things (IoT), Translation, Bower Front-end Dependency Manager

  • Software Engineer

    2014 - 2016
    Airnauts
    • Architected and built a large AngularJS app used by hundreds of thousands of users every month, in English and Chinese.
    • Added support for different video and audio content providers.
    • Created a robust SEO solution, using lightweight web services and built with Go.
    • Provided configuration modules to the CMS, which allowed for the preparation of content to show in the client app.
    • Supported all modern devices, with multiple responsive break points.
    • Added integration with multiple social networking services, including several from China.
    • Added support for a recommendation service, through a light web service built with Go.
    Technologies: Media, Go, Node.js, AngularJS, JavaScript, Full-stack, Front-end, Angular Component Architecture, Angular, Angular Material, Google Maps, PostgreSQL, Prisma, NGINX, User Interface (UI), Video Streaming, SQL, WCAG 2, Video Processing, SOAP, Content Management Systems (CMS), Video.js, Translation

  • Software Engineer

    2015 - 2015
    Heffernans Insurance (via Toptal)
    • Architected a robust, reactive system and engineered a minimum viable product.
    • Designed multiple data- and workflow diagrams as well as system architecture schemas.
    • Generated insurance certificates in PDF form, on demand, and saved the copies to S3.
    • Created a demo splash page to generate PDFs; displayed the PDFs using Mozilla's PDF.js viewer.
    • Created two APIs, utilizing the facilities already in use by the end client, minimizing work on their side.
    • Designed and implemented data schemas, based on legal documents (insurance certificates).
    Technologies: Amazon S3 (AWS S3), PhantomJS, PDF.js, Heroku, AngularJS, Loopback, Node.js, QA Testing

  • Software Engineer

    2015 - 2015
    June20 (via Toptal)
    • Built a library for other developers to use, based on AngularJS.
    • Created an E2E test environment, including automated testing on iOS devices.
    • Provided automated documentation, unit tests, and demos.
    • Manually wired up advanced AngularJS functionality with reusable components, to be used by other developers.
    • Created robust workflows using Gulp, Selenium, and Browsersync.
    • Configured infrastructure on AWS (EC2, S3, IAM).
    • Communicated with and shared data to the iOS app (in a hybrid app environment).
    • Created a continuous integration and deployment environment with Travis CI.
    • Created Slack integrations.
    Technologies: PHP, Appium, iOS, Git, AngularJS, JavaScript, Games, Selenium, Code Generators, WebRTC, Mobile Apps, Cordova, Unit Testing, Jasmine, Protractor, QA Testing, Bower Front-end Dependency Manager

  • Software Engineer

    2015 - 2015
    Eyeadvise (via Toptal)
    • Improved and extended a legacy app consisting of several modules hosted on Google App Engine.
    • Fixed existing issues around the client app written in AngularJS. Added new, business-critical functionality.
    • Fixed issues around a simple Python API.
    • Created an E2E testing environment, connecting all the multiple modules and also external services.
    • Added E2E tests, created documentation, and supported the project through the development process.
    Technologies: Facebook SDK, Google App Engine, Python, AngularJS, Bootstrap, Flask, Pandas

  • Web Developer

    2007 - 2012
    Freelance
    • Created simple HTML-based websites.
    • Designed simple websites.
    • Developed mid-sized projects for local councils.
    • Provided a dynamic map of investment areas with detailed information, editable through Drupal CMS.
    • Supported projects and clients until they reached maturity and became stable businesses.
    Technologies: Drupal, CSS, HTML, Angular Component Architecture, Google Maps, WebGL, Microsoft SQL Server

  • Researcher | Analyst

    2007 - 2012
    Engagement Intelligence
    • Analyzed 30+ viral and marketing campaigns.
    • Performed analyses in international (English) and Scandinavian (Norwegian and Danish) territories.
    • Researched key users who have the most influence in their respective networks.
    • Worked on a variety of campaigns from entertainment (mainstream games and movies) to advanced technology projects (Windows Vista OS, Microsoft Dynamics, ASP.Net).
    • Chosen as employee of the month; delivered projects for Microsoft, Sony, Columbia Pictures, Nokia, O2, and Lionsgate among others.
    Technologies: Analysis

  • Clinical Neuropsychologist

    2010 - 2011
    Institute of Psychiatry and Neurology, Second Department of Neurology
    • Designed a quantitative clinical study based on empirical preapprehension and literature.
    • Chose the right clinical and scientific methodology.
    • Carried out clinical and scientific research parallel to clinical duties.
    • Analyzed and measured data using chosen, sound statistical tools under the supervision of a senior scientific employee.
    • Delivered a complete scientific/academic study with patients.
    Technologies: SPSS, Statistics, Data Science, Google, WCAG 2

Experience

  • Professional Development and Training

    I completed several online courses in technology.

    BerkeleyX (XSeries Big Data Courses, 2015)
    • Introduction to Big Data with Apache Spark
    • Scalable Machine Learning

    BerkeleyX (Certificate Courses, 2012-2013)
    • Artificial Intelligence, Part 1
    • Software as a Service, Part 1
    • Software as a Service, Part 2

    EdX (2012-2013)
    • MongoDB for Python Developers
    • MongoDB for Node.js Developers

  • Speaker at Nomad City Conference
    https://www.youtube.com/watch?v=MA70On5pzyE

    I was invited to give a speech at Nomad City Conference in Las Palmas de Gran Canaria in December 2016.

    My speech was about taking up the responsibility of leading those choosing the digital nomad lifestyle, including remote work.

  • Toptal Community Leader in Warsaw, Poland (2015)
    https://www.toptal.com/leaders

    I helped build the Toptal Community in Poland. It mainly consisted of organizing 10+ gatherings for the community in Warsaw, including two conferences. I also attended Toptal gatherings in other countries and remained in constant communication with several other leaders.

  • Webby Nominee 2015

    2015 Webby awards nominee for Nowness.com.

  • Pixel Awards Winner and People's Choice Award Winner (2015)

    I was the 2015 Pixel Awards winner and People's Choice Award winner in the category of Arts & Culture for Nowness.com.

  • AngularJS State/URL Decouplement
    http://stackoverflow.com/questions/23585065/angularjs-ui-router-change-url-without-reloading-state/24835569#24835569

    An invention allowing developers to change the URL without reloading the state using an AngularJS UI router.

  • High-availability Drupal App and Server
    http://eduentuzjasci.pl/

    I delivered a high-availability Drupal app and server environment for the Educational Research Institute (Ministry of Education); the project was designed to allow registration of all Polish schools and also provide Microsoft Excel (VBA) tools to aid teachers.

  • LimeSurvey AngularJS Interface

    An AngularJS client for LimeSurvey, an open source survey CMS that exposed an RPC API, for a national university (Warsaw School of Life Sciences).

  • The Vital Guide to React.js Interviewing

    Article on Toptal Resources, 600+ likes.

  • AngularJS Develop Job Description Template
    https://www.toptal.com/angular-js/job-description

    Job Template for AngularJS on Toptal Resources.

  • The Vital Guide to AngularJS Interviewing

    Article on Toptal Resources.

  • 11 Essential AngularJS Interview Questions
    https://www.toptal.com/angular-js/interview-questions

    Article on Toptal Resources.

  • The 9 Most Common Mistakes That Ionic Developers Make
    https://www.toptal.com/ionic/most-common-ionic-development-mistakes

    Assisted in writing the article for Toptal Blog.

  • The Vital Guide to Interviewing Ethereum Developers

    The Ethereum and Solidity recruitment 101, main article under https://www.toptal.com/ethereum

  • Blockchain Development Guide

    The introduction to understanding development on distributed ledger technologies

  • Blockchain, IoT, and the Future of Transportation: Understanding the Motoro Coin (Publication)
    https://www.toptal.com/ethereum/motoro-iot-in-transportation
    Open-source, IoT, and Ethereum smart contracts work together with a new utility coin to make transportation more accessible and reduce vehicle waste. In this article, Toptal Freelance Ethereum Developer Michał Mikolajczyk explains the motivations and methodology behind his startup's latest initiative.
  • Top 18 Most Common Mistakes that AngularJS Developers Make (Publication)
    https://www.toptal.com/angular-js/top-18-most-common-angularjs-developer-mistakes
    AngularJS is a very powerful framework. It is the third most starred repository on GitHub. It is not difficult to start using, but the goals that it is intended to accomplish demand comprehension. No longer can we ignore memory consumption, because it will not reset on navigation anymore. This is the vanguard of web development. Let’s embrace it!

Skills

  • Languages

    CSS, HTML, TypeScript, SQL, ECMAScript (ES6), JavaScript, HTML5, CSS3, Object-oriented JavaScript (OOJS), Solidity, Python, Go, PHP, GraphQL, Java, R, WASM, Haskell, Scala, PureScript

  • Frameworks

    Bulma, MUI (Material UI), Bootstrap, Express.js, Jasmine, Protractor, Ionic, AngularJS, Angular, Swagger, React Native, Next.js, Tailwind CSS, Jest, Video.js, Express.io, Apache Spark, Appium, Loopback, Sails.js, Flux, Redux, Linux OpenSuSe, Bootstrap 3, Django, Angular Material, NestJS, Selenium, Cypress, Svelte, PhoneGap, Famo.us, Nuxt.js, Ant Design, Flask, .NET Core, ASP.NET, Flutter, Symfony, Quasar

  • Libraries/APIs

    AWS Amplify, REST APIs, React, Selenium WebDriver, Node.js, Vue, API Development, JSON API, React Router, React Redux, Twilio API, Facebook API, Socket.IO, Restify, D3.js, Moment.js, jQuery, Stripe, Stripe API, Google Maps, Three.js, Binance API, Web3.js, Shopify API, OpenAPI, RxJS, Pandas, Google API, Facebook SDK, PhantomJS, WebGL, WebRTC, PayPal API, Chart.js

  • Tools

    Google Analytics, GitHub, Auth0, Mocha, Gulp, Git, Karma, JSX, Front-end Build Tools, Bower Front-end Dependency Manager, AWS AppSync, Amazon Cognito, Canvas, Babel, Expo.io, Webpack, Grunt, Yeoman, React Apollo, Prisma, Amazon CloudFront CDN, NGINX, MetaMask, Figma, Jira, Microsoft Access, Amazon SageMaker, Jenkins, AWS CodeDeploy, Stripe Checkout, SPSS, Travis CI, Emacs, Istio, Sentry, Zapier

  • Paradigms

    Unit Testing, Web Application Architecture, API Architecture, Web Architecture, RESTful Development, Continuous Integration (CI), Continuous Deployment, Test-driven Development (TDD), DevOps, Functional Programming, Agile Software Development, Scrum, Behavior-driven Development (BDD), Requirements Analysis, Microservices, Object-oriented Design (OOD), Object-oriented Programming (OOP), Asynchronous Programming, Search Engine Optimization (SEO), Management, Serverless Architecture, REST, Agile, Design Patterns, Microservices Architecture, Responsive, Data Science, Kanban, Extreme Programming, Testing, Jamstack, Cross-platform, UX Design, UI Design

  • Platforms

    Amazon EC2, Heroku, Blockchain, Amazon Web Services (AWS), Drupal, Kubernetes, Docker, Google Cloud Platform (GCP), Twilio, Web, Blockchain Platforms, Firebase, AWS Lambda, Ethereum, Linux, CentOS, Debian Linux, iOS, Shopify, DigitalOcean, Mobile, Google App Engine, PDF.js, Webflow, Android, Azure, Mapbox

  • Storage

    NoSQL, PostgreSQL, MySQL, Databases, JSON, SQL Architecture, Amazon S3 (AWS S3), Amazon DynamoDB, Redis, MongoDB, Google Cloud, Microsoft SQL Server, Cloud Firestore, Elasticsearch

  • Other

    Serverless, API Applications, Web Applications, Video Streaming, Software Architecture, Full-stack, Front-end, Back-end, Minimum Viable Product (MVP), Content Management Systems (CMS), UX Architecture, Code Architecture, Architecture, Styled-components, User Experience (UX), Team Leadership, Technical Leadership, Task Analysis, System Architecture, Open Source, Communication, GitFlow, IT Systems Architecture, Cloud, APIs, PWA, Progressive Web Applications (PWA), Full-stack Development, Hardware, Angular Component Architecture, Data Reporting, Front-end Development, API Integration, User Interface (UI), Asynchronous Servers, CSS Grid, CI/CD Pipelines, JSON REST APIs, React Hooks, Back-office System Development, Solution Architecture, Technical Writing, Webhook, Back-end Development, MERN Stack, API Design, QA Testing, Video Players, Responsive UI, Amazon Cognito User Pools, Identity & Access Management (IAM), Load Balancers, Payment APIs, Data Architecture, Apollo, Writing & Editing, Bitcoin, DApps, Distributed Systems, Tech Conferences, Community, Coordination, Conference Speaking, Public Speaking, Team Management, Task Scheduling, Task Automation, Task Flows, Leadership, Google Material Design, Big Data, Cordova, Site Reliability Engineering (SRE), Digital Currencies, ICO, Mobile App Development, Linux Servers, CTO, Digital Banking, Crypto, Enterprise Systems, Non-fungible Tokens (NFT), Rinkeby, Algorithmic Trading, Amazon API Gateway, Games, Gatsby, WCAG 2, Google SEO, Compilers, Code Generators, Mobile Apps, Smart Contracts, HTML5 Animations, Online Ordering, eCommerce, Angular Bootstrap, Loom, Trading, Vue 3, Data Engineering, AWS CodePipeline, Speech to Text, Text to Speech (TTS), Flux Architecture, fp-ts, Chakra UI, Cryptocurrency, Vercel, Mobile Applications, Payment Gateways, Azure Databricks, Decision Trees, Internet of Things (IoT), Digital Payments, Cross-platform App Development, QA Automation, Data Analytics, Translation, Push Notifications, Subscriptions, Artificial Intelligence (AI), Google, Statistics, Media, Cloud Services, SVG, Fintech, Machine Learning, Web Development, Stripe Subscriptions, Storybook, Cadence, Sanity CMS, Game Development, Video Processing, SOAP, Redux RTK, Microsoft Azure, Robinhood, Cryptocurrency Exchanges, Strapi, Lightning Network, Natural Language Processing (NLP), Atomic Design, Development, Analysis

  • Industry Expertise

    Healthcare, Project Management

Education

  • Master's Degree in Neuropsychology
    2005 - 2011
    University of Warsaw - Warsaw, Poland

Certifications

  • Big Data
    AUGUST 2015 - PRESENT
    University of California, Berkeley | via edX
  • Scalable Machine Learning
    AUGUST 2015 - PRESENT
    University of California, Berkeley | via edX
  • Introduction to Big Data with Apache Spark
    JULY 2015 - PRESENT
    University of California, Berkeley | via edX

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