Konrad Gadzinowski
Verified Expert in Engineering
JavaScript Developer
Łódź, Poland
Toptal member since August 10, 2017
Konrad is a highly skilled software developer with 11 years of experience delivering web and mobile applications across industries. He has created software solutions for multiple small and large companies, helping them generate combined revenue of millions of dollars. Konrad is a great team player and a proactive self-starter. He has the skills of a full-stack JavaScript developer, enabling him to see the whole picture and deliver projects faster and with higher quality.
Portfolio
Experience
- JavaScript - 9 years
- Front-end - 8 years
- Full-stack - 7 years
- TypeScript - 7 years
- SQL - 6 years
- Node.js - 5 years
- React - 4 years
- MongoDB - 3 years
Availability
Preferred Environment
Node.js, HTML5, TypeScript, CSS, Bash, Web, PHP, JavaScript, Full-stack, Git
The most amazing...
...thing I've created is an app that uses advanced machine learning to solve nesting and packing optimization problems in the furniture industry.
Work Experience
Full-stack Developer
Swiss-Mile Robotics AG
- Created a control panel for a robot dog using Node.js, TypeScript, and React.
- Added controlling robot dog with a PS5 controller via gRPC connection.
- Implemented multiple real-time video streams with WebRTC.
- Added a 3D view of the environment and the robot dog, with Three.js library.
- Visualized a stream of LiDAR points in the 3D view.
- Implemented a 2D environment map and added the ability to send a robot dog to the selected point.
- Added different navigation modes: patrolling, navigating to a specified point, and manual navigation with a PS5 controller.
- Implemented logging all robot events and showing them in a real-time terminal.
- Added caching and loading on network issues and robot states in Redis.
- Implemented controlling a remote camera via its API.
Full-stack JavaScript Developer
AllVoices Holding Co
- Developed a platform for managing clients' data from scratch, which is used by customer support agents.
- Integrated a single authentication system used by other web applications.
- Designed wireframes based on the text requirements.
- Created multiple custom UI elements in React, required to edit data structures.
- Implemented creation, reading, and modification of data using TypeORM and PostgreSQL.
Full-stack Developer
Blockchain Startup (via Toptal)
- Used Electron to build a desktop app for Windows and Mac that allowed users to easily use blockchain technology.
- Created a Node.js-based web app connected to the desktop app. It contained a login feature for users and administrators and enabled administrators to monitor the real-time activity of all desktop applications.
- Managed the back-end hosting on AWS using Ubuntu servers. The hosting environment supported the created web application and Nuts, a desktop auto-update server app.
- Researched and utilized desktop blockchain software, which could use different mining pools and GPU and CPU for processing.
- Used Bootstrap for the Swift creation of an admin web app.
- Implemented real-time data exchange between the user's desktop app and the admin's back end.
- Added the ability to auto-update the desktop app based on GitHub releases.
- Created a set of animated, reusable React components for the desktop and web apps.
- Added the ability to deploy a new web app version to production with a single terminal command.
- Implemented a payout system that enabled users to request payouts directly from the desktop app. These payout requests were sent to the admin panel, where they could be reviewed and either approved or rejected.
Front-end Developer
Beacon Ai - Aircraft Tracking Startup
- Developed an interactive simulation of a plane flight using React and Cesium.
- Established a connection between a web application and a WebSocket to receive a continuous data stream.
- Implemented live and past video and audio streaming through Amazon Kinesis.
- Created plane gauges and instruments using JavaScript canvas.
- Developed a complex React-based web application for aircraft and aircrew management.
Front-end Developer
Quantics Biostatistics (via Toptal)
- Implemented a complex, interactive grid editor using React.
- Added automatic UI generation in React based on the provided data.
- Worked with UI mockups to implement the expected front end.
- Added an automatic front-end build system that uses Webpack.
- Implemented multiple interactive elements with React, such as dialogs, toasts, popups, and modals.
Full-stack JavaScript Developer
Large US-based Self-driving Car Company (via Toptal)
- Developed web applications that mainly used the map view.
- Created complex UI interfaces using React for multiple internal tools.
- Worked on the back-end integration with a PostgreSQL database.
- Wrote tests for both the back and front end implementations.
- Helped develop web-based simulators and mapping applications.
Full-stack Web Developer
Buho (Contract)
- Developed a comprehensive real estate web application from scratch.
- Implemented an interactive map and added a grid of properties.
- Enabled sign-up with users' Google and Facebook accounts.
- Rolled out a full-fledged CMS system allowing administrators to entirely customize the UI in multiple languages.
- Implemented automatic page translation to specific languages using Google Translate.
- Added asynchronous loading of all elements into the application.
- Implemented an API interface to communicate with the mobile application.
- Created a reusable set of elements that sped up further development.
- Integrated the Stripe payment system into the application for secure and seamless online payments.
Freelance Full-stack Web Developer
Nextech (via Toptal)
- Implemented two-factor authentication.
- Added printing documents to PDF.
- Created an administrator panel.
- Improved security and general application architecture.
- Introduced asynchronous loading of elements and pages.
- Developed a document editor that allowed simultaneous work and saved ongoing changes in a history.
- Implemented Stripe payment system.
Freelance Front-end Developer
CivicLift (via Toptal)
- Created multiple UI components using React.
- Added multiple screens based on mockups.
- Implemented user flow for multiple cases.
- Improved database schema validation.
- Helped reach a crucial deadline on project delivery.
Software Engineer
TomTom NV
- Developed a map search engine back end using Java with Lucene library.
- Developed an app proxy using JavaScript and Node.js.
- Hosted an application on Amazon AWS cloud.
- Hosted an application on Azure cloud.
- Supported delivery of an application to major automotive companies.
- Created extensive documentation about online search service on a developer portal.
UI Engineer
Massive Interactive Media, Ltd.
- Created a UI layer for a video-on-demand application.
- Added a new feature that allowed users to download movies to their mobile devices and watch them later.
- Deployed a mobile application to iOS and Android using a single codebase.
- Implemented an option to easily customize the base application for future customers.
- Adapted a base video-on-demand application for smart TV use.
Mobile App Developer – Contract in London, UK
Insane Logic, Ltd. (Contract)
- Implemented a billing system in the mobile application.
- Added flow for games.
- Encrypted an embedded database.
- Designed embedded database structure.
- Gathered feedback from users regularly and improved the application towards the suggested direction.
Independent Software Developer
Reptile Mobile
- Created a collection of games for a marketing division of a large pharmaceutical company.
- Delivered a point-and-click game in JavaScript for a marketing company.
- Developed a music editor for Android.
- Built an application that solves cutting and packing problems in the furniture industry using machine learning.
- Created a nightstand clock and alarm for Android.
- Delivered a skeuomorphic timer for iOS.
- Built a task and calendar application for Android.
- Built and sold the brightness battery widget for Android.
- Developed a countdown widget for Android.
- Created and sold a photo editor for Android.
- Built and sold a BMI calculator for Android.
- Delivered a flashlight application for Android.
- Helped create a T9 keyboard for Android.
- Created an application that detects hemoglobin level in blood based on the shade of a blood sample.
- Delivered a bespoke productivity application for Android called To Do Timer.
- Built a base mobile application and administrator web portal for an audio book company.
- Created an action game about flying pigeons for iOS and Android using Unity framework and C#.
- Delivered a news aggregator for Android.
- Collaborated with multiple companies, large and small. Helped them to create great software and increased their combined revenue by millions of dollars.
Automation Design Engineer
Promet
- Designed automatic production lines.
- Helped create software for production automation machines.
- Worked with multiple large production organizations.
- Developed drivers for large industrial machines.
- Supported and developed automatic production processes.
Experience
Neudesk, The Best Website Builder for Small Business
https://neudesk.com/This platform offers free website creation and hosting, with a nominal commission on sales only.
Neudesk utilizes AI to generate initial website content tailored to your business, significantly reducing set up time. Features include easy integration with Stripe for immediate sales capabilities, options for a free subdomain or a custom domain at no extra cost, and the ability to personalize and update AI-generated content to reflect your brand better.
It is ideal for businesses looking to expand their online presence, Neudesk offers a seamless, efficient path to reaching more customers and achieving round-the-clock online sales.
Búho Home
The application features a robust CMS system that efficiently manages pages in multiple languages. Moreover, it incorporates an automatic translation functionality powered by Google Translate.
Heyluk | AI Blog Articles Generator
TimeZonely
With its user-friendly interface, it offers a customized experience, ensuring that you only see the relevant information without the need for complex time zone calculations.
Mp3 Ringtone Factory
http://www.youtube.com/watch?v=bseP4LTivLc&feature=youtu.beApplication features include:
• Play ringtones, alarms, notifications, and different audio media music tunes in MP3 and other audio tune formats
• Trim and edit audio to ringtones, alarms, notifications, and different audio media music tunes in MP3 and other audio tune formats
• Option to set the ringtone loop number
• Zoom options like zoom in, out, and show all
• Different skin colors
• Audio library with many sorting options
NestPack
http://www.youtube.com/watch?v=uJUKCHFA_Jg&feature=youtu.beThe app contains two modules:
• Nesting—cutting optimization: helps users reduce the number of sheets and prepare a final offer for their products
• Packing optimization: helps users estimate the minimal number of trucks required to transport a given cargo, being a convenient solution for almost every industry.
Tasks + Calendar Sync
https://www.youtube.com/watch?v=Mmulz5aKSZIUsers can use this single app to control their tasks and calendars from one point in their device. The app will synchronize across all your devices, keeping their tasks and events consistent wherever they are.
The application was sold in April 2014 to Firstegroup, Ltd.
Document Conversion Queuing Service
https://github.com/konrad-g/Document-Conversion-Queuing-ServiceThe technologies I used included JavaScript ES6, Node.js, Express, Socket.IO, and Angular.
Final Alarm Xtreme
https://www.youtube.com/watch?v=SOyRKy7qdfE&feature=youtu.beLeveraging the device's accelerometer, it monitors users' sleep cycles and attempts to rouse them during a light sleep phase before the scheduled alarm time. The app saves and analyzes your sleep data, enabling users to gain insights into their sleeping patterns and improve for better rest.
Final Countdown Widget
http://www.youtube.com/watch?v=vLGwa70w9BEWhether counting down or counting up to a specific event, this widget assists users in managing their tasks effectively. It displays the remaining time and days left, allowing users to stay on track. With the convenience of a built-in calendar, users can easily set the desired date for their countdown or count-up event.
My Timer HD
https://www.youtube.com/watch?v=-VM2v7N9lRIThis great productivity app enables users to:
• Set as many timers as they want
• Choose between 11 different app colors, and match the color of the app to their iPhone or mood
• Use 12 unique, beautiful timers, including stopwatches and kitchen timers
• Specify timer names, time to countdown, or date to count to
• Choose if they want to see count down or up
• Set snooze
• Choose from 13 different alarm sounds
• Enable vibration during alarm
Task Timer +
Search Flashlight LED
http://www.youtube.com/watch?v=sTpjiQ478b4&feature=youtu.beIt utilizes the device's camera LED as a flashlight, providing a reliable light source. Additionally, it offers a screen torch with customizable colors. For quick access, the app includes a widget.
It is a convenient standalone flashlight solution originally developed as an add-on for the Night Alarm Display application.
Night Alarm Display
https://www.youtube.com/watch?v=dD_WjRoxSJ8Notably, it keeps the screen continuously illuminated throughout. This app is an excellent alternative to traditional digital clocks, providing one of the most advanced and feature-rich alarm clock experiences. With its digital clock display, it enhances convenience and functionality for users.
Bad Pigeons
CBA News Reader
https://www.youtube.com/watch?v=IJ9dpUfYkhY&feature=youtu.beUsers can choose, read, and easily search the most famous newspapers with their mobile devices free of charge and in the fastest way possible.
T9 A Keyboard
https://play.google.com/store/apps/details?id=com.akeyboardQuick Pic Editor
https://www.youtube.com/watch?v=OCOUL6jeeGAThe application features include:
• Trimming photos
• Resizing photos
• Rotating photos
• Adjust brightness, contrast, and saturation
• Adjust sharpness and blur levels
• Add pixelate effect
• Change photo into meme
• Add border
• Different photo effects
The application was sold in April 2014 to Firstegroup, Ltd.
Proper Weight & Body Fat
https://www.youtube.com/watch?v=xNdw9-6zFvcBy inputting age, gender, and relevant measurements, users can determine their ideal weight.
The application was sold in April 2014 to Firstegroup, Ltd.
Brightness Battery Widget
https://www.youtube.com/watch?v=9fcmwk-I2hQThe application was sold in April 2014 to Firstegroup, Ltd.
Audiobook – Return To Marshalls Bayou
The mobile application cooperates with the back-end server that enabled an administrator to send messages about new audio books to all users, using Google Cloud Messaging technology.
Captive Castle
The game aims to find the relic stolen from the user's village. It takes place in a castle. Users start at the front door and go through the different rooms, picking up items to add to their inventory for later use.
Education
Master's Degree in Automatic Control and Robotics
Lodz University of Technology - Lodz, Poland
Bachelor's Degree in Mechanical Engineering
Lodz University of Technology - Lodz, Poland
Certifications
Financial Markets
Yale University | via Coursera
Design Patterns
University of Alberta | via Coursera
Object-oriented Design
University of Alberta | via Coursera
Service-oriented Architecture
University of Alberta | via Coursera
Software Design and Architecture
University of Alberta | via Coursera
Skills
Libraries/APIs
D3.js, Chart.js, Stripe, Stripe API, Socket.IO, jQuery, React, Node.js, REST APIs, JSON API, Moustache.js, Leaflet, WebRTC, Google Calendar API, Google Maps, Google Maps API, React Redux, FFmpeg, Shaka Player, React Navigation, React Router, Emotion Library, Web Audio API, Apache Lucene, Backbone.js, Underscore.js, Braintree API, Vue, Cesium.js, WebGL, Three.js, Web3.js
Tools
IntelliJ IDEA, Gulp, Git, Grunt, JSX, GitHub, SOLIDWORKS, Autodesk Inventor, Stripe Checkout, Packer, Auth0, Apache, Jira, Redux Toolkit, Sentry, CircleCI, InVision, Adobe Flash, NPM, Flash, Illustrator CC, Photoshop CC, Webpack, AutoCAD, GIS, Google Analytics, Microsoft Teams, AWS CloudFormation, MQTT
Languages
HTML, PHP, Bash, CSS, SCSS, TypeScript, Java, HTML5, JavaScript, Less, Objective-C, SQL, PHP 7, PHP 8, HaXe, C, GraphQL, Kotlin, C#, Swift, Python, C++
Frameworks
Express.js, JUnit, Swagger, Jest, Next.js, Laravel, .NET, NestJS, Ionic, Bootstrap, Angular, Play Framework, Redux, OAuth 2, Video.js, Nuxt.js, gRPC, Yarn, ASP.NET, Tailwind CSS, Electron, React Native, .NET Core, Laravel Livewire, Cypress, ASP.NET Core, Material UI
Paradigms
Test-driven Development (TDD), Unit Testing, Testing, Web Architecture, REST, Responsive Web Design (RWD), Responsive, Design Patterns, Agile, API Architecture, Agile Software Development, Scrum, Database Design, Automation, Microservices, MEAN Stack, UI Design, Concurrent Programming, DevOps, Requirements Analysis, Scalable Application, Search Engine Optimization (SEO), Automated Testing, Mobile Development, Mechanical Design
Platforms
Web, MacOS, Windows, Android, iOS, Linux, Blockchain, Amazon EC2, AWS Lambda, Amazon Web Services (AWS), Docker, Ubuntu, Mobile, Heroku, Duo, Kubernetes, Meteor, Mapbox, Azure, LAMP, Google Ads, Google Cloud Platform (GCP), DigitalOcean, Firebase, AWS IoT Core
Storage
PostgreSQL, Amazon S3 (AWS S3), JSON, Databases, Redis, NoSQL, MongoDB, SQLite, MySQL, Cloud Deployment, Elasticsearch, Microsoft SQL Server, Amazon Aurora, Azure Cloud Services, AWS Elemental
Industry Expertise
Cybersecurity, Web Design, Trading Systems
Other
Security, Writing & Editing, Web Development, Mobile App Development, Pixel Perfect, Architecture, Software Architecture, Front-end, Back-end, APIs, Full-stack, Web Components, Responsive UI, Technical Leadership, System Architecture, Ajax, CSS Grid, Software Design, Integration, API Integration, JSON REST APIs, Technical Writing, Full-stack Development, CTO, Page Speed Optimization, Solution Architecture, Minimum Viable Product (MVP), CSS3 Animation, Front-end Architecture, Single Sign-on (SSO), Styled-components, Cloud, Startups, Animation, Recommendation Systems, Third-party APIs, Algorithms, Cryptocurrency, Code Review, Web UI, Web UX, Web Usability, Design Systems, UI Components, Mechanical Engineering, OpenAI, AdminJS, RESTful Microservices, Business Applications, Data Architecture, Infrastructure Architecture, SaaS, User Interface (UI), A/B Testing, Analytics, Server Management, Leadership, CI/CD Pipelines, Data Visualization, User Experience (UX), HTML Email, Content Management Systems (CMS), UI Animation, Data Scraping, Software Analysis, API Design, API Documentation, Amazon RDS, Chakra UI, Video Players, Dashboards, Video Streaming, Vectors, OAuth, TradingView, Cloud Architecture, IT Security, Asynchronous I/O, Reverse Engineering, Storybook, Content Delivery Networks (CDN), HTTP Live Streaming (HLS), Apple Pay, Google Pay, Large Language Models (LLMs), Fine-tuning, Audio Streaming, Design, Serverless, 3D Modeling, Encryption, Obfuscation, Videos, Data Processing, Robotics, PLC, Financial Markets, SEO Tools, Streaming Data, Neural Networks, BrainTree, Genetic Algorithms, WebSockets, Scrum Master, Gatsby, Web Accessibility, Game Development, 2D Games, Board Games, Machine Learning, Web Scraping, MERN Stack, WebAssembly (Wasm), Speech to Text, Text to Speech (TTS), OpenAI GPT-3 API, Artificial Intelligence (AI), OpenAI GPT-4 API, Remote Team Leadership, Team Leadership, Generative Pre-trained Transformers (GPT), Web3, Zoho, Computer Vision, Material Design, AI Design, Akamai, React Admin
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