Publication
Pay in, Pay out: How to Create a Marketplace
https://www.toptal.com/developers/ecommerce/create-a-marketplace-tutorial
Konrad is available for hire
Hire KonradKonrad Gadzinowski
Verified Expert in Engineering
JavaScript Developer
Łódź, Poland
Toptal member since August 10, 2017
Bio
Konrad is a highly skilled software developer with 14 years of experience delivering web and mobile applications across industries. He has created software solutions for multiple small and large companies, helping them generate a 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 to a higher standard.
Portfolio
AllVoices companies
PostgreSQL, React Admin, JavaScript, TypeScript, Full-stack, Node.js, AdminJS...
Swiss-Mile Robotics AG
React, Three.js, Leaflet, Web Audio API, Full-stack, HTML5, WebRTC, gRPC...
Blockchain Startup (via Toptal)
React, MongoDB, Stripe, MERN Stack, Node.js, Express.js...
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
Preferred Environment
Node.js, HTML5, TypeScript, CSS, Bash, PHP, JavaScript, Full-stack, Git, Agentic AI
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 JavaScript Developer
2023 - 2026
AllVoices companies
- 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.
- Implemented an AI phone line for receiving caller reports.
Technologies: PostgreSQL, React Admin, JavaScript, TypeScript, Full-stack, Node.js, AdminJS, React, Linux, REST APIs, Agentic AI, Claude Code, Claude, Cloud, Back-end Development, Distributed Systems, API Gateways, Google Cloud SQL, Google Kubernetes Engine (GKE), Memorystore, Technical Leadership, Integration, Call Tracking, System Architecture, Engineering Management, Anthropic, Cursor AI, OpenAI API, Software Development, Software Engineering, API Integration, Figma, CI/CD Pipelines, API Documentation, Full-stack Development, AI-assisted Development, LLM Integration, RabbitMQ, Scalability, Zoom
Full-stack Developer
2024 - 2024
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.
Technologies: React, Three.js, Leaflet, Web Audio API, Full-stack, HTML5, WebRTC, gRPC, WebSockets, Robotics, Node.js, TypeScript, JavaScript, Redis, Event-driven Systems, Proof of Concept (POC), Software Engineering, Performance Improvement, C++
Full-stack Developer
2022 - 2023
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.
Technologies: React, MongoDB, Stripe, MERN Stack, Node.js, Express.js, Amazon Web Services (AWS), Electron, Bootstrap, PostgreSQL, Amazon Aurora, Amazon RDS, Amazon EC2, WebSockets, Webpack, Databases, Database Design, CSS3 Animation, Web3, Front-end Architecture, Styled-components, Single Sign-on (SSO), OAuth, Linux, Identity & Access Management (IAM), Fintech, Forex, Software Development, ERP Systems, Data Engineering
Front-end Developer
2022 - 2022
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.
Technologies: JavaScript, TypeScript, Cesium.js, APIs, React, WebSockets, CSS3 Animation, Front-end Architecture, Styled-components, Storybook, Audio Streaming, Linux, Google Cloud Platform (GCP), REST APIs, Identity & Access Management (IAM), Google Cloud SQL, Proof of Concept (POC), Scalability, Data Engineering
Front-end Developer
2021 - 2021
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.
Technologies: JavaScript, React, ASP.NET, MySQL, Microsoft SQL Server, Webpack, CSS, HTML, D3.js, CSS3 Animation, Front-end Architecture, Linux, Interactive UI, Scalability
Full-stack JavaScript Developer
2019 - 2021
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.
Technologies: Web Development, Mapbox, Neural Networks, Concurrent Programming, Analytics, Design Patterns, Responsive, Responsive Web Design (RWD), REST, HTML, APIs, Yarn, NPM, Security, Docker, Google Maps, MongoDB, NoSQL, Ubuntu, SQL, SQLite, Swagger, Socket.IO, Express.js, Agile, Amazon Web Services (AWS), HTML5, CSS, Bash, Git, Web, Front-end, Full-stack, Back-end, React, Node.js, PostgreSQL, TypeScript, JavaScript, Next.js, GraphQL, Test-driven Development (TDD), Unit Testing, Testing, D3.js, Pixel Perfect, Chart.js, Microservices, RESTful Microservices, Web Architecture, Architecture, Software Architecture, Business Applications, Data Architecture, SaaS, User Interface (UI), Dashboards, Databases, Database Design, CSS3 Animation, Front-end Architecture, Styled-components, Automated Testing, React Redux, Storybook, Python, Linux, Data Processing, Google Cloud Platform (GCP), REST APIs, AI Agents, AI Integration, Contact Centers, Engineering Management, Django, API Architecture, API Design, Application State Management, Scalability, SDKs, Product Lifecycle Management (PLM)
Full-stack Web Developer
2017 - 2019
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.
Technologies: SEO Tools, Web Development, Concurrent Programming, Analytics, Server Management, Design Patterns, Responsive, Responsive Web Design (RWD), REST, HTML, Web Components, APIs, Stripe API, NPM, Security, Docker, Google Maps API, Google Maps, NoSQL, Bootstrap, Socket.IO, Express.js, Agile, HTML5, CSS, Bash, jQuery, Git, Web, Front-end, Full-stack, Back-end, Stripe, Gulp, MongoDB, JavaScript, SCSS, TypeScript, Node.js, NestJS, Stripe Checkout, Test-driven Development (TDD), Unit Testing, Testing, Pixel Perfect, Amazon EC2, Web Architecture, Architecture, Software Architecture, Data Architecture, SaaS, User Interface (UI), Page Speed Optimization, DigitalOcean, React Native, Databases, Database Design, CSS3 Animation, Front-end Architecture, OAuth, Single Sign-on (SSO), Linux, REST APIs, Identity & Access Management (IAM), Booking Systems, Responsive UI, Monitoring, Startups
Freelance Full-stack Web Developer
2017 - 2019
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.
Technologies: SEO Tools, Web Development, Concurrent Programming, Analytics, Server Management, Design Patterns, Responsive, Responsive Web Design (RWD), REST, HTML, Web Components, APIs, LAMP, NPM, Docker, MongoDB, SQL, Socket.IO, Express.js, Agile, HTML5, CSS, Bash, jQuery, Git, Web, Front-end, Full-stack, Back-end, Stripe, Security, Duo, MySQL, Node.js, PHP, JavaScript, Test-driven Development (TDD), Unit Testing, Testing, Pixel Perfect, Amazon EC2, Web Architecture, Architecture, Software Architecture, Business Applications, Data Architecture, SaaS, User Interface (UI), Page Speed Optimization, Databases, CSS3 Animation, Front-end Architecture, Linux, REST APIs, Application Security
Freelance Front-end Developer
2017 - 2017
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.
Technologies: SEO Tools, Web Development, Concurrent Programming, Analytics, Design Patterns, Responsive, Responsive Web Design (RWD), REST, HTML, APIs, Yarn, NPM, Security, MongoDB, NoSQL, Ubuntu, Socket.IO, Express.js, Agile, Node.js, HTML5, CSS, Bash, Git, Web, Front-end, Stripe, Meteor, React, JavaScript, NestJS, Test-driven Development (TDD), Unit Testing, Testing, Pixel Perfect, Web Architecture, Architecture, Software Architecture, Business Applications, Data Architecture, SaaS, User Interface (UI), Linux, REST APIs
Software Engineer
2015 - 2017
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.
Technologies: CSS, Mobile App Development, SEO Tools, Web Development, Mapbox, Concurrent Programming, Analytics, Server Management, Design Patterns, Responsive, Responsive Web Design (RWD), REST, IntelliJ IDEA, HTML, APIs, Swift, Elasticsearch, NPM, Security, Docker, Objective-C, Google Maps API, Google Maps, MongoDB, NoSQL, Ubuntu, PostgreSQL, SQL, SQLite, Swagger, Express.js, Agile, JUnit, Amazon Web Services (AWS), HTML5, Web, Front-end, Full-stack, Back-end, Bash, Packer, Git, Apache Lucene, Azure, Node.js, JavaScript, Java, Kubernetes, Test-driven Development (TDD), Unit Testing, Testing, Kotlin, Pixel Perfect, Microservices, RESTful Microservices, Amazon EC2, Web Architecture, Architecture, Software Architecture, Business Applications, Data Architecture, Infrastructure Architecture, SaaS, AWS Lambda, User Interface (UI), Databases, Database Design, Mobile, Linux, REST APIs, VoIP
UI Engineer
2014 - 2015
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.
Technologies: Mobile App Development, Concurrent Programming, Analytics, Design Patterns, Responsive, Responsive Web Design (RWD), REST, HTML, APIs, C, NPM, Security, UI Design, Ubuntu, SQL, SQLite, Swagger, Express.js, Agile, JUnit, HTML5, CSS, Bash, Git, Web, Front-end, HaXe, Objective-C, Java, JavaScript, Test-driven Development (TDD), Unit Testing, Testing, Kotlin, Pixel Perfect, Web Architecture, Architecture, Software Architecture, Streaming Data, Business Applications, Data Architecture, User Interface (UI), A/B Testing, CSS3 Animation, Video Streaming, Mobile, Front-end Architecture, Automated Testing, Audio Streaming, Linux, REST APIs
Mobile App Developer – Contract in London, UK
2014 - 2015
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.
Technologies: CSS, Mobile App Development, Concurrent Programming, Analytics, Design Patterns, Responsive, Responsive Web Design (RWD), REST, HTML, IntelliJ IDEA, APIs, Security, Agile, Bash, Git, Front-end, SQLite, Android, Java, Test-driven Development (TDD), Unit Testing, Testing, Pixel Perfect, Architecture, Software Architecture, Data Architecture, WebRTC, User Interface (UI), A/B Testing, CSS3 Animation, Mobile, Linux, SIP
Independent Software Developer
2012 - 2014
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.
Technologies: Mobile App Development, SEO Tools, Web Development, Underscore.js, Adobe Flash, InVision, Photoshop CC, Illustrator CC, Neural Networks, Genetic Algorithms, BrainTree, Play Framework, Google Calendar API, Concurrent Programming, Analytics, Server Management, Design Patterns, Responsive, REST, Web Components, APIs, Swift, ASP.NET, Stripe API, Braintree API, Stripe, Backbone.js, C#, Google Ads, Flash, LAMP, Security, Docker, Google Maps, Bootstrap, UI Design, Ubuntu, SQL, Agile, JUnit, HTML5, TypeScript, Bash, Git, Web, PHP, Front-end, Full-stack, Back-end, iOS, Android, jQuery, CSS, HTML, Objective-C, Java, JavaScript, Test-driven Development (TDD), Unit Testing, Testing, Laravel, .NET, Pixel Perfect, Amazon EC2, Web Architecture, Architecture, Software Architecture, Data Architecture, Infrastructure Architecture, SaaS, Ionic, WebRTC, User Interface (UI), A/B Testing, Page Speed Optimization, Databases, Database Design, CSS3 Animation, Mobile, Front-end Architecture, Single Sign-on (SSO), Automated Testing, Material Design, Linux, REST APIs, Identity & Access Management (IAM), Startups
Automation Design Engineer
2010 - 2012
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.
Technologies: Windows, PLC, C, SAP, SAP Fieldglass
Experience
Neudesk, The Best Website Builder for Small Business
https://neudesk.com/Neudesk is a cutting-edge website builder designed specifically for small businesses. It enables users to create and launch a professional online store in under ten minutes.
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.
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
Búho Home is a comprehensive web application for buying and renting real estate properties. Users can conveniently browse properties through a map and grid view. The payment system supports promo codes and is seamlessly integrated with Stripe. Additionally, users can sign up using their Google or Facebook accounts.
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.
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
Heyluk is a web application that utilizes artificial intelligence (AI) to generate blog articles swiftly and accurately. It produces technically precise and factually reliable content in minutes. Users sign up, input a topic, set preferences, and receive content that can be edited as needed. Heyluk provides original content with varied pricing plans and allows unrestricted commercial use of the generated material.
TimeZonely
An application that provides a solution to effortlessly view and compare multiple time zones simultaneously.
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.
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.beMp3 Ringtone Factory is an Android application that allows users to edit MP3, WAV, AAC, and AMR audio music media files and create ringtones, alarms, and notifications. It also enables editing alarms, notifications, tunes, and ringtone audio media files in MP3 and other audio tune formats.
Application 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
Application 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.beNestPack is a comprehensive app that solves nesting, cutting, and packing problems. Primarily developed for the furniture industry, it offers optimization solutions for various industries, including logistics. This app efficiently tackles all optimization challenges related to nesting, cutting, and packing, providing practical solutions for enhanced productivity.
The 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.
The 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=Mmulz5aKSZITasks + Calendar Sync brings the complete Google Tasks and Calendar experience to Android.
Users 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.
Users 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-ServiceIt's a small text conversion queuing service with real-time notifications and live status updates on the web interface.
The technologies I used included JavaScript ES6, Node.js, Express, Socket.IO, and Angular.
The 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.beFinal Alarm Xtreme is an intelligent Android alarm clock that facilitates a gentle wake-up experience.
Leveraging 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.
Leveraging 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=vLGwa70w9BEA countdown timer widget that adds a sense of urgency, excitement, and organization to the user's life.
Whether 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.
Whether 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=-VM2v7N9lRIMy Timer HD is an exceptional tool that brings the experience of real-world timers to users' iOS devices. With this app, they can interact with timers just as they would with physical devices, providing a seamless and immersive user experience.
This 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
This 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 +
Task Timer Plus is a unique productivity app for Android that combines the features of an agenda and to-do list with timers and graphs. It enables users to effortlessly visualize their day and track their progress, ensuring optimal time management. This all-in-one productivity tool allows users to stay organized and easily identify when they'll have dedicated time to accomplish tasks.
Search Flashlight LED
http://www.youtube.com/watch?v=sTpjiQ478b4&feature=youtu.beThe Flashlight app for Android devices is a straightforward yet handy tool.
It 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.
It 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_WjRoxSJ8The Night Display app for Android devices offers a fantastic nighttime experience by displaying clear hours and minutes on users' screens.
Notably, 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.
Notably, 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
A funny game where users can see the big world from the ground to the stars while playing the role of a city pigeon. It is an addictive, thrilling, action-packed flying adventure where users flap the little wings of the city pigeon that is ready to poop on everything he can!
CBA News Reader
https://www.youtube.com/watch?v=IJ9dpUfYkhY&feature=youtu.beCBA News Reader is a fast and powerful mobile news feed reader for the major newspapers of over thirty countries, including the USA, UK, Ireland, India, Canada, Australia, and Malaysia.
Users can choose, read, and easily search the most famous newspapers with their mobile devices free of charge and in the fastest way possible.
Users 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.akeyboardT9 keyboard was delivered for a London-based startup. The app offers different keyboard layouts including QWERTY and T9 layouts.
Quick Pic Editor
https://www.youtube.com/watch?v=OCOUL6jeeGAQuick Pic Editor is an app designed for quick shooting, editing, and sharing photos.
The 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.
The 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=xNdw9-6zFvcA BMI, waist-to-height ratio (WHtR), and body fat percentage calculator app designed to help users keep fit and manage their weight.
By inputting age, gender, and relevant measurements, users can determine their ideal weight.
The application was sold in April 2014 to Firstegroup, Ltd.
By 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-I2hQAn Android app that auto-adjusts the screen brightness based on battery level. It contains a widget that indicates battery level and screen brightness.
The application was sold in April 2014 to Firstegroup, Ltd.
The application was sold in April 2014 to Firstegroup, Ltd.
Audiobook – Return To Marshalls Bayou
An audiobook developed for Android devices using native technology.
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.
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
A point-and-click game made in JavaScript for both Android and iOS.
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.
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.
Tuttobanana
Tuttobanana is a playful web app that turns sending a banana into a tiny digital gift with a big feeling. Built with React and Firebase, it features animations, gamified gifting flows, and a live feed where bananas travel between people, making it a tiny social network in itself. It blends fun branding with real-time interaction to spread joy online.
RSTT: Reduce Screen Time Timer
https://play.google.com/store/apps/details?id=com.digitaljetty.rstt.reduce.screen.time.timerRSTT is an Android application that helps you reduce your screen time.
Do you reach for your device and suddenly realize an hour has passed?
RSTT puts a live timer right on your screen. It's always visible and impossible to ignore, so you stay aware of every minute you spend on your device.
Do you reach for your device and suddenly realize an hour has passed?
RSTT puts a live timer right on your screen. It's always visible and impossible to ignore, so you stay aware of every minute you spend on your device.
Restanaut
https://restanaut.com/Restanaut is an online ordering system built for restaurants. I created it from the ground up. Starting from the database design structure, going through all the back-end logic and architecture, and finishing on the client-side. I've also set up all the servers that the platform is hosted on.
RapDv
https://rapdv.com/Having developed multiple web applications, I've created a common underlying system for all of them and released it as a TypeScript framework. It consists of both server and client-side code. It enables a quicker, more reliable, and more repeatable process for creating web apps.
Education
2011 - 2013
Master's Degree in Automatic Control and Robotics
Lodz University of Technology - Lodz, Poland
2007 - 2010
Bachelor's Degree in Mechanical Engineering
Lodz University of Technology - Lodz, Poland
Certifications
MAY 2020 - PRESENT
Financial Markets
Yale University | via Coursera
MARCH 2020 - PRESENT
Design Patterns
University of Alberta | via Coursera
MARCH 2020 - PRESENT
Object-oriented Design
University of Alberta | via Coursera
MARCH 2020 - PRESENT
Service-oriented Architecture
University of Alberta | via Coursera
MARCH 2020 - PRESENT
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, OpenAI API, WebRTC, Google Calendar API, Google Maps, Google Maps API, React Redux, FFmpeg, Shaka Player, React Navigation, React Router, Emotion Library, Web Audio API, Firebase Web SDK, Apache Lucene, Backbone.js, Underscore.js, Braintree API, Vue, Cesium.js, WebGL, Three.js, Web3.js, Framer Motion, HubSpot API
Tools
IntelliJ IDEA, Gulp, Git, Grunt, JSX, GitHub, SOLIDWORKS, Autodesk Inventor, Claude Code, Claude, Amazon Connect, Figma, Zoom, Stripe Checkout, Packer, Auth0, Apache, Jira, Redux Toolkit, Sentry, CircleCI, Firebase Analytics, Google Kubernetes Engine (GKE), RabbitMQ, Microsoft Copilot, Microsoft Power BI, Microsoft AI, InVision, Adobe Flash, NPM, Flash, Illustrator CC, Photoshop CC, Webpack, AutoCAD, GIS, Google Analytics, Microsoft Teams, AWS CloudFormation, MQTT, SAP Fieldglass, RingCentral
Languages
HTML, PHP, Bash, CSS, SCSS, TypeScript, Java, HTML5, JavaScript, Less, C++, GraphQL, Objective-C, SQL, PHP 7, PHP 8, HaXe, C, Kotlin, C#, Swift, Python
Frameworks
Express.js, JUnit, Swagger, Jest, Next.js, Laravel, .NET, NestJS, Ionic, Bootstrap, Angular, Play Framework, Redux, OAuth 2, Video.js, Nuxt.js, gRPC, Windows PowerShell, Yarn, ASP.NET, Tailwind CSS, Electron, React Native, .NET Core, Laravel Livewire, Cypress, ASP.NET Core, Material UI, Django
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, Kubernetes, Blockchain, Amazon EC2, AWS Lambda, Azure, Amazon Web Services (AWS), Docker, Ubuntu, Mobile, Heroku, Microsoft, Microsoft Power Automate, Duo, Meteor, Mapbox, LAMP, Google Ads, Google Cloud Platform (GCP), DigitalOcean, Firebase, AWS IoT Core, HubSpot, MetaTrader, MetaTrader 5
Storage
PostgreSQL, Amazon S3 (AWS S3), JSON, Databases, Redis, NoSQL, MongoDB, SQLite, MySQL, Cloud Deployment, Google Cloud, Google Cloud SQL, Elasticsearch, Microsoft SQL Server, Amazon Aurora, Azure Cloud Services, AWS Elemental, Microsoft Entra ID
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, Payment Gateways, CSS Animations, SVG, Agentic AI, API Connectors, Identity & Access Management (IAM), Webhooks, Middleware, Back-end Development, Distributed Systems, API Gateways, Booking Systems, Call Tracking, Proof of Concept (POC), VoIP, Engineering Management, Anthropic, Cursor AI, Software Development, Software Engineering, AI-assisted Development, Application State Management, Interactive UI, LLM Integration, Monitoring, Prompt Engineering, AI Tools, Scalability, SDKs, Product Lifecycle Management (PLM), Data Engineering, Affiliate Marketing, Affiliate Tracking, Marketplaces, Payment APIs, Payment Processing, eCommerce, Vibe Coding, 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, AI Agents, AI Integration, Firebase Hosting, Firebase Cloud Functions, Event-driven Systems, Fintech, Forex, Contact Centers, SIP, Application Security, CRM, Microsoft 365, Microsoft Lists, ERP Systems, Performance Improvement, 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 (STT), 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, Lottie, SVG Animation, Mobile Apps, Bootstrap 5, SAP, Vendor Management, Memorystore, EMR, Electronic Medical Records (EMR), Genesys, NICE Systems, Webex
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