Denis Beklarov, Developer in Funchal, Portugal
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Denis Beklarov

Verified Expert  in Engineering

Bio

Denis has been a versatile developer since 2013, specializing in React Native, React, Redux, Node.js, and TypeScript. In addition to being a software entrepreneur, he has held several senior developer roles. His solutions include an eCommerce payment app, employee time tracking, digital access control, a hotel guest service, a mobile magazine app, and a test framework for a drone services company. Denis delivers excellence, especially when working in agile teams with structured processes.

Portfolio

Mothership Technologies, Inc.
React.js, TypeScript, NestJS, Front-end, Ant Design, React Query...
Navi Savi LLC
React Native, JavaScript, Expo, Node.js, Google Play Development...
Klarna
React Native, TypeScript, React.js, Mobile App Design, JavaScript...

Experience

Availability

Part-time

Preferred Environment

Slack, MacOS, iOS, Visual Studio Code (VS Code), React Redux, AngularJS

The most amazing...

...thing I've developed is a large, distributed time-tracking app, using Kubernetes, NestJS, and React for the web and React Native for mobile.

Work Experience

Full-stack Developer

2023 - 2024
Mothership Technologies, Inc.
  • Developed an internal logistics dashboard using React and NestJS.
  • Utilized microservices architecture with REST and Kafka for communication.
  • Implemented financial services and payments to ensure flawless financial processes.
Technologies: React.js, TypeScript, NestJS, Front-end, Ant Design, React Query, Styled-components, Storybook, GPT-4, Fintech Development, Apache Kafka, Back-end Developers, Integration, GraphQL

React Native Engineer

2023 - 2023
Navi Savi LLC
  • Assisted in updating the NaviSavi mobile app, a complex UGC travel video product. Revamped the React Native app, which had become outdated across numerous libraries, technologies, and coding standards.
  • Overhauled the entire navigation system, replacing outdated packages and addressing associated issues to enhance performance and optimize video playback speeds.
  • Refactored the video player and playback logic to enhance performance.
Technologies: React Native, JavaScript, Expo, Node.js, Google Play Development, App Store Development, React Native, iOS

Senior React Native Engineer

2020 - 2023
Klarna
  • Served on an Agile team as a senior React Native developer for this eCommerce shopping and payment company. The project is covered under an NDA.
  • Developed features for a React Native mobile application.
  • Applied a data-driven approach to product development decisions.
Technologies: React Native, TypeScript, React.js, Mobile App Design, JavaScript, Technical Leadership, Software Architecture, APIs, Front-end, Front-end Development, Mobile UI Design, Mobile UX Design, Mobile App Design, Android, Code Review, HTML, Figma, CSS, JSON REST APIs, Mobile App Design, Java, Storybook, UI Development, UI Design, UX Development, UX Development, Architecture, Fintech Development, Asynchronous Programming, Integration

CTO | Software Developer

2018 - 2020
App4business GmbH
  • Developed a distributed NestJS back-end, deployed with Kubernetes.
  • Created a React Native mobile app for employee time tracking.
  • Developed a React web app for employee time tracking.
  • Created a module to share Redux code between React and React Native apps.
  • Built a Slack-like platform and mobile apps for company chat.
Technologies: TypeScript, React.js, React Native, NestJS, MongoDB, Socket.IO, Redux, Redux Thunk, Redux-Saga, Redis, React.js, NoSQL, Mobile App Design, Next.js, JavaScript, Technical Leadership, Software Architecture, APIs, Full-stack, Front-end, Express.js, Front-end Development, Mobile UI Design, Mobile UX Design, Mobile App Design, Code Review, Team Leadership, Remote Team Leadership, RPC, Tailwind CSS, HTML, CSS, JSON REST APIs, Mobile App Design, Ant Design, React Query, Styled-components, WebSockets, Full-stack, Cypress, UI Development, UI Design, UX Development, UX Development, Architecture, D3.js, Back-end Developers, Asynchronous Programming, Integration

Senior Software Developer

2017 - 2018
FairFleet
  • Worked on an Angular front-end application in an Agile team for this drone services company.
  • Employed a Selenium-based testing framework with Protractor for end-to-end testing.
  • Used an Angular Material-UI framework to enable a smooth user experience.
Technologies: Angular, Angular Material, TypeScript, JavaScript, Technical Leadership, Software Architecture, APIs, Full-stack, Front-end, Front-end Development, Mobile UI Design, Mobile UX Design, Mobile App Design, Code Review, HTML, Figma, CSS, JSON REST APIs, Mobile App Design, UI Development, UI Design, UX Development, UX Development, Architecture, Asynchronous Programming, Integration

Senior Software Developer

2016 - 2017
BlueID
  • Developed a web front-end with Angular and TypeScript. BlueID offers digital access control solutions for physical locations.
  • Built a React Native application with TypesScript.
  • Developed a native iOS application with Swift and Objective-C.
Technologies: React Native, Angular, Swift, Objective-C, React.js, Mobile App Design, JavaScript, APIs, Full-stack, Front-end, Front-end Development, Mobile UI Design, Mobile UX Design, Mobile App Design, Code Review, HTML, CSS, JSON REST APIs, Mobile App Design, Full-stack, UI Development, UI Design, UX Development, UX Development, Architecture, Asynchronous Programming, Bluetooth, Integration

Founder | Software Developer

2016 - 2016
Vipy
  • Developed a mobile application for hotel guest management.
  • Built a platform for hotels to provide information feeds for their guests.
  • Developed an Angular front end for hotels to manage content on the platform that feeds information to guests.
Technologies: Angular, React Native, Go, Yii 2, TypeScript, Redux, AngularJS, Jenkins, Dokku, React.js, NoSQL, Mobile App Design, JavaScript, Software Architecture, AWS, APIs, Full-stack, Front-end, Express.js, Front-end Development, Mobile UI Design, Mobile UX Design, Mobile App Design, Code Review, Remote Team Leadership, HTML, CSS, Mobile App Design, WebSockets, UI Development, UI Design, UX Development, UX Development, Back-end Developers, Cloud Engineering

Founder | Software Developer

2013 - 2016
JORNL Media
  • Created a mobile app platform for seven Russian magazines.
  • Built a web platform for magazines, which shares content with mobile apps.
  • Created a layout generation tool for magazine content, using the Hugo static site generator that's written in Go.
Technologies: PHP, Objective-C, iOS, JavaScript, Python, Google Apps Script, Adobe InDesign, Hugo, MySQL, SQL, React.js, Mobile App Design, APIs, Front-end Development, Mobile UX Design, Code Review, Remote Team Leadership, Mobile App Design, UI Development, UI Design, UX Development, UX Development, WordPress Development, Back-end Developers

Bachelor's Thesis Student (Intern)

2013 - 2013
BMW
  • Implemented a communication system for quality management.
  • Developed and rolled out a way for factory employees to read and share images.
  • Launched a pilot project in a Regensburg plant for over 150 manufacturing points.
Technologies: Visual Basic, .NET, React.js

App4business

A B2B platform for company communication, featuring CRM and chat modules. I built the microservices with Node.js and the front end with React and React Native. The platform was deployed with Kubernetes, and it uses REST and WebSockets for communication.

App4time

A time-tracking app for organizations, built with NestJS, React, and React Native. I developed this app with many features, such as real-time data updates via sockets, various approval workflows, calculations, and a very generic way to represent the company structure.

React Native App Optimization

https://www.ituloh.co/
I made improvements to the React Native application architecture to reach performance goals. My work included introducing an optimized FlatList and a Redux store, preloading videos, and using covers for a better user experience. I also rewrote the app navigation.

Full-stack Development | Fintech

https://www.vaya.finance/
During the fintech product's development, I carefully considered the end users' needs and aimed to create a highly secure, usable, and performant platform. To achieve this, I built a React front end that is intuitive and easy to use, guaranteeing a seamless and enjoyable user experience. Additionally, I implemented a Node.js back end that is highly scalable and reliable, ensuring the application runs smoothly at all times.

Both MongoDB and MySQL databases were used to store and manage data efficiently, enabling the application to handle large volumes of data without compromising performance.

Development of an iOS Application for a Men's Magazine

http://www.jornl.ru
Building an iOS application for a men's magazine was an exciting and challenging project. As a developer, I aimed to create a dynamic and visually appealing application that engages readers and provides them with an exceptional user experience.

To achieve this, I utilized the latest iOS development tools and technologies, including Swift, Xcode, and the Cocoa Touch framework. I created a well-designed and responsive user interface, integrating features such as push notifications, in-app purchases, and social media sharing.

In addition to creating a visually appealing app, I prioritized performance and optimized the application for speed and reliability. This involved paying careful attention to back-end functionalities, including data storage, retrieval, and analysis.

Ultimately, I was able to create an application that resonates with the target audience and enhances their reading experience. I achieved this by integrating rich multimedia content, interactive features, and seamless navigation. This well-crafted and aesthetically pleasing application makes readers feel engaged, informed, and inspired to read more.

City Guide Application for Fattal Leonardo Hotels

As a developer, I created a city guide mobile application for Fattal Leonardo Hotels, using React Native for the front end and Yii2 PHP for the back end. The app provides hotel guests information about tourist attractions, local events, and dining options, enhancing their travel experience.

I collaborated closely with the Fattal Leonardo Hotels team to understand their requirements and incorporated their feedback throughout the development process. I also ensured the application was user-friendly and easy to navigate, with a visually appealing interface.

To support the back end, I implemented a Yii2 PHP-based REST API to provide the mobile application with real-time data, ensuring easily accessible and up-to-date information on local attractions, events, and dining options.

Overall, the city guide application was a great success and served as a valuable tool for enhancing their guests' travel experiences. It was a pleasure to work on this project and contribute to the success of Fattal Leonardo Hotels.

Flutter Digital Waiter App

As a Flutter developer, I worked on a digital waiter app for a restaurant, allowing customers to easily browse menus, order food, and pay their bills using their smartphones.

The app is integrated with the restaurant's existing POS system and provides real-time updates on order status. It also includes features like customizing orders, tracking order history, and leaving feedback. The Flutter framework allowed for fast development and a seamless user experience across both Android and iOS devices.

Indonesia's Number One Commerce Video App

https://www.ituloh.co/
This project involved providing architectural consultation focused on improving performance for Ituloh, Indonesia's number one commerce video app. As a React Native architect, I introduced optimized components such as FlatList and implemented improvements to the Redux store. I also recommended the preloading of videos and the use of covers for a better user experience. Through these efforts, we achieved the desired performance goals and delivered a better experience for the app's users.

Libraries/APIs

React.js, Node.js, React.js, React Query, Redux-Saga, Google Maps Development, Socket.IO, FFmpeg, Stripe Development, D3.js

Tools

Redux Thunk, Figma, Slack Development, Adobe InDesign, AngularJS, Jenkins, Mongoose, Expo, React Native

Languages

TypeScript, Hugo, JavaScript, HTML, CSS, SQL, Swift, PHP, Objective-C, Python, Google Apps Script, Go, Visual Basic, Java, GraphQL

Frameworks

React Native, NestJS, Redux, Ant Design, Angular, Next.js, Express.js, Tailwind CSS, Cypress, Yii 2, .NET, Angular Material, Flutter UI, AngularJS

Paradigms

Mobile App Design, UI Design, UX Development, Asynchronous Programming

Platforms

Mobile App Design, iOS, Android, MacOS, Dokku, Azure Design, Docker, Firebase, Visual Studio Development, AWS, Apache Kafka, WordPress Development, Cloud Engineering

Storage

MongoDB, NoSQL, Redis, Neo4j, MySQL

Other

APIs, Front-end, Front-end Development, Mobile UI Design, Mobile UX Design, Mobile App Design, Code Review, JSON REST APIs, WebSockets, Full-stack, UI Development, UX Development, Back-end Developers, Full-stack, Technical Leadership, Software Architecture, Team Leadership, Remote Team Leadership, Maps, Styled-components, Storybook, Architecture, Fintech Development, Bluetooth, Integration, Mobile App Design, RPC, Videos, GPT-4, Google Play Development, App Store Development

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