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Kostyantyn S.

@KostyantynShv

monthly-level-three.svgverified-v2.svg
5,0
1
2,6
2,6
100%

Full-Stack Deveoper, React, Node.js

$18 USD / hora
・
Bandera de
Ukraine (2:56 p. m.)
・
Se unió el julio 17, 2024
$18 USD / hora
・
I'm a Full-stack JavaScript developer with 4+ years of commercial experience working on B2B and B2C projects.⭐ ➡️During this time, I've worked on various projects, ranging from crafting intuitive user interfaces for e-commerce platforms to architecting solutions for large enterprise platform. ❇️Developer experience❇️ • 4+ years of experience with React (Redux, Thunk, Saga). • 3+ years of experience with Next.JS, • 4+ years of experience with Node.js, Express, GraphQL • 4+ years in PostgreSQL, MySQL, MongoDB, Redis. • 2+ years experience with AWS ➡️Throughout my career, I've thrived in various roles, including team lead, tech lead, and individual contributor. My ability to navigate the complexities of web development, combined with my passion for innovation and commitment to excellence, has consistently delivered exceptional results for clients.
Verificaciones
A tiempo
100 %
Dentro del presupuesto
100 %
Freelancer Javascript Developers Ukraine
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Portafolio

Portafolio

12374730
In my recent project, I worked as a full-stack developer on a Multi-Tenant Scheduler App. On the frontend, I built the interface using Next.js (App Router), focusing on dynamic pages, various calendar views, and company settings that impacted other parts of the application. One highlight was implementing drag-and-drop functionality for managing shifts, creating an intuitive scheduling experience. I utilized Shadcn UI for component styling, Zustand for state management, Formik/Yup for complex forms, and SWR for optimized data fetching and caching. On the backend, I developed scalable services with NestJS. My work included: - Designing RESTful APIs for managing tenants, shifts, and calendar data. - Creating a multi-tenant architecture with PostgreSQL, ensuring data isolation and security. - Implementing JWT authentication and role-based access control for secure, tenant-specific interactions. - Adding real-time updates using WebSockets to keep scheduling data synchronized. -
"CrewHR" CRM
12374709
In my recent project, I developed a comprehensive Construction Management Platform with an AI-powered voice assistant using React and TypeScript. The application serves as a central hub for construction project management, featuring real-time activity tracking, task management, and intelligent scheduling assistance. One highlight of the project was implementing an AI assistant that helps construction superintendents manage projects through natural language interactions. The system processes voice commands to coordinate between contractors, automatically update project schedules, and manage construction activities in real-time, significantly reducing communication overhead and improving project coordination. Key technologies and tools I utilized include: Mantine UI for building a responsive and customizable interface with built-in RTL support and comprehensive component library. AG Grid for complex data visualization, including custom Gantt charts, progress tracking views, and filterabl
Management AI Platform "GEMBA"
12148134
As a React developer, I utilized Redux and Context API for state management to handle complex state interactions, such as order tracking and reservation management. Developed a responsive user interface using React and Tailwind CSS. Also, I integrated with RESTful APIs and GraphQL endpoints to manage data related to menu items, orders, reservations, and customer feedback. I worked closely with UX/UI designers to translate wireframes and design prototypes into functional React components.
Spice Pos (Senior React Developer)
12148129
I utilized React with Redux for managing complex state changes and Next.js for server-side rendering to enhance SEO and initial load times. I implemented Tailwind CSS to create a responsive, modern UI with a mobile-first approach. Custom components were styled for a consistent look and feel. I created a RESTful API using Node.js and Express. I implemented GraphQL to provide a more flexible and efficient querying mechanism, allowing clients to request only the data they need. Additionally, I integrated with payment gateway PayPal.
VER0 ( Full-Stack Development )
12350021
The CRM Penny system is designed to streamline the way brokers manage client interactions and financial information. I used Node.js to build the backend services that handle both manual and automated data entry. This includes creating RESTful APIs for data submission, processing, and retrieval. I did the backend interacted with a database system PostgreSQL to store and manage client data. Also, I developed APIs to support communication between the CRM system, website widgets, and any other external systems. These endpoints handle requests from brokers and clients, ensuring seamless data flow.
Penny CRM (Backend developer Node.js)
12148127
As a full-stack developer, I designed and implemented the front-end using React and TailwindCSS to ensure a responsive and user-friendly interface. Also, I developed back-end services with Node.js and Express, including RESTful APIs for product management and order processing. I integrated payment gateways and managed database interactions with MongoDB. I collaborated closely with the UX/UI designer to align the implementation with the design vision and ensure a consistent user experience. Participated in daily stand-ups and sprint planning meetings to track progress and address issues.
Full Stack Developer ( E-Commerce Marketplace Platform )
12374730
In my recent project, I worked as a full-stack developer on a Multi-Tenant Scheduler App. On the frontend, I built the interface using Next.js (App Router), focusing on dynamic pages, various calendar views, and company settings that impacted other parts of the application. One highlight was implementing drag-and-drop functionality for managing shifts, creating an intuitive scheduling experience. I utilized Shadcn UI for component styling, Zustand for state management, Formik/Yup for complex forms, and SWR for optimized data fetching and caching. On the backend, I developed scalable services with NestJS. My work included: - Designing RESTful APIs for managing tenants, shifts, and calendar data. - Creating a multi-tenant architecture with PostgreSQL, ensuring data isolation and security. - Implementing JWT authentication and role-based access control for secure, tenant-specific interactions. - Adding real-time updates using WebSockets to keep scheduling data synchronized. -
"CrewHR" CRM
12374709
In my recent project, I developed a comprehensive Construction Management Platform with an AI-powered voice assistant using React and TypeScript. The application serves as a central hub for construction project management, featuring real-time activity tracking, task management, and intelligent scheduling assistance. One highlight of the project was implementing an AI assistant that helps construction superintendents manage projects through natural language interactions. The system processes voice commands to coordinate between contractors, automatically update project schedules, and manage construction activities in real-time, significantly reducing communication overhead and improving project coordination. Key technologies and tools I utilized include: Mantine UI for building a responsive and customizable interface with built-in RTL support and comprehensive component library. AG Grid for complex data visualization, including custom Gantt charts, progress tracking views, and filterabl
Management AI Platform "GEMBA"
12148134
As a React developer, I utilized Redux and Context API for state management to handle complex state interactions, such as order tracking and reservation management. Developed a responsive user interface using React and Tailwind CSS. Also, I integrated with RESTful APIs and GraphQL endpoints to manage data related to menu items, orders, reservations, and customer feedback. I worked closely with UX/UI designers to translate wireframes and design prototypes into functional React components.
Spice Pos (Senior React Developer)
12148129
I utilized React with Redux for managing complex state changes and Next.js for server-side rendering to enhance SEO and initial load times. I implemented Tailwind CSS to create a responsive, modern UI with a mobile-first approach. Custom components were styled for a consistent look and feel. I created a RESTful API using Node.js and Express. I implemented GraphQL to provide a more flexible and efficient querying mechanism, allowing clients to request only the data they need. Additionally, I integrated with payment gateway PayPal.
VER0 ( Full-Stack Development )
12350021
The CRM Penny system is designed to streamline the way brokers manage client interactions and financial information. I used Node.js to build the backend services that handle both manual and automated data entry. This includes creating RESTful APIs for data submission, processing, and retrieval. I did the backend interacted with a database system PostgreSQL to store and manage client data. Also, I developed APIs to support communication between the CRM system, website widgets, and any other external systems. These endpoints handle requests from brokers and clients, ensuring seamless data flow.
Penny CRM (Backend developer Node.js)
12148127
As a full-stack developer, I designed and implemented the front-end using React and TailwindCSS to ensure a responsive and user-friendly interface. Also, I developed back-end services with Node.js and Express, including RESTful APIs for product management and order processing. I integrated payment gateways and managed database interactions with MongoDB. I collaborated closely with the UX/UI designer to align the implementation with the design vision and ensure a consistent user experience. Participated in daily stand-ups and sprint planning meetings to track progress and address issues.
Full Stack Developer ( E-Commerce Marketplace Platform )
Cambios guardados
5.0 · 1 Review
Opiniones
B
Paid Test Task • $200 USD
Kosyantyn did an outstanding paid task on the front-end project. His attention to detail, creative design approach, and expertise in optimizing user interfaces significantly enhanced the overall user experience. His work was not only visually appealing but also highly functional and efficient. Great job!
Bogdan R.
@bodrets
•
Bandera de
Dubai, United Arab Emirates
•
hace 5 meses
Compartir
Experiencia
Full-Stack Developer
sept, 2023 - jun, 2024
•
9 meses
Appexoft
sept, 2023 - jun, 2024
•
9 meses
As a Full-Stack Developer, I have had the opportunity to work on both the front-end and back-end aspects of web applications, ensuring seamless integration between the user interface and the server-side logic. My role involved building end-to-end solutions, from crafting intuitive user interfaces to designing robust backend systems.
Bandera de
Lviv, Ukraine
sept, 2023 - jun, 2024
•
9 meses
React Developer
feb, 2020 - ago, 2023
•
3 años, 6 meses
Freelancer
feb, 2020 - ago, 2023
•
3 años, 6 meses
As a React Developer, I have been responsible for designing, developing, and maintaining user interfaces for dynamic, high-performance web applications. My primary focus has been building responsive, scalable, and reusable components using React.js and related technologies.
Bandera de
kharkiv, Ukraine
feb, 2020 - ago, 2023
•
3 años, 6 meses
Educación
Nacional'nij Tehnicnij Universytet 'Kharkivskij Polytehnicnij Institut'
2020 - 2024
•
4 años
Bachelor of Accountancy (BAcc), Computer science
Bandera de
Ukraine
2020 - 2024
•
4 años
Calificaciones
Innovation Campus educational program for IT specialists
2020
Innovation campus
I mastered both front-end and back-end development, including modern frameworks and libraries like React, Next.js, Node.js, and Express. Understand web standards, responsive design, and user experience (UX) best practices.
2020
Certificaciones
SQL - Level 1
SQL
JavaScript - Level 1
JavaScript
US English - Level 1
US English
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