Oleksandr P. — Full-Stack Javascript Engineer

Work Experience

Fullstack Developer, Saas Insiders

04/2024- 12/2024

• Developed and maintained both front-end and back-end solutions for web applications, integrating various third-party APIs and services.
• Implemented real-time features and data synchronization using Socket.IO and NestJS for efficient communication.
• Integrated OpenAI for AI-powered features and used LangChain to build and deploy language models.
• Built custom e-commerce functionality and integrated payment systems with Shopify, Stripe, and other third-party APIs.
• Built RESTful APIs using NestJS, Node.js, and TypeORM to handle data and services efficiently.
• Optimized database operations using MongoDB and MySQL for persistent storage, using Mongoose and TypeORM for data modeling.
• Ensured code quality and best practices by integrating ESLint and following coding standards.
• Integrated and maintained API documentation using Swagger and tested APIs via Postman.

Technologies:React, Typescript, SCSS, CSS, MaterialUI, Airtable, MongoDB, Mongoose, TypeORM, Socket.IO, OpenAI API, LangChain, NestJS, Node.js, Shopify, Wix, Chrome Extensions, Stripe, ESLint, MySQL, Markdown, Swagger, Postman, GitHub, Vite, Webpack.

Lead Frontend Developer, EU4UA

03/2023- 04/2024

• Led the migration of the EU4UA platform from a no-code/low-code Webflow setup to a custom React-based application, ensuring a seamless transition of user data and services.
• Collaborated with international volunteer developers (Capitol team), onboarded members, assigned tasks, and organized workflows to drive project success.
• Established CI/CD pipelines and conducted code reviews using GitHub Actions to maintain high-quality standards and efficient deployments.
• Played a pivotal role in feature development by meeting with co-founders, analyzing user requests, conducting research, and transforming ideas into technical solutions.
• Managed platform support by addressing user feedback, resolving bugs, and ensuring platform stability and usability.
• Monitored security issues in Cloudflare, proactively identified vulnerabilities, and implemented security measures to protect the platform and ensure data integrity.
• Integrated Airtable and Firebase services to streamline data management and improve the backend infrastructure.
• Utilized i18next for internationalization, enabling seamless multilingual support across the platform.
• Wrote and maintained comprehensive documentation for platform features, API integrations, and development guidelines to ensure knowledge sharing within the team.

Technologies:React, Typescript, Redux, Redux Toolkit, Firebase (Auth, Functions, Firestore), Ant Design (AntD), i18next, Tailwind CSS, GitHub, GitHub Actions, CI/CD, Webpack, Airtable, Jest, Cloudflare, Brevo, Swagger, Postman, ESLint.

Fullstack Developer, EU4UA

11/2022- 03/2023

• Maintained and improved the existing custom code and low-code infrastructure, including Webflow and n8n.
• Supported the platform by fixing bugs and ensuring smooth functionality for users.
• Implemented new features to enhance the platform's usability and adapt to evolving user needs.
• Collaborated with team members to align development efforts with the organization's mission and goals.

Technologies: Webflow, n8n, Firebase (Auth, Functions, Firestore), Airtable, Brevo, CSS, HTMLS, JavaScript, REST APIs.

Fullstack Developer, TensionX

04/2021-10/2022

• Developed and maintained web applications and Chrome extensions, focusing on front-end and back-end functionality.
• Implemented new features and optimized the performance of existing projects.
• Conducted research to identify the most effective solutions for application functionality and architecture.
• Ensured applications' security and ability to interact seamlessly with multiple APIs and databases.
• Collaborated with app development teams, including project and product managers, developers, and QA, to define issues, testing methodologies, and best practices.

Technologies: HTMLS, CSS, SCSS, React, Typescript, Node.js (Express), MongoDB, MySQL, Webpack, Chrome Extensions, Material UI, WebSocket, JavaScript.

Other experience, earlier work, consulting engagements

• Built several web applications with Next.js, implementing server-side rendering and static site generation.
• Worked with dynamic routing, API integration, and component-based architecture in Next.js projects.
• Gained experience with features like incremental static regeneration and deployment workflows.
• Explored advanced Next.js capabilities, including middleware, custom API routes, and serverless functions.
• Focused on optimizing performance and SEO for better application efficiency.
• Enhanced skills in React.js as the foundation for developing with Next.js.