Oleksii Palii — Senior JavaScript (Node.js, React.js) Developer

Expertise in Back-End Web (4.0 yr.), Full Stack Web (4.0 yr.).

Last verified on February, 2026

Core Skills

Bio Summary

Engineer with 5+ years of experience specializing in JavaScript (Node.js, React.js) and TypeScript, delivering scalable backend services and responsive frontend applications.
Proficient in modern frameworks and tools including Nest.js, Express, Next.js, GraphQL, Docker, AWS (Lambda, Step Functions, SQS), and CI/CD pipelines.
Strong expertise in database management with PostgreSQL, MongoDB, DynamoDB, and Redis, implementing event-driven architectures and microservices.
Demonstrated ability to optimize performance, enhance security (AWS Secrets Manager), and integrate complex third-party APIs across diverse domains such as sports streaming, finance, task management, and fitness platforms.
Advanced academic background in Software Engineering and Cybersecurity, with ongoing PhD studies, underpinning a solid foundation in software development lifecycle, best practices, and engineering principles.

Technical Skills

Programming Languages	JavaScript, TypeScript
JavaScript Frameworks	Express, Ext JS, NestJS, Node.js, React
JavaScript Libraries and Tools	Immutable.js, Mobx, Mongoose, React Router, Redux, Redux-Saga
AI & Machine Learning	OpenAI
Security	Auth0
Databases & Management Systems / ORM	AWS DynamoDB, MongoDB, MySQL, PostgreSQL, Redis, Snowflake
UI Frameworks, Libraries, and Browsers	Ant Design, Material UI, Socket.io, Tailwind CSS
Cloud Platforms, Services & Computing	AWS
Amazon Web Services	AWS DynamoDB
Deployment, CI/CD & Administration	Axios, CI/CD
Virtualization, Containers and Orchestration	Docker, Terraform
Version Control	Git
SDK / API and Integrations	Google API, Google Maps API, GraphQL, RESTful API, Stripe, Twilio API
QA, Test Automation, Security	Jest
Methodologies, Paradigms and Patterns	microservices architecture
Logging and Monitoring	Sentry
Mail / Network Protocols / Data transfer	WebRTC, WebSockets
Other Technical Skills	NX

Work Experience

JavaScript (Node.js, React.js) developer - Company 1 (Sports streaming and entertainment platform)

Duration: 06/2022-06/2024
Summary: Leading global sports streaming service that offers live and on-demand sports content, providing a comprehensive and convenient way for sports enthusiasts to enjoy their favorite sports without traditional broadcast limitations.
Responsibilities:

Developing scalable and highly resilient backend services to manage the subscription lifecycle process using Node.js and TypeScript in AWS cloud environment.
Building robust backend solutions and conducting unit and integration tests.
Improving service monitoring by adding logging, metrics, and alerts using New Relic and AWS CloudWatch.
Collaborating with a multinational team including software engineers, architects, and specialists to deliver a compelling user experience.
Enhancing security posture and streamlining operations with AWS Secrets Manager integration.
Optimizing performance and reducing infrastructure costs through ARM64 architecture migration.

Technologies: Node.js, Nest.js, TypeScript, Express, Fastify, PostgreSQL, DynamoDB, Docker, CI/CD, Terraform, AWS, Event-driven architecture, NewRelic, OpenTelemetry

JavaScript (Node.js, React.js) developer - Company 1 (Platform for streamlining table operations)

Duration: 05/2021-06/2022
Summary: Map Finance (Emergent Layer) is a startup offering an automated platform for streamlining table operations, enabling integration with various data sources and allowing users to create reusable workflows with Python scripts, AI-generated scripts, or Excel functions.
Responsibilities:

Developing and maintaining both frontend and backend applications.
Managing databases and creating new endpoints, services, and UI elements.
Designing and implementing application architecture and business logic.
Integrating with third-party APIs for accounting, AI, CRM, HRIS, and ERP systems.
Coordinating with technical support to configure and set up accounts for comprehensive service integration.
Optimizing code through refactoring, reviewing, and applying design patterns.
Conducting code reviews and providing team support.

Technologies: Node.js, Nest.js, Redis, PostgreSQL, Stripe, Snowflake, WebSockets, Merge.dev API, Bull, Sentry, Google APIs, OpenAI, Docker, TypeScript, Next.js, MobX, React-Query, Auth0, CodeMirror, Handsontable, Stripe, Axios, Ant Design, Tailwind CSS, XLSX

JavaScript (Node.js, React.js) developer - Company 1 (Unified Task Management Platform)

Duration: 03/2020-05/2021
Summary: An innovative startup platform for unified task and project management, integrating with tools like Trello, Asana, Jira, Slack, and Google Calendar, allowing users to create custom workflows and collaborate efficiently.
Responsibilities:

Developing and maintaining frontend and backend applications.
Managing databases and creating new endpoints, services, and UI elements.
Designing and implementing application architecture and business logic.
Integrating with third-party APIs for project management, communication, and scheduling.
Coordinating with technical support for account configuration and service integration.
Optimizing code through refactoring, reviewing, and applying design patterns.
Conducting code reviews and supporting the team.

Technologies: Node.js, Express.js, MongoDB, PostgreSQL, Redis, WebSockets, Google APIs, Docker, TypeScript, Next.js, Redux, React-Query, Auth0, Axios, Material-UI, Tailwind CSS, XLSX

JavaScript (Node.js, React.js) developer - Company 1 (Virtual Fitness Platform)

Duration: 07/2019-03/2020
Summary: A pioneering startup virtual fitness platform connecting fitness enthusiasts and trainers for virtual workout sessions, integrating data from fitness trackers, health apps, diet plans, and performance analytics.
Responsibilities:

Developing and maintaining frontend components using React.js for a responsive user interface.
Implementing backend services with Node.js and Express.js to manage user data, workouts, and scheduling.
Designing and deploying MongoDB databases for user profiles, workout plans, and performance metrics.
Integrating third-party APIs such as fitness trackers, nutrition apps, and social media platforms.
Collaborating with fitness experts and UX/UI designers to enhance user experience.
Optimizing codebase through refactoring and performance tuning.
Conducting code reviews and providing feedback to ensure code quality.
Supporting technical support teams in user account configuration and issue resolution.

Technologies: Node.js, Express.js, MongoDB, Firebase, AWS S3, Stripe API, Twilio API, WebRTC, Socket.io, GraphQL, React.js, Redux, Material-UI, Styled Components, Axios, JWT authentication, Jest, CircleCI, Docker

Education

Master's degree VN Technical University Cybersecurity
taught in English/Ukrainian
full-time
PhD VN Technical University Software Engineering
full-time, taught in English/Ukrainian
2024 - 2028

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