Даниил

Daniil O.
Full-Stack Developer

Full-Stack Developer with 3+ years of experience building scalable web applications and APIs using modern JavaScript/TypeScript
technologies (React, Node.js, NestJS), with solid skills in database design (MongoDB, PostgreSQL/MySQL), real-time integrations,
and cloud tooling (Docker, AWS), focused on clean, efficient and maintainable code.

SKILLS SUMMARY TECHNOLOGIES

JS JavaScript / TypeScript
Node.js JavaScript, TypeScript
NestJS Node.js, NestJS, Express.js
React.js React.js
Express.js Web3.js, Ethers.js
RESTful APIs
English: Intermediate OOP, SOLID
Ukrainian: Native MongoDB, MySQL, PostgreSQL, NoSQL
Redis
TypeORM, Mongoose, Sequelize
Docker
AWS (S3, deployment)
CI/CD pipelines
Git
Socket.io
FFmpeg API
OpenAI API
Mailgun

PORTFOLIO

Addiction Tracker
Addiction Tracker
Description: A backend system designed to support tracking and management tools for
combating various types of addiction. The platform enables users and administrators to
monitor progress, manage recovery plans, and organize supporting resources through a secure
and scalable server-side architecture.
Solution:
Provided project estimates, breaking down features into deliverables and helping align
scope, timelines, and technical approach with the team and the client.
Participated in project discovery and planning calls, уточняючи requirements, edge cases,
and integration needs.
Developed and maintained backend services in NestJS, focusing on clean modular
architecture and reusable components.
Implemented REST API endpoints for core platform features (tracking, management flows,
and administrative operations).
Supported infrastructure and deployment setup using Docker and AWS to ensure
consistent environments and reliable releases.
Role: Backend Developer
Technologies: NestJS, TypeScript, AWS, Docker

Cryptocurrency Wallet Extension
Description: Browser-based cryptocurrency wallet extension for secure storage, sending, and
receiving of digital assets.
Solution:
Developed backend logic for wallet creation, transaction signing, and key management
using Node.js.
Integrated blockchain networks (Ethereum / ERC-20) via web3 and ethers.js.
Implemented secure storage and encryption for private keys and seed phrases.
Built background services and communication logic between the extension UI and
blockchain layer.
Supported core wallet operations such as balance retrieval, transaction handling, and
network switching.
Role: Backend Developer
Technologies: Node.js, JavaScript, Docker
Prenta
Prenta
Description: A web service for selling household appliances with partner order management.
The platform supports product sales workflows and consolidates orders coming from multiple
partner sources, enabling centralized processing, delivery coordination, and status tracking.
Solution:
Developed an API proof of concept for an AI quote agent, including request/response flows,
prompt/response handling, and basic validation to support automated quote generation.
Implemented order aggregation from assigned partners: designed data flows to collect,
normalize, and persist partner order data into a unified internal format.
Integrated caching/queue-like patterns with Redis to improve responsiveness and stability
for partner-related operations (e.g., aggregation and status syncing).
Fixed and improved delivery-related functionality, addressing issues in delivery status
updates, edge cases in order lifecycle transitions, and overall reliability.
Worked with the team to align the POC and partner integrations with existing service
architecture, deployment constraints, and operational needs.
Role: Backend Developer
Technologies: Express.js, Docker, MySQL, Sequelize, OpenAI API, AWS S3, Redis

SBRE
SBRE
Description: A comprehensive web platform developed for a real estate agency in Dubai,
enabling management of broker teams, property listings, and business statistics. The system
supports internal operations (team performance, activity tracking, reporting) and external
integrations to streamline lead handling and listing workflows.
Solution:
Implemented backend and frontend fixes during active development, improving stability of
core workflows and resolving production issues across the stack.
Integrated WhatsApp communication flow to support messaging/lead interaction scenarios
and improve response handling for brokers.
Integrated Property Finder to synchronize listings/leads and ensure consistent data
exchange between the platform and the external marketplace.
Developed a full-location auto-suggest search (Dubai-focused), including optimized
querying and user-friendly suggestion output for fast property/location lookup.
Implemented buyer matching logic with area-based contact visibility rules, ensuring
brokers could access buyer contact details only within relevant assigned areas/permissions.
Built buyer archiving functionality with an “exclusive” option, enabling controlled access to
archived buyers and preventing conflicts across broker teams.
Worked with real-time updates using Socket.io for key operational events (e.g., status
changes, assignments, notifications) where applicable.
Supported CI/CD pipelines and Docker-based environments to keep deployments
consistent and reduce release friction.
Role: Full-Stack Developer
Technologies: NestJS, TypeScript, Docker, AWS, React.js, TypeORM, Socket.io, CI/CD pipelines

Voice Training
Voice Training
Description: A vocal training application that lets users record, process, and compare voice
recordings for practice and progress tracking.
Solution:
Implemented audio upload handling and processing flow for user recordings.
Built overlay/merge functionality to combine user audio with reference tracks using
FFmpeg.
Stored recording metadata and processing results in MongoDB (Mongoose).
Containerized the service with Docker for consistent FFmpeg execution.
Role: Backend Developer
 Technologies: NestJS, TypeScript, Docker, MongoDB, Mongoose, FFmpeg API

Brikje
Brikje
Description: Online store selling LEGO products with shipping and delivery management
handled through third-party carriers.
Solution:
Integrated PostNL and DHL APIs to create shipments, generate labels, and track delivery
statuses.
Implemented delivery workflow updates (status syncing, error handling, and edge-case
fixes) to keep orders consistent.
Managed shipping-related data storage and updates in MongoDB (Mongoose).
Containerized the service with Docker for consistent deployments.
Role: Backend Developer
Technologies: NestJS, TypeScript, Docker, MongoDB, Mongoose

Zenova
Zenova
Description: Cleaning application for train services, supporting operational workflows and
reporting for train cleaning activities.
Solution:
Implemented export of train cleaning and work reports to PDF and Excel formats.
Ensured correct data mapping, formatting, and filtering for generated reports.
Fixed edge cases to keep exports consistent across different report types.
Role: Backend Developer
Technologies: NestJS, TypeScript, Docker, MongoDB, Mongoose

Telegram bot service
Telegram bot service
Description: Service for generating and managing multiple Telegram bots used to operate a
large number of Telegram channels. Each bot had its own feature set for channel
administration and automation.
Solution:
Handled backend development of the service and core bot management architecture.
Implemented bot logic and workflows for channel operations (posting, moderation/support
actions, etc.).
Integrated Telegram Bot API via Telegraf, including webhook/polling setup and update
handling.
Built multi-bot management: provisioning, configuration, and separation of bot-specific
functionality.
Implemented channel assignment and management flows, ensuring bots could reliably
work with their designated channels.
Stored bot/channel configuration and operational data in MongoDB (Mongoose).
Role: Backend Developer
Technologies: JavaScript, Node.js, Express.js, MongoDB, Mongoose, Telegraf, Telegram Bot API

WORK EXPERIENCE
10.2025 - PRESENT Full-Stack Developer
OmiSoft

02.2025 - 10.2025 Backend Developer
Under NDA

06.2023 - 02.2025 Backend Developer
 Under NDA

EDUCATION

Telecommunications and Radio Engineering
Kremenchuk National University of Ostrohradskyi
Master's degree