Олександр

OLEKSANDR KALINICHENKO
Senior Full-Stack Engineer
Ukraine | [відкрити контакти](див. вище в блоці «контактна інформація») [відкрити контакти](див. вище в блоці «контактна інформація»)
[відкрити контакти](див. вище в блоці «контактна інформація»)

PROFESSIONAL SUMMARY
Senior Full-Stack Engineer with 6+ years of commercial experience building production web, mobile, AI, and gaming
systems. Strong in Node.js, TypeScript, React, Nest js, backend architecture, databases, infrastructure, and
production releases. Hands-on experience integrating LLM and Computer Vision services into real products, plus
current development of an independent Unity mobile game.

CORE SKILLS
Backend: Node.js, TypeScript, JavaScript, NestJS, Express.js, REST APIs, WebSocket, WebRTC,
microservices, event-driven architecture, message queues, background workers, authentication,
RBAC, third-party integrations, API documentation, validation, caching, rate limiting, logging,
monitoring, performance optimization

Databases: PostgreSQL, MongoDB, Redis, Firebase Firestore
Frontend: React, Next.js, React Native, TypeScript, JavaScript, HTML5, CSS3, responsive design,
component-based architecture, state management, REST and WebSocket integrations, authentication
flows, performance optimization

LLM / Generative AI: OpenAI API, GPT models, AI assistants, Retrieval-Augmented Generation
(RAG), embeddings, semantic search, prompt engineering, context management, structured outputs,
function calling, tool calling, conversational workflows, intent detection, entity extraction,
knowledge-base integration, response grounding, LoRA training, image generation

Computer Vision: Python, PyTorch, OpenCV, YOLO, human and object detection, 2D pose estimation,
keypoint detection, skeleton-based motion analysis, action recognition and classification, temporal
sequence analysis, movement trajectory analysis, technique assessment, multi-object tracking,
dataset preprocessing, model training and evaluation, inference optimization

Game Development: Unity, C#, procedural generation, hex-grid systems, 3D open-world development,
physics, WebView integration

Infrastructure: Docker, CI/CD, Ubuntu, Nginx, PM2, CDN, monitoring, production deployments
PROFESSIONAL EXPERIENCE
Independent Unity / Full-Stack Game Developer Jul 2026 - Present
Independent project
• Built a Unity mobile RPG architecture combining a procedural 3D open world, Node.js backend,
React WebView interface, and AI-generated player content.

OLEKSANDR KALINICHENKO • SENIOR FULL-STACK ENGINEER

• Developed a hex-grid world system with procedural terrain, environmental objects, physics-based
projectiles, spells, inventory mechanics, and character progression.
• Built a geographic data-processing pipeline for the game world and imported over 114.57 million
points of interest and map objects into MongoDB, including geometry and metadata used for
procedural placement and world generation.
• Structured geographic data into 20375 map regions/chunks for efficient loading and conversion into a
playable hex-based 3D environment.
• Designed and created a custom LoRA training dataset of 1,200 curated images, covering 100 races,
100 classes, and 100 professions, with four reference images per category.
• Trained and fine-tuned a custom LoRA model for generating stylized game characters from
user-uploaded photos while preserving recognizable facial features.
• Built an AI pipeline combining OpenAI vision models and the LoRA model: the system analyzes the
user’s photo, generates a structured visual description, and creates a race-, class-, and
profession-specific prompt for character generation.
• Built the complete UI and backend flow for photo upload, character configuration, prompt generation,
image generation, result processing, storage, and delivery to the Unity client.
Full-Stack JavaScript & AI / Computer Vision Engineer Sep 2025 - Jun 2026
Fitofan
•Built tournament and league management systems for 3 sports, including automated bracket
generation and end-to-end competition workflows supporting 10+ tournament formats and rulesets,
such as round-robin, single elimination, double elimination, and group stages.
• Developed full-stack flows for managing user accounts, organizations, teams, rosters, roles, and
competition participation across a Node.js/NestJS backend and React frontend.
• Built an IBM Watson-based LLM assistant with RAG over internal platform knowledge, enabling users
to create and configure tournaments, leagues, competitions, teams, and related entities through
natural-language conversations, with automated clarification, validation, and backend action
execution.
•Developed a taekwondo poomsae pose-tracking and temporal action-recognition system using
approximately 1.5 TB of images and annotated JSON data, including 600K+ labeled images,
300+hours of 60 FPS video, 700K annotated movement samples, 40+ movement classes, 33 body
keypoints, and footage captured from 8 camera directions. Implemented pose estimation,
skeleton-sequence analysis, movement classification, trajectory comparison, and technique
assessment against reference poses.
• Built a human-in-the-loop video auto-annotation and model-training platform that automatically splits
uploaded videos into movement segments, performs pose estimation, visualizes keypoints and
skeletons frame by frame, and allows reviewers to correct annotations before retraining or fine-tuning
models.
• Developed a basketball analytics prototype using open-source detection and multi-object tracking
models for player and ball tracking, persistent identities, movement trajectories, court positioning,
and team classification based on jersey colors using a custom Roboflow-trained model.

OLEKSANDR KALINICHENKO • SENIOR FULL-STACK ENGINEER

• Independently designed the UX, product architecture, and initial implementation of a sports-club
CRM covering client management, memberships, subscriptions, attendance, training-slot planning,
homework, coach journals, and AI-driven attendance and retention insights.

PROFESSIONAL EXPERIENCE - CONTINUED
Backend JavaScript Developer -> Team Lead / Acting CTO Feb 2021 - Aug 2025

• Progressed from Backend Developer to Team Lead / Acting CTO and managed a cross-functional
team of 11 engineers and designers, covering hiring, onboarding, planning, estimation, architecture,
code reviews, releases, performance management, and production support.
• Delivered 25+ commercial web and mobile products, owning the complete lifecycle from client
acquisition and requirements discovery to UX planning, backend architecture, team formation,
implementation, infrastructure setup, publication, and post-release support.
• Worked directly with clients and designers to transform business requirements into product flows and
scalable technical solutions, defining backend architecture, data models, integrations, security,
infrastructure, and development plans before implementation.
• Architected and delivered Resonance, a low-frequency audio platform for a Japanese clinic network,
with CDN-based media delivery, multi-layer caching, subscriptions, OTA updates, support for older
Android devices, and infrastructure designed for peaks of up to 10K requests per second.
• Built an integrated mobile application, CRM, and warehouse-terminal ecosystem for Logistics,
supporting approximately 100K shipments per month, including transport orders, warehouse
operations, shipment statuses, employee tasks, document workflows, customer management, and
real-time synchronization.
• Developed a real-time video analytics platform with object detection and multi-object tracking across
30+ behavioral and spatial indicators, including line crossing, zone entry and exit, barrier passage,
vehicle and license-plate tracking, people counting, dwell-time analysis, movement trajectories,
occupancy monitoring, heatmaps, and automated event alerts.
Full-Stack JavaScript Developer Mar 2020 - Feb 2021
Grootsoft LTD
• Contributed to the development of a cryptocurrency exchange, implementing backend functionality,
integrations, and supporting services using Node.js and Express.
• Built an automated bidding system for Copart and IAAI vehicle auctions using Puppeteer, including
authentication, lot monitoring, bid placement, retries, validation, notifications, and anti-bot handling; the
system executed around 200 bids per night.
• Developed backend services for sushi delivery and similar food-ordering platforms, covering menus,
carts, orders, delivery workflows, customer data, admin operations, and third-party integrations.

EDUCATION
Master's degree - Computer Science Teacher | Kharkiv Humanitarian-Pedagogical Academy
Bachelor's degree - Cybersecurity, Major 125 | Kharkiv National University of Radio Electronics
Junior Specialist - Software Engineering, Major 121 | Kharkiv Patent and Computer College
LANGUAGES
Ukrainian - Native | Russian - Fluent | English - B2
OLEKSANDR KALINICHENKO • SENIOR FULL-STACK ENGINEER