Full-Stack Developer
Address: Khmelnytskyi, Ukraine
Full-Stack Developer with 7+ years of experience building scalable backend systems, APIs and web apps. Skilled in Ruby on Rails, Node.js, Vue, Go, and DevOps tools like Kubernetes and Flux, Terrafrom. Delivered blockchain platforms, AI-driven EdTech, and search apps using Elasticsearch.
Languages:
Ruby, JavaScript/TypeScript, Go, Python
Frameworks & Libraries:
Ruby on Rails, Express.js, Vue, Nuxt, Stimulus
Backend & APIs:
REST API, WebSockets, Sidekiq, BullMQ
Databases & Storage:
PostgreSQL, MySQL, MongoDB, Redis, Elasticsearch, BigQuery
DevOps & Infrastructure:
Docker, Kubernetes, FluxCD, GitHub Actions, Terraform, Ansible, SOPS, Helm, Kustomize
Cloud Platforms:
Digital Ocean, Heroku, Cloudflare, AWS ECS, Google Cloud (GKE)
Testing:
RSpec, Minitest
Monitoring:
OpenTelemetry, Grafana Stack
3rd-party & SaaS:
OpenAI API, ChatGPT API, DataDog, New Relic, Logtail, Facebook API, Instagram API, WhatsApp API
Other:
Chrome Extensions, MCP (Model Context Protocol), A2A
- Designed and deployed a production-ready GitOps setup using FluxCD on Kubernetes
- Provisioned infrastructure with Terraform (GKE)
- Built custom Helm charts for application deployment and managed secrets via SOPS
- Configured observability stack: Prometheus, Grafana, Loki with dashboards for cluster health, app metrics, and alerts
- Enabled automatic image updates and progressive delivery with Kustomize overlays
- Used GitHub Actions for Terraform workflows and CI/CD validation pipelines
- Built custom Kubernetes operator using Kubebuilder framework for automated MCP server lifecycle management
- Implemented custom resource definitions (CRDs) and controllers for server provisioning, scaling, and health monitoring
- Developed reconciliation logic with event-driven architecture for maintaining desired server state
- Created A2A (Agent-to-Agent) agents using Custom Resources as part of demonstration scenarios
- Integrated with Kubernetes RBAC and service mesh for secure inter-service communication
Stack: Go, Python, Kubebuilder, Kubernetes APIs, Custom Resources
Ruby on Rails/Vue2 Fullstasck developer
- Customized and extended a messaging and support platform with inboxes, real-time chat, and agent workflows
- Developed backend logic for ticketing, conversation assignment, and customer metadata management
- Built and styled front-end views using TailwindCSS, and server-rendered components
- Integrated APIs for third-party channels and notifications (Facebok, Instagram, Whatsapp)
Stack: Ruby on Rails, PostgreSQL, Redis, Stimulus, TailwindCSS, Webpacker
DevOps Engineer / Developer
- Migrated Ruby on Rails app from Heroku to Digital Ocean App Platform, reducing hosting costs by 40%
- Refactored Rails application to follow 12-factor app principles for better scalability and maintainability
- Implemented Docker containerization and GitHub Actions CI/CD pipelines for automated deployments
- Set up preview environments for feature branches, enabling faster QA cycles and stakeholder reviews
- Updated team development workflow with automated testing, code quality checks, and deployment gates
- Integrated SaaS monitoring solutions like DataDog and Logtail for application data tracking
- Optimized build processes and deployment strategies, reducing deployment time by 25%
- Maintained 99.9% uptime across all migrated services during transition period
Stack: Terraform, Docker, GitHub Actions, Digital Ocean, PostgreSQL, Ruby on Rails, Cloudflare
Node/Typescript Backend developer
- Developed secure, high-load blockchain sale flow with validation at multiple levels
- Built fail-safe Sidekiq workers for crypto transaction confirmation
- Achieved 99.99% uptime during sale period with >10K tx processed
- Tech: Express.js, MySQL, Redis, Sidekiq, REST API
Node/Typescript Backend developer
- Created backend API for blockchain explorer and data access
- Built sync services and webhooks for new blocks/events using bullmq
- Handled high-frequency write patterns with optimized indexing strategy
- Tech: Express.js, bullmq, Mongo, REST API
Backend developer
- Designed backend APIs and scheduling system for teacher availability
- Integrated ChatGPT for post-lesson summarization and suggestions
- Built upload/streaming system for class recordings and materials
- Reduced manual note creation by 80% via AI post-processing
- Tech: Ruby on Rails, PostgreSQL, Redis, REST API, Sidekiq, ChatGPT
Ruby on Rails Fullstasck developer
- Managed 2M+ Elastic documents with hourly reindex and caching
- Built Trie-based search engine supporting >50 RPS
- Enabled Cloudflare caching with <100ms TTFB globally
- Built async import/export and analytics workers
- Tech: Ruby on Rails, Elasticsearch, PostgreSQL, Redis, Heroku, Cloudflare, BigQuery
Ruby on Rails/Vue2 Fullstasck developer/Lead developer Golang Backend fro mobile API
- Maintained and optimized Golang and Python APIs for search & analytics
- Implemented caching strategies and moved SSR from Nuxt to Cloudflare, imporoved response times by 15% for p99
- Built Chrome extension for internal dictionary scraping
- Cut API latency by 30% via algorithm improvements
- Tech: Ruby on Rails, Go, Python, Nuxt, Cloudflare, Chrome Extension, AWS ECS
Ruby on Rails/Vue2 Fullstasck developer/Lead developer
- Designed a modular CMS engine to manage multiple content portals
- Added media upload, scraping via proxy server, and CSV import
- Used Trie structure for efficient search index
- Improved SEO performance by 40% after architecture changes
- Tech: Ruby on Rails, CarrierWave, Sidekiq, Vue, Stimulus, Elasticsearch, Node.js, Heroku
- Ruby on Rails/Vue2 Fullstasck developer *
- Developed and maintained a CRM for managing shipments and deliveries
- Optimized complex SQL queries and background processing to improve system throughput
- Created internal admin tools for logistics team automation
- Achieved 2× faster average response time on key dashboards
- Tech: Ruby on Rails, PostgreSQL, Redis, Sidekiq, Kafka
- Front-end lead & backend contributor in a small team
- Solved real-time UI performance bottlenecks using WebSockets
- Refactored API layer to reduce memory load under scale
- Tech: React, Redux, Thunk, WebSockets, Ruby on Rails, Sidekiq
- Developed Vue.js app for interactive drag-n-drop menu building
- Handled WebSocket integrations for real-time edits
- Implemented versioning logic for menu publishing
- Tech: Vue, Ruby on Rails, WebSockets
- Created dynamic analytics dashboard with filters and graphs
- Connected Rails backend to Elastic data source
- Reduced average load time by ~60% through data batching
- Tech: React, Elasticsearch, Ruby on Rails
- Delivered Magento-based online stores with integrated payment systems
- Created plugins for WordPress and other PHP CMSs
- Transitioned some clients to Ruby on Rails for better maintainability
- Tech: Magento, PHP, Ruby on Rails
- DevOps and Kubernetes. Practical Intensive+ (prometheus.org.ua) — 2025 April - June
Master's in Computer Engineering
Khmelnytskyi National University — 2014 – 2019