Kyrylo

KYRYLO KRYZHANOVSKYI
Python Backend Engineer
[open contact info](look above in the "contact info" section) • [open contact info](look above in the "contact info" section) • github.com/kryzhanovskyik • [open contact info](look above in the "contact info" section) •
Kosice, Slovakia • Open to Remote

PROFESSIONAL SUMMARY

Python backend engineer who builds production-ready APIs and data systems using FastAPI, PostgreSQL, and
Docker. For Codeess, he designed an engine that translates node-based visual logic into executable Python
code — a non-trivial system architecture problem that most engineers encounter much later in their careers. His
track record on shipped projects includes a 40% reduction in API response time through async query optimization
and 80%+ test coverage maintained across unit and integration layers.

TECHNICAL SKILLS

Languages: Python (primary), JavaScript / TypeScript, SQL
Frameworks & Libraries: FastAPI, SQLAlchemy 2.0, Pydantic, Django, Flask, Next.js (React), httpx, Celery
Databases & Caching: PostgreSQL (query optimization, migrations, schema design), Redis, MongoDB, SQLite
DevOps & Tooling: Docker, Docker Compose, Git, GitLab CI/CD, AWS (EC2, S3), GCP, Pytest, Sentry

ENGINEERING PROJECTS

Codeess — Visual Logic-to-Code Platform | github.com/kryzhanovskyik/codeess Feb 2026 – Present
Stack: FastAPI, PostgreSQL, SQLAlchemy 2.0, Next.js, TypeScript, TailwindCSS, Docker
• Built a core translation engine that parses node-based graphical logic into executable Python code, enabling
domain experts to define backend workflows visually.
• Designed a modular FastAPI backend with clearly separated layers (routers → services → repositories),
making it straightforward to add new node types without touching existing logic.
• Engineered a versioned PostgreSQL schema to store and diff complex node graphs, supporting rollback and
configuration history for user workflows.
• Developed the frontend visual editor in Next.js and TypeScript with real-time node state synchronization to
the backend, keeping UI and API state consistent under concurrent edits.
• Containerized the full stack with Docker Compose, reducing environment setup to a single command for
local development and deployment.

Hotel Management & Booking System | github.com/kryzhanovskyik/hotel-api Feb 2026
Stack: FastAPI, PostgreSQL, SQLAlchemy 2.0 (async), Redis, JWT, Pytest, Docker
• Architected a layered backend (services / repositories) that decouples business logic from data access,
making the system easy to test in isolation and extend with new booking rules.
• Reduced API response times by 40% under concurrent load by migrating all database queries to
SQLAlchemy 2.0 async sessions, eliminating blocking I/O on critical booking endpoints.
• Implemented JWT-based authentication with granular, role-scoped permissions (admin, staff, guest),
preventing unauthorized access to reservation and pricing data.
• Achieved 80%+ code coverage with a Pytest suite covering unit and integration layers, catching edge cases
in booking conflict detection before they reached production.
 • Stored JWT session data in Redis with TTL-based expiry aligned to token lifetime, removing redundant
database lookups on every authenticated request and keeping auth overhead constant regardless of active
session count.

EDUCATION

BSc in Computer Science • Pavol Jozef Šafárik University, Košice, Slovakia (Expected 2028)
Core modules: Algorithms & Data Structures, Software Engineering Principles, Computer Networks
Python Pro Advance • Logika School (2025)
Focus: Python Core, Flask, FastAPI, Django, Backend Engineering Patterns

LANGUAGES

English — Fluent • Ukrainian — Native • Russian — Fluent • Slovak — Pre-Intermediate