Владислав

Vladyslav Hrynkiv
Junior Python / Django Backend Developer
Odesa, Ukraine (open to remote) | [open contact info](look above in the "contact info" section) | [open contact info](look above in the "contact info" section)
github.com/pikaOpika | [open contact info](look above in the "contact info" section)

SUMMARY
Backend developer with an Applied Mathematics degree and hands-on IT support experience, now focused on Python and
Django. Built several REST APIs end to end: JWT authentication, PostgreSQL with database-level integrity constraints, Celery
background jobs, Docker Compose environments, tests and OpenAPI documentation. Looking for a junior backend role,
on-site in Odesa or fully remote.
TECHNICAL SKILLS
• Languages: Python, SQL
• Frameworks: Django, Django REST Framework, aiogram
• Databases: PostgreSQL, SQLite — ORM optimisation (select_related, prefetch_related, annotate/aggregate, F and Q),
constraints, transactions and isolation, indexing, normalisation
• API: JWT (SimpleJWT) with refresh rotation and blacklisting, custom permissions, filtering, pagination, nested routes,
drf-spectacular (OpenAPI / Swagger)
• Async & tasks: Celery, Celery Beat, Redis, asyncio
• Infrastructure: Docker, Docker Compose (multi-service with healthchecks), environment-based configuration, Git / GitHub,
Postman
• Testing: Django TestCase, DRF APITestCase — permissions, business rules, background tasks
PROJECTS
Theatre Booking API
Django, DRF, PostgreSQL, JWT, Docker Compose
• Seat booking with integrity enforced in the database: a unique constraint on (row, seat, performance) plus check constraints,
cross-table rules in clean(), and reservation creation wrapped in transaction.atomic().
• Closed the race condition serializer validation cannot catch by converting IntegrityError into a clean 400 response.
• Cut list endpoints from 7 queries to 1–3 with select_related / prefetch_related; computed available seats with annotate and F
expressions.
• Added query-parameter filtering, custom pagination with a max page size, JWT auth with rotation and blacklisting, an
OpenAPI schema and model / API tests.
Social Media API
Django, DRF, PostgreSQL, Celery, Redis, Docker Compose
• Custom user model with email login and a self-referential many-to-many follow graph; posts, likes, on-the-fly hashtags,
comments on nested routes and a feed built from followed authors.
• Scheduled publishing via Celery Beat: a periodic task publishes due posts with one bulk update, keeping it idempotent and
all state in the database.
• Five-service Docker Compose stack (db, redis, app, worker, beat) with healthchecks; 13 tests covering permissions, visibility
and the publishing task.
Library Service API — in progress
Django, DRF, Celery, Stripe, Telegram Bot API
• Borrowings with overdue fines, Stripe payments in test mode, Telegram notifications and a daily Celery job for overdue
checks.
Telegram Broadcast Bot
Python, aiogram 3.x, SMTP
• FSM-based admin workflow with inline menus, media-group broadcasting via copy_messages, and email delivery run
through asyncio.to_thread to keep the blocking SMTP client off the event loop.
EXPERIENCE
IT Support Specialist
Municipal Service of Communal Property of the Odesa City Council, IT Department — Odesa | February 2025 – Present
• First-line support for staff: diagnosed and resolved day-to-day hardware and software issues across computers and office
equipment.
• Maintained the hardware fleet: component-level repairs, preventive maintenance, printer and MFP consumables.
• Basic LAN troubleshooting: localised and fixed connectivity failures (cabling, routers, endpoint configuration).
EDUCATION
• Mate Academy — Python Developer program (Django, DRF) — in progress
• Odesa I. I. Mechnikov National University — B.Sc. in Applied Mathematics (2023), M.Sc. in Economics (2024)
LANGUAGES
Ukrainian — native | Russian — native | English — B1