Денис

CKyiv,
ontact
Ukraine
[open contact info](look above in the "contact info" section)
@Hepizawr – preferred Denys Diachenko
[open contact info](look above in the "contact info" section) MIDDLE Full-Stack

[open contact info](look above in the "contact info" section) Developer
github.com/Hepizawr

TECH SKILLS About
Backend Full-Stack Software Developer with over 2+ years
Pytho n
of commercial experience building and scaling
Django, DRF, Fastapi, Flask, comprehensive end-to-end products.

HTTPX, aiohttp, sqlalchemy,
Selenium, PyTest, NumPy, With a proven track record of reducing system
pandas, Pillow, Telethon complexity and resolving deep architectural
Frontend bottlenecks, I deliver scalable and production-
H TML, CSS
ready applications. I actively adopt effective
JavaScript, TypeScript
engineering practices to maximize operational
REACT, NEXT.js efficiency. Whether designing reliable data
structures, architecting resilient APIs, or building
Database strict, functional frontends, I provide companies
S QL
with high-quality technical solutions that are built
POstgresql, MYSQL, MSSQL to last.
No SQL

MongoDB
Tools
D ocker
G it

GitHub, Gitlab

Actions, CICD
A I-assistants

claude code, cursor, CODEX

Rules, commands, skills,
MCP, hooks
Operating Systems
windows
L inux

Additional

Education Education Languages
Master | Sep, 2025 - Jun, 2027 apr, 2024 - may, 2024 Ukrainian - Native

Software engineering,
Software Development Russian - Native

Taras Shevchenko National
Lifecycle, University of English - Intermediate (b1)

University of Kyiv Minnesota Czech - Pre-Intermediate (A2)
Bachelor | Sep, 2021 - Jun, 2025 oct, 2023 - nov, 2023
Software engineering,
Build Website with HTML,
Taras Shevchenko National
JavaScript, AngularJS, and
University of Kyiv React, Board Infinity
FEB, 2023 - Mar, 2023
Continuous Integration and
ContinuousDelivery (CI/CD),
IBM

Experience
full-Stack developer

Web Design Sun | sep, 2025 - Present
D EVELOPED AND SCALED A COMPREHENSIVE WEB PLATFORM FOR AI TEXT DETECTION AND HUMANIZATION,
ACTIVELY CONTRIBUTING TO THE BACKEND, FRONTEND, AND BROWSER EXTENSIONS USING DJANGO,
NODE. JS, POSTGRESQL, AND AWS.
OPTIMI ZED BACKEND PERFORMANCE AND DATABASE INTERACTIONS AT THE DJANGO ORM LEVEL,
RESOLVING N+1 QUERY ISSUES AND REDUCING LOAD TIMES FOR CORE APIS AND THE ADMIN PANEL.

A RCHITECTED AND DEBUGGED COMPLEX THIRD-PARTY INTEGRATIONS, INCLUDING STRIPE PAYMENT
PROCESSING (ENSURING ROBUST WEBHOOK ERROR HANDLING AND IDEMPOTENCY) AND LMS PLATFORMS
(MOODLE, CANVA).

R ESOLVED CRITICAL DATA LOSS INCIDENTS BY ANALYZING SYSTEM FAILURES AND SUCCESSFULLY
RECOVERING AND IMPORTING MISSING STATISTICAL DATA INTO GOOGLE ANALYTICS AND CUSTOMER.IO.

MA NAGED THE TECHNICAL INTEGRATION OF NEWLY ACQUIRED EXTERNAL SERVICES INTO THE COMPANY'S
ECOSYSTEM, ENSURING SEAMLESS DATA FLOW AND ARCHITECTURAL CONSISTENCY.
CO NDUCTED COMPREHENSIVE CODE REVIEWS FOR DEVELOPERS OF ALL SENIORITY LEVELS, ONBOARDED
NEW TEAM MEMBERS, AND COLLABORATED CLOSELY WITH QA, DEVOPS, AND BAS IN A STRICT AGILE/SCRUM
ENVIRONMENT.
full-Stack developer

HUAWEI ukraine | dec, 2024 - jun, 2025
F ully re-engineered an internal research aggregation platform, reducing backend
codebase complexity by 40% and improving API response time by 25% through optimized use
of Python, Flask, SQLAlchemy, Requests, ldap3, Pydantic, and MySQL.
Designed and implemented a robust server-side structure from scratch, adhering strictly to
SOLID, KISS, DRY, and YAGNI principles, substantially improving system maintainability and
performance.

Designed and implemented a user-friendly administrative panel from concept to launch,
increasing UX satisfaction among internal users by over 2 times according to internal
surveys, with interactive frontend functionality developed using JavaScript.

Collaborated closely with the team to define project requirements, ensuring alignment and
efficient integration between client-side desktop application and backend infrastructure.

python developer

Ohara media | may, 2024 - oct, 2024
Developed and maintained an internal product for automating processes in Telegram based
on Python, Telethon, SQLAlchemy and PostgreSQL.

Optimized the project: reduced code by 30%, increased performance by 15%, improved code
readability and stability.

Participated in the development of a similar tool for WhatsApp using Selenium, solving
complex chat interaction problems.

Interacted with system administrators to customize multi-profile browser launcher by
writing a script to automate profiles in Mozilla Firefox.
python developer

LoyaltyAI | jun, 2024 - jul, 2024
Participated in developing an electronic receipt system using Python and Django for
Universal Bank (Monobank).

Rapidly adapted to complex financial logic and comprehensive documentation, quickly
taking responsibility for essential project tasks.

Developed automated tests covering approximately 10% of the system's functionality using
Django's built-in testing framework and PyTest, significantly enhancing code quality and
reliability.

Collaborated closely with experienced developers, utilizing Docker and GitHub for
infrastructure management and version control, gaining valuable insights into DevOps and
CI/CD practices.