Bohdan

[открыть контакты](см. выше в блоке «контактная информация») Bohdan-Pohranychnyi

Bohdan Pohranychnyi
Exp erienced Backend Developer with 4 years of experience in designing and building scalable, high-performance APIs (achieving response times between 150–250ms)
using Python, a range of frameworks, libraries, and custom-built solutions. Skilled in database design, data modeling, asynchronous programming, and deploying and
monitoring applications on servers. My apps efficiently interact with frontend applications, other internal/external backend services and event-driven systems for internal
communication between microservices. I take full ownership of projects and consistently deliver reliable, efficient, and maintainable systems. Additionally, my experience
include communicating in English with international teams.

• Python • astAPI
F • Flask • DRF • Tornado • L angChain • AWS S3/EC2/SES • MongoDB • PostgreSQL • Asyncio
• CI/CD • N ginx • D ocker • L inux • S entry • G raylog • G rafana • G radio
I was involved in developing and leading several projects across different industries, including fitness, gaming, healthcare, and chat/support bots. Due to confidentiality
agreements, I am unable to disclose full project details. Below, I highlight the most significant and valuable cases where my contributions had a major impact. Common
development tasks — such as basic API developing and standard backend work — are omitted.

Experience
B2B/B2C services with high-volume API interactions Aug 2021 – Present

Technologies: Python, MongoDB, PostgreSQL, Asyncio, Aiohttp, Tornado, Docker

Played a key role in transforming the B2B/B2C services by addressing the complexity of managing over 80 different API configurations. The existing solution was
cumbersome, requiring frequent server restarts for every configuration change, leading to inefficiencies, delays, and a significant slowdown in operational activity.

I proposed and developed a custom configuration management tool that automated the configuration process across various API environments. This tool, designed
for flexibility, enables the seamless management of API keys, flags, URLs and other configuration elements. The solution was approved and successfully
implemented, significantly reducing operational overhead and improving the management of different external APIs.


The legacy system struggled with inconsistent data handling and frequent failures, which resulted in significant operational challenges and inefficiencies. These
issues led to operational disruptions and considerable downtime, affecting team productivity.

I designed and implemented a new solution using cron jobs that optimized the handling of approximately 300K requests per day to external services. As a result,
operational issues were significantly reduced, leading to a 99% decrease in complaints from the operational team. The new system now consistently delivers
timely, accurate data, enhancing the overall reliability of the operations.


I designed and implemented a standardized data conversion layer to handle currency data across multiple systems. As the platform interacted with various external
systems and APIs, each requiring different data formats, the existing approach became increasingly difficult to maintain. Financial data required custom conversion
logic for each API, which led to fragmented and non-maintainable data handling across the system. This resulted in duplicated efforts and a growing complexity. To
resolve this, I created a centralized data conversion layer that unified the handling of currency data. This layer allowed easy configuration through customizable
settings, enabling consistent data conversion and calculations across all interactions with external APIs. This approach improved maintainability and reduce
complexity, enabling easier updates and scale.

Designed and implemented a configurable request management layer (utility), enabling controlled high-volume API calls (outgoing) with flexible settings (per-
second rate limits, concurrent connections) and functionality to dynamically adjust configurations on the fly, which significantly accelerated future feature
integration and keep code cleaner and maintainable.

High-concurrency optimization behind a Telegram bot Nov 2024 – Feb 2025

Technologies: Python, Asyncio, Aiohttp, Aiogram, MongoDB

Redesigned and optimized backend service behind a Telegram bot, responsible for aggregating large-scale data ( ~1M requests) from multiple third-party servers.

Fixed critical performance bottlenecks: the original system suffered from frequent request blocking and inefficient concurrency management, resulting in an
estimated runtime of 6–8 days.

Implemented dynamic throttling, intelligent batching, advanced retry strategies, and enhanced asynchronous handling — reduced total execution time to
approximately 10 hours.

Implemented a dynamic internal monitoring and control system, featuring configurable parameters and real-time reporting on progress and request statuses,
significantly improving operational transparency and control.

L ightweight HR system Aug 2023 – Oct 2023 (2025)

Technologies: Python, FastAPI, LangChain, MongoDB, Docker, AWS Services, Gradio

Developed the entire backend infrastructure for a lightweight HR management system.

Containerized the backend services using Docker, enabling consistent deployments across development and production systems.

Set up and managed AWS EC2 instance, handled DNS configurations, and configured Nginx.

Built and maintained a fully automated CI/CD pipeline with G itHub Actions, streamlining testing, builds, and deployments to significantly accelerate release cycles

and reduce downtime.

Integrated AWS SES and Twilio service for automated and reliable email notifications, ensuring scalable communication workflows with end-users.

Developed an AI-powered email management extension (2025 year) using the LangChain framework, enabling automated creation and delivery of emails.
Additionally, built a lightweight Gradio frontend to quickly expose API capabilities, allowing managers to faster create and send personalized emails.

M entoring
Additionally, I have experience working with interns and junior developers across several projects, providing technical onboarding, guidance, and code reviews to
ensure code quality and support professional growth within the team.
Ukrainian С2 • E nglish B 2