Roman

ROMAN HORISHNYI
Lviv, Ukraine (GMT+3) | [відкрити контакти](див. вище в блоці «контактна інформація») | [відкрити контакти](див. вище в блоці «контактна інформація»)
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SUMMARY
Backend engineer fluent in Python and Go.​
I build and scale high‑load systems—squeezing 1.5kk + req/s through REST / gRPC APIs, hardening
them with OAuth2, PCI‑grade payments, and blockchain oracles, and shipping via Docker‑K8s CI/CD
with 99.99% uptime.
My migrations and tuning cut outages 30% and response times 25%, turning complex EdTech, SaaS,
and Web3 ideas into reliable, revenue‑driving products.

TECHNICAL SKILLS
Programming Languages: Golang, basic C/C++/Rust understanding
Databases: PostgreSQL, CockroachDB, MySQL, MongoDB, Redis, Dragonfly, Cassandra, ScyllaDB,
Clickhouse
Frameworks: React
Tools: gRPC, NATS, Kafka, RabbitMQ, AWS (EC2, DynamoDB, S3, SQS, SES), Docker, Kubernetes,
CI/CD, Prometheus + Grafana

WORK EXPERIENCE

Software Engineer (Contract for 6m) ​ ​ ​ ​ ​ 06/2024 - 01/2025
ContentQuo | Tallin, Estonia

●​ Contributed to the "Plan" microservice for translation evaluations, helping win Spotify as a client.
●​ Led integration of Smartcat TMS — TikTok's top requirement — enabling automated translation
data importsand.
●​ Built and maintained the Market Reach service to improve platform usage insights.
●​ Boosted performance by cutting redundant API calls and optimizing SQL queries time by 25%.

Software Engineer ​ ​ ​ ​ ​ ​ ​ 01/2024 - 06/2025
Overdone | Kyiv/Odessa, Ukraine

●​ Designed and implemented a custom Oracle service for secure off-chain data fetching,
significantly enhancing prediction trust and accuracy.
●​ Built and maintained the Telegram bot backend for real-time updates, driving user
engagement.
●​ Architected the platform's database (ERD) and REST API, streamlining front-end integration
and boosting development efficiency.
●​ Collaborated cross-functionally to define technical requirements and continuously improved
system scalability and performance through robust backend architecture.
Software Engineer ​ ​ ​ ​ ​ ​ ​ 01/2023 - 01/2024
Speetail | Las Vegas, USA

●​ Designed and delivered key Go microservices, directly contributing to a 30% reduction in
downtime and substantial reliability improvements.
●​ Streamlined development cycles through the implementation of automated testing and
deployment pipelines.
●​ Integrated critical third-party services (payments, logistics) and mentored junior developers,
fostering robust development practices and optimizing overall system performance.

Software Engineer ​ ​ ​ ​ ​ ​ ​ 01/2021 - 01/2023
Creatly LMS | Kyiv, Ukraine

●​ Architected and implemented high-performance REST APIs, significantly improving platform
communication, developer productivity, and system reliability.
●​ Delivered the Dynamic Students Cabinet and Flexible Courses API, empowering learners with
intuitive progress management and streamlining course creation for content creators.
●​ Crucial in integrating secure payment systems and introducing innovative features that
enhanced user experience and learning outcomes, driving the platform's success

RELEVANT EXPERIENCE AND PROJECTS

●​ Developed lightweight, expressive error handling library 123 that provides error codes, context,
and a fluent builder API.
●​ Developed a caching library with TTL expiration and a built-in cleanup worker 123