Oleksii Ветеран

Oleksii Perkin
RUBY ON RAILS BACKEND / FULL-STACK DEVELOPER
Kyiv, Ukraine | [відкрити контакти](див. вище в блоці «контактна інформація») | Telegram: t.me/operkin | [відкрити контакти](див. вище в блоці «контактна інформація») | [відкрити контакти](див. вище в блоці «контактна інформація»)

PROFESSIONAL SUMMARY
Backend-focused engineer with 6 years of commercial software development experience, including 4+ years with Ruby on Rails.
Strong background in fintech and crypto products, REST APIs, wallet and payment flows, authentication, third-party integrations,
React, RSpec, and production support. Recent experience also includes building an internal AI-assisted software delivery workflow
from scratch. Ukrainian war veteran. Open to remote, hybrid, and office work in Kyiv.

CORE STACK
Languages & Frameworks: Ruby, Ruby on Rails, React, JavaScript, ActiveRecord | Data & Infrastructure: PostgreSQL, Redis, Docker |
APIs & Auth: REST APIs, JWT, Google SSO, third-party integrations | Testing & Tools: RSpec, FactoryBot, VCR, Git, Bitbucket, Jira,
Postman | AI & Automation: Claude, Codex, Google Antigravity, OpenClaw, AI agents

PROFESSIONAL EXPERIENCE
Glendeal / B2B marketplace
Full-Stack Developer | AI Development Automation | May 2025 - Sep 2026
• Designed and built from scratch an internal AI-driven software delivery service connecting Telegram/Jira task intake to implementation,
automated tests, browser checks, AI review, approvals, CI and deployment.
• Orchestrated Claude, Codex and Antigravity agents and built task-state, retry/recovery, review-gate, and evidence-retention logic.
• Earlier in the role, contributed to marketplace features in Python/Django + React, including verification, SMS/email integrations and
webhooks.
CodeIn Inc. / Crypto exchange
Backend Ruby on Rails Developer | Project: Ucrypt | Apr 2023 - May 2025
• Built backend features for wallet, deposit, withdrawal, authentication, and provider-integration flows in a crypto exchange.
• Integrated Solana and Arbitrum into exchange wallet and asset flows; built cold-wallet workflows with multisig support through Safe
integration.
• Implemented deposit and withdrawal logic with blockchain and exchange fee calculation for core wallet operations.
• Contributed to Rails 4 to Rails 5 migration and to moving monolithic flows toward API endpoints used by a mobile app.
• Built JWT-based authentication and registration APIs; integrated Quicko and GEO Pay; added notifications through email, Telegram, and
admin logging.
• Performed code reviews and contributed to technical decisions with the tech lead.
CyberCraft Inc.
Full-Stack Ruby on Rails / React Developer; Backend Ruby on Rails Developer | Oct 2020 - Jan 2023
• Chime Financial Inc.: wrote and maintained 1,000+ RSpec tests across Ruby microservices, implemented JWT-based API
authentication, and built React-based QA tooling used by testers.
• Modularity: implemented payment-service integrations and React UI blocks for purchase and payment workflows; wrote end-to-end
RSpec tests and fixed production issues.
• AchWho / Core One for Labs: designed initial database schema and product workflows, built registration/authentication flows including
Google SSO and Google Maps API verification, and maintained backend features, tests, and documentation in production systems.

LANGUAGES
English: Upper-Intermediate (B2) | Ukrainian: Native

EDUCATION
Lviv State University of Physical Culture | Bachelor's Degree in Management (in progress, part-time)

ADDITIONAL TRAINING
Cryptology, Kyiv | Supercharged + Workshop | Dec 2024 - Jan 2026. Completed structured training in cryptocurrency markets,
trading workflows, market analysis, and risk management, strengthening domain knowledge for crypto-focused products.