Олег

Oleh Deneka
Full Stack Developer
Lviv, Ukraine · Open to Remote
Email: [відкрити контакти](див. вище в блоці «контактна інформація»)
LinkedIn: [відкрити контакти](див. вище в блоці «контактна інформація»)

SUMMARY

Full Stack Developer with 6+ years of experience building and scaling fintech products across mobile and
web. Experienced in leading a team of 5 developers on a white-label banking platform serving 10+ tenants,
thousands of end-users, and 15 independently deployed microservices. Deep hands-on expertise in React
Native, React, Node.js, and AWS serverless — from first commit to production, on every layer of the stack.

SKILLS

Mobile: React Native, Expo, React Native Reanimated, Deep Linking, Push Notifications, App Store Deployment,
Performance Optimization
Front-End: React, TypeScript, JavaScript, Next.js, React Query, Redux, Redux-Saga, GraphQL, Context API,
HTML, CSS
Back-End: Node.js, TypeScript, AWS SAM, Serverless Framework, Firebase FCM, Microservices, REST API,
Webhooks
AWS: Lambda, DynamoDB, Cognito, CloudFormation, S3, SQS, EventBridge, SES, API Gateway, Amplify
Databases: DynamoDB, PostgreSQL, Elasticsearch
DevOps & Tools: Git, GitHub Actions, CI/CD, Terraform, Docker, Figma, Postman, Xcode, Android Studio
AI: OpenAI APIs (text generation, function calling, assistants)
Leadership: Team Leadership, Code Review, Architecture Design, Hiring, Mentoring

EXPERIENCE

Tech Lead & Full Stack Developer
White-Label Banking Platform · Multi-Tenant SaaS | Feb 2023 — Present
Architected a multi-tenant configuration system that reduced new tenant onboarding from weeks to days,
enabling the platform to scale to 10+ active tenants from a single codebase
Built a full card services module end-to-end — card issuing, loading, and real-time data synchronization with
an external provider — engineering idempotent API handling to guarantee reliability over an unstable third-
party integration
Designed and implemented Transaction MFA across backend (Node.js/DynamoDB), web (React), and mobile
(React Native) — supporting push notifications via Firebase, biometry, SMS, and TOTP, fully configurable per
tenant
Developed a foreign exchange feature with a configurable admin panel for managing currency pairs, rate
providers, and exchange providers — each independently selectable per tenant
Promoted to Tech Lead; responsible for all architecture decisions, code reviews, hiring, and mentoring across
the engineering team
Managed team of 5 developers — made hiring decisions, onboarded new developers, and maintained code
standards across 15 microservices with frequent production deployments
Oversaw deployment infrastructure using Terraform and AWS SAM, streamlining CI/CD flows for multi-tenant
releases
Redesigned front-end deployment pipeline with GitHub Actions — replaced a manual multi-branch process
that took hours with a single-branch automated flow, reducing deployment time to minutes
Technologies: React Native, React, TypeScript, Node.js, DynamoDB, PostgreSQL, AWS SAM, Terraform, Firebase,
Lambda, API Gateway, Cognito

Full Stack Developer
Stock Tracking Mobile & Backend Application | Jul 2022 — Feb 2023
Built an end-to-end stock tracking application — mobile client and complete serverless backend — enabling
users to search stocks, create price-tracking orders, and attach custom data including images, files, and
video
Implemented infinite-scroll feeds with mixed media (images, YouTube embeds, charts) and deep-linked share
functionality that navigated users directly to specific asset detail screens
Developed a real-time leaderboard displaying top performers across daily, weekly, and monthly intervals, plus
user profiles with accolades and performance metrics
Integrated OpenAI APIs (text generation, function calling, assistants) to power intelligent features within the
application
Designed the backend with Serverless Framework, DynamoDB, Elasticsearch, and Lambda — handling auth
via AWS Cognito and Amplify
Technologies: React Native, React Query, Context API, React Native Reanimated, Skia, FlashList, Serverless
Framework, DynamoDB, Elasticsearch, Lambda, OpenAI, Puppeteer

Full Stack Developer
Medical Center Platform | May 2022 — Jul 2022
Automated PDF certificate generation and email distribution for a large user base, eliminating a manual
process that previously required significant staff time
Integrated Salesforce data pipelines — created Node.js webhooks to receive third-party events, persist data
to Salesforce, and surface it through low-code iframe components
Technologies: Vue.js, Node.js, Salesforce, Outlook API, Webhooks

React Native Developer
Fintech Mobile Application | Jan 2020 — May 2022
Served as the primary front-end developer on a fintech mobile app, owning the React Native codebase and
collaborating directly with the client to translate business problems into technical solutions
Implemented statistical graphs, advanced search, multi-language support, and fluid animations — optimized
performance across the entire application
Integrated AWS Amplify for data sync and authentication, and managed the full deployment lifecycle to both
the Apple App Store and Google Play Store
Technologies: TypeScript, React Native, Redux, Redux-Saga, AWS Amplify, REST API, Figma

React Native Developer
Mobile Banking Demo & Movie Selection App | Feb 2019 — Jan 2020
Built a demo mobile banking application from scratch — sign-up/login, identity verification with camera
integration, payments, transfers, and card creation — used in live sales negotiations to close deals
Implemented push notifications to simulate real-time banking interactions, directly contributing to successful
client acquisition pitches
Developed a movie selection app covering the full front-end with Redux-Saga state management, AWS
Cognito auth, animations, and end-to-end deployment
Technologies: React Native, Redux, Redux-Saga, AWS Amplify, AWS Cognito, REST API, Figma

EDUCATION

B.Sc. Computer Science
Lviv Polytechnic National University, 2018 — 2022

LANGUAGES

English — Advanced
Ukrainian — Native