Oleg C. — Senior Full-Stack Engineer, Lead

Bidel (Fiat Exchange Platform) - Full-Stack Developer, Tech Lead

Duration: Dec 2024 – Present

Technologies: NestJS, PostgreSQL, RabbitMQ, Redis, AWS, Datadog

About the project: Fiat exchange platform with microservice, event-driven architecture.

Responsibilities:

• Designed and led development of the platform architecture
• Built modular integrations for KYC, Twilio (SMS and conference calls), payment processing, exchange rate services, and analytics
• Implemented system monitoring, rate limiting, WAF, and Redis-based caching and security layers

PeerPe (P2P Fiat Application) - Backend Team Lead

Duration: Jan 2024 – Oct 2025

Technologies: NestJS, PostgreSQL, AWS (ELB, RDS, SQS), Redis

About the project: P2P fiat platform enabling peer-to-peer transactions.

Responsibilities:

• Led a backend team of three developers to build the platform from scratch
• Designed and implemented the full order lifecycle, including dispute resolution and auto-cancellation logic
• Developed customer support system and real-time chat functionality using WebSockets

TaskPulse (Task Management System) - Back-End Developer

Duration: Mar 2024 – Mar 2025

Technologies: NestJS, PostgreSQL, Redis, Azure, OpenAI

About the project: Task management and productivity platform with integrated email and AI features.

Responsibilities:

• Built the full backend for the platform
• Developed Pomodoro tracker with real-time WebSockets
• Integrated Gmail/Outlook APIs for unified inbox feature
• Implemented database encryption for sensitive data
• Integrated OpenAI with strictly typed responses

Luminex (IoT Projector Management) - Backend Team Lead

Duration: Apr 2024 – Jul 2024

Technologies: NestJS, MongoDB, PostgreSQL, Redis

About the project: IoT-based projector system management platform.

Responsibilities:

• Led a backend team of 2–3 developers
• Designed CRM and client application architecture
• Integrated payment systems and implemented subscription and appointment booking workflows

Firbo IO (Developer Productivity Analytics) - Backend Lead

Duration: Feb 2023 – Present

Technologies: NestJS, PostgreSQL, GCP, Redis

About the project: Platform that integrates with developer tools to analyze work evidence, identify outliers, and provide productivity insights.

Responsibilities:

• Led backend development and integrations with Jira, Google, GitHub, and Bitbucket
• Managed and processed large datasets for evaluation algorithms
• Implemented daily auto-update tasks and custom SQL queries for analytics charts
• Developed Docker automation scripts and backend obfuscation workflows

PuzzlePizza (Kitchen Management System) - Back-End Developer

Duration: May 2022 – Feb 2023

Technologies: NestJS, PostgreSQL, AWS, Stripe, Square, Redis, Monorepo

About the project: Kitchen management system with mobile and self-terminal backends.

Responsibilities:

• Developed database schema and architecture from scratch
• Handled client, admin, and printer services
• Integrated POS terminals and printers
• Integrated Stripe/Square payments and implemented SSR admin panel

Amres / Nextres (Investment Lending Platform) - Backend Developer / Team Lead

Duration: Jan 2022 – May 2022

Technologies: Node.js, NestJS, Express, Carbone.io, MongoDB, PostgreSQL, AWS

About the project: Multi-service investment lending platform.

Responsibilities:

• Supported and extended platform functionality
• Developed admin panel for document generation (management, sorting, attribute matrices, template conversion to DOCX/PDF)
• Implemented e-signature service with platform integration, step logs, and email notifications

Fatster / Nutrimis (Social Fitness App) - Back-End Developer

Duration: Aug 2021 – Jan 2022

Technologies: NestJS, Express, TypeScript, PostgreSQL, WebSockets, AWS

About the project: Social fitness app aimed at weight loss.

Responsibilities:

• Supported and enhanced backend functionality
• Implemented WebSocket chat server and optimized SQL queries
• Automated build process via Jenkins and improved server architecture
• Added premium features (subscriptions, in-app purchases, user statistics)

CPayments (Cryptocurrency Exchange) - Back-End Developer

Duration: Apr 2021 – Aug 2021

Technologies: NestJS, Express, TypeScript, PostgreSQL, SSE

About the project: Upgrade of an existing cryptocurrency exchange platform.

Responsibilities:

• Developed Bitcoin buy/sell functionality
• Designed database schema and built client and admin backends
• Implemented callback server and launched Bitcoin node
• Added real-time updates using Server-Sent Events (SSE)

TrafficApps (Mobile App Advertising Platform) - Back-End Developer

Duration: Dec 2020 – Aug 2021

Technologies: NestJS, Express, TypeScript, MySQL, AWS (EC2, RDS, S3, SES)

About the project: Platform for mobile application advertising.

Responsibilities:

• Built REST APIs and payment integrations (fiat/crypto)
• Worked with Facebook Ads Manager
• Implemented traffic filtering settings based on various parameters
• Developed SSR admin panel

Test Orchestrator (CI Testing Framework) - Back-End Developer

Duration: Aug 2020 – Mar 2021

Technologies: NestJS, Express, TypeScript, MySQL, AWS (EC2, SES)

About the project: Framework for managing unit and UI tests in Continuous Integration (CI).

Responsibilities:

• Designed backend architecture and database schema
• Integrated open-source frameworks for virtual device test execution
• Managed backend and frontend deployments