Nick

Mykola Marchenko
SENIOR .NET DEVELOPER
Full Stack · Logistics and Operational Systems
[відкрити контакти](див. вище в блоці «контактна інформація») | [відкрити контакти](див. вище в блоці «контактна інформація») | https://t.me/Nick_Marchenko | Dnipro, Ukraine

—SUMMARY—

Senior Full Stack .NET Developer with 7+ years of experience in developing high-load distributed systems. Developed
mission-critical payment platforms at PrivatBank for millions of daily users. At Epicenter K, I develop a real-time
logistics platform: interactive Canvas visualization of infrastructure, live transport tracking via SignalR, and
event-driven architecture on RabbitMQ. Expertise in CQRS, JWT/OAuth, hardware protocols, and .NET Framework
→ .NET 8 migration.

—PROFESSIONAL EXPERIENCE—

Senior .NET Developer / Tech Lead, Epicentr K 2023 – Present

Project: Logistics Portal
Description: An internal platform for managing the logistics infrastructure of Ukraine’s largest DIY chain. Interactive
real-time map of warehouses, parking lots, and transportation.
Responsibilities: Development of Canvas-based infrastructure visualization; real-time transportation tracking using
SignalR; operator control interface; role-based access control system; Telegram notifications for drivers;
event-driven architecture on RabbitMQ; leading a team of 3 people.
Technologies: .NET 8, ASP.NET, Angular, TypeScript, HTML Canvas, MSSQL, Dapper, RabbitMQ, SignalR,
Elasticsearch, Kibana, Telegram Bot API, Docker, GitHub Actions.
Achievements: ●​Built the platform from scratch—from architecture to production—as Tech Lead.
●​A unified system covers hundreds of physical locations across Ukraine in real time.
●​Canvas visualization without third-party mapping libraries.

Junior → Senior .NET Developer, PrivatBank 2017 – 2023

Project: iPOS — Mobile Payment Processing
Description: A mobile payment processing system—a physical device connects to a smartphone and accepts card
payments. A personal dashboard for merchants, couriers, and sole proprietors.
Responsibilities: Development of the backend for transaction acceptance and authorization; integration with bank
processing; client dashboard — transaction history, terminal management, access delegation.
Technologies: .NET, ASP.NET Core, C#, Backbone.js, MSSQL, Dapper, Docker, ELK Stack.
Achievements: ●​The system processed hundreds of thousands of transactions per day.
●​Mastered the payment development stack and implemented coding standards within the team.
●​The high-load async pipeline handled peak traffic without any performance degradation.

Project: AutoCash — Cash Recounting System
Description: Automation of cashiers’ work at cash recounting centers. Integration with cash counters using a serial
port.
Responsibilities: Development of the UI and backend for cashiers; integration module with the cash counting machine —
reverse engineering of the COM protocol, parsing of the byte stream, form autofill; closing the cash
shift.
Technologies: .NET 8, ASP.NET Core, MSSQL, Dapper, Serial Port (COM), Docker, ELK Stack.
Achievements: ●​I reverse-engineered the calculator's COM protocol on my own.
●​The module underwent a complete stack migration: .NET Framework → .NET Core → .NET 8.
●​Autofilling forms from a byte stream reduced the time it took a cashier to process a single cash bag.
●​Eliminated manual entry of denominations and reduced the error rate among cashiers during counting.

Project: Terminal — NFC Acquiring
Description: The next generation of acquiring (using a phone’s NFC functionality). Replacement for iPOS.
Responsibilities: Client web dashboard—SSO, full transaction cycle, refunds, electronic receipts; integration with PRRO
(Ukrainian tax authority); CQRS + Clean Architecture under high load.
Technologies: .NET 7, ASP.NET Core, MSSQL, Dapper, SignalR, Docker, ELK Stack.
Achievements: ●​~1 million transactions per day.
●​Implemented CQRS and Clean Architecture within the team.
●​Worked with the banking team to develop an integration protocol with the PRRO.

Project: Electronic Cashier (ECP) — Replacing Cashiers at Branches.
Description: Self-service cash operations using a tablet — safe machine handles accept and dispense. Full cashier
replacement.
Responsibilities: Software wrapper over the safe machine API via TCP/IP; integration with “My Terminal,” POS
terminals, and bank processing; Prometheus monitoring of device capacity.
Technologies: .NET 8, ASP.NET Core, TCP/IP, MSSQL, Dapper, Prometheus, Grafana, Docker, ELK Stack.
Achievements: ●​We covered the entire API for ATM machines without manufacturer documentation.
●​The system simultaneously manages hundreds of devices in real time across Ukraine.
●​Prometheus monitoring of device occupancy has reduced downtime for operators.
●​Integration with “My Terminal” has made the switch to EKP transparent for the operator—a single
workflow for cash and cards.
●​The customer independently performs all transactions using a tablet.

—TECHNICAL SKILLS—

Languages: C#, TypeScript, JavaScript, SQL, T-SQL.
Backend: .NET 6 / 7 / 8, ASP.NET Core, ASP.NET MVC, Web API, WCF, SOAP, gRPC, Windows Services,
Blazor, Ocelot API Gateway.
Frontend: Angular, Razor, jQuery, HTML / CSS / SCSS, Bootstrap, Kendo UI, DevExpress, Canvas API.
ORM / Data Access: Entity Framework Core, Dapper, ADO.NET, NHibernate, LINQ.
Databases: SQL Server, Oracle DB, PostgreSQL, MySQL, SQLite, MongoDB, Redis.
Architecture: CQRS, Clean Architecture, DDD, Microservices, REST API, GraphQL, SOLID, OOP / OOD.
Auth & Security: JWT, OAuth 2.0, Cookie-based auth, RBAC, ASP.NET Core Identity.
Messaging / Realtime: RabbitMQ, Azure Service Bus, SignalR, Telegram Bot API, Viber API.
Search / Cache: Elasticsearch, ElasticAPM, Redis, Hangfire.
Cloud / DevOps: Docker, Kubernetes, GitHub Actions, GitLab CI, Jenkins, nginx, IIS.
Testing: NUnit, xUnit, SpecFlow (BDD), Unit tests, Integration tests.
Integrations: Ukrainian tax authority (ПРРО), Serial Port / IP hardware protocols, Salesforce, SharePoint, BankId.
Tools: Git, SVN, TFS, Swagger / OpenAPI, Postman, Jira, NLog, Serilog, Coralogix, PuppeteerSharp
(headless Chromium), zxing.net.

—EDUCATION—
National Mining University, Dnipro
M.Sc. System Software — with honours 2013 – 2015
M.Sc. Environmental Economics — with honours 2009 – 2013

—LANGUAGES—
Ukrainian (Native), Intermediate (reading/writing), Russian (Native).