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Alexander Kuchinsky

Verified Expert in Engineering

Senior Full-stack Application Developer

Winnipeg, MB, Canada

Toptal member since June 18, 2025

Expertise

Full-stack Web Development Back-end Developers Integration Front End Cloud Engineering CSS JavaScript C#REST API SQL .NET Auth0

Bio

Alexander is an application and database developer with over 20 years of practical experience in the software development industry. As a Microsoft Certified Trainer, he taught Microsoft programming technologies in various Microsoft certification centers in Israel. Alexander also holds the following Microsoft certificates: MCP, MCAD, MCSD, MCTS, MCITP, MCPD, and MCT, as well as a master's degree in computer science and IT systems from Nikolayev State University in Ukraine.

Portfolio

DNSFilter

Python, .NET, Java, Go, Node.js, Angular, React, HTML, CSS, TypeScript...

Teranet Manitoba

.NET, Java, Go, Apache Kafka, Spring Boot, PostgreSQL, Microsoft SQL Server...

The North West Company

.NET, Microsoft SQL Server, JavaScript, HTML, CSS, Angular, C#, REST APIs...

Experience

Microsoft SQL Server - 20 years
.NET - 20 years
Java - 17 years
MySQL - 13 years
PostgreSQL - 13 years
Node.js - 12 years
Angular - 8 years
React - 6 years

Preferred Environment

.NET, Java, Node.js, Python, Go, React, Angular, Microsoft SQL Server, PostgreSQL, MongoDB, C#, Express.js

The most amazing...

...thing I've developed is the Avaya call center management and monitoring system, which became Avaya's main management and monitoring product.

Work Experience

Staff/Senior Software Engineer

2021 - 2025

DNSFilter

Participated in architectural design at various levels to align with business needs and maintain product quality standards.
Assessed new technologies and implemented proof of concepts (POCs) as part of the evaluation process.
Developed the front and back end of a threat detection and content filtering system. Fixed bugs and provided maintenance and ongoing support.
Participated in client-facing troubleshooting sessions to achieve client satisfaction.
Collaborated with business, product, platform, support, QEs, and other development teams to deliver a product that meets business and quality requirements.
Headed technical interviews with candidates. Mentored and coached junior, intermediate, and senior developers.
Managed multiple tasks effectively through time management and prioritization.
Implemented clean code and SOLID principles to meet business requirements, code quality requirements, and deadlines.
Implemented CI/CD pipelines and performed DevOps tasks.

Technologies: Python, .NET, Java, Go, Node.js, Angular, React, HTML, CSS, TypeScript, JavaScript, PostgreSQL, Redis, Git, GitHub Actions, Apache Kafka, AWS IoT, Spring Boot, Hibernate, Microservices, GraphQL, Android, C#, REST APIs, DevOps, CI/CD Pipelines, Full-stack, Web Development, Back-end, SQL, APIs, Amazon Web Services (AWS), Express.js, NestJS, Amazon RDS, Relational Database Services (RDS), Web Security, Architecture, Back-end Architecture, Back-end Development, Large-scale Projects, Docker, Kubernetes, Real-time Systems, API Integration, Web Scraping, C#.NET, FastAPI, AWS Lambda, Full-stack Development, Integration, Event-driven Architecture, Amazon Simple Queue Service (SQS), Kafka Streams, Cloud, Logging, HTML5, .NET Core, Tailwind CSS, Minimum Viable Product (MVP), Startups, .NET 8, REST, Redux, Next.js, Technical Leadership, Front-end Development, Cloud Infrastructure, SaaS, Leadership, Communication, RESTFul APIs, Database Design, Microservices Architecture, API Development, WebSockets, Amazon S3 (AWS S3), Front-end, React Native, Distributed Architecture, Distributed Systems, Single Sign-on (SSO), Okta, Auth0, Back-end APIs, Containerization, Software Architecture, Agile, OWASP, Azure PaaS, AWS Cloud Development Kit (CDK), RPC, OAuth 2, GoLand, Datadog, JSON Web Tokens (JWT), Pub/Sub, Stripe, Role-based Access Control (RBAC), Payment APIs, Events, GitHub

Lead Software Developer

2018 - 2021

Teranet Manitoba

Developed critical government systems using SOLID principles, developing back end, front end, and API components.
Participated in the creation of business requirements.
Took part in architecture design and technology selection across various levels, from high to low, contributing to decision-making processes. Evaluated new technologies and implemented POCs.
Collaborated with business, business analysts, and testers to deliver a product that meets business and quality requirements.
Fixed bugs continuously while providing maintenance and ongoing support.
Mentored and coached junior and intermediate developers through code reviews and evaluations.
Managed deployments on Azure and on-premise environments, as well as DevOps tasks.
Met deadlines and requirements for all production work orders consistently.
Performed multi-tasking with time management and prioritization.

Technologies: .NET, Java, Go, Apache Kafka, Spring Boot, PostgreSQL, Microsoft SQL Server, Elasticsearch, MongoDB, HTML, CSS, React, Angular, JavaScript, TypeScript, Git, Azure, AWS IoT, Entity Framework, Hibernate, GraphQL, Microservices, C#, REST APIs, DevOps, CI/CD Pipelines, Full-stack, Web Development, Back-end, SQL, APIs, Amazon Web Services (AWS), Amazon RDS, Relational Database Services (RDS), Content Management Systems (CMS), Web Security, Architecture, Back-end Architecture, Back-end Development, Docker, Kubernetes, API Integration, C#.NET, ASP.NET, Razor, AWS Lambda, Full-stack Development, Event-driven Architecture, Amazon Simple Queue Service (SQS), Kafka Streams, Cloud, Logging, HTML5, Vue, .NET Core, Minimum Viable Product (MVP), Blazor, REST, Redux, Webpack, Technical Leadership, Front-end Development, Cloud Infrastructure, SaaS, Communication, Google Cloud Platform (GCP), ETL, RESTFul APIs, Database Design, Microservices Architecture, API Development, WebSockets, Front-end, Distributed Architecture, Distributed Systems, Auth0, Back-end APIs, Containerization, Software Architecture, Agile, Test-driven Development (TDD), OWASP, Azure Event Hubs, Azure PaaS, MariaDB, Apache Tomcat, Red Hat Linux, Spring MVC, RPC, OAuth 2, JSON Web Tokens (JWT), Pub/Sub, Django, Stripe, Role-based Access Control (RBAC), Payment APIs, Events, GitHub

Lead Software Developer

2018 - 2018

The North West Company

Maintained, enhanced, and supported the existing retail system.
Designed, developed, and enhanced the existing and new retail management tools.
Maintained and developed bug fixes continuously while providing ongoing support.
Met deadlines and requirements for all production work orders consistently.
Recommended architectural improvements, technologies, design solutions, and integration solutions.

Technologies: .NET, Microsoft SQL Server, JavaScript, HTML, CSS, Angular, C#, REST APIs, Full-stack, Web Development, Back-end, SQL, APIs, Web Security, Architecture, Back-end Architecture, Back-end Development, API Integration, C#.NET, Full-stack Development, Integration, Logging, HTML5, .NET Core, ASP.NET MVC, Minimum Viable Product (MVP), REST, Technical Leadership, Front-end Development, Communication, RESTFul APIs, Database Design, API Development, Front-end, Back-end APIs, Software Architecture, OWASP, OAuth 2, Payment APIs, Events

Senior Software Developer

2015 - 2018

DXC Technology

Engineered the back end, front end, and API components for crucial government systems.
Utilized test-driven development (TDD) to develop code while following SOLID principles and clean code methodology.
Maintained the system and fixed bugs to ensure system stability and reliability. Met deadlines and requirements for all production work orders.
Recommended architectural improvements, design solutions, and integration solutions.

Technologies: Java, .NET, Angular, React, HTML, CSS, JavaScript, TypeScript, Apache Kafka, Spring Boot, Microsoft SQL Server, MongoDB, Git, Azure, Microservices, Entity Framework, Hibernate, C#, REST APIs, Full-stack, Web Development, Back-end, SQL, APIs, Content Management Systems (CMS), Web Security, Architecture, Back-end Architecture, Back-end Development, API Integration, C#.NET, ASP.NET, Razor, Full-stack Development, Integration, Cloud, Logging, HTML5, .NET Core, ASP.NET MVC, Minimum Viable Product (MVP), REST, Webpack, Technical Leadership, Front-end Development, Enterprise, Communication, RESTFul APIs, Database Design, API Development, WebSockets, Front-end, Back-end APIs, Software Architecture, Agile, OWASP, OAuth 2, Pub/Sub, Role-based Access Control (RBAC), Events

Senior Software Engineer

2014 - 2015

NCR

Developed the back end, front end, and API components for high-load retail systems.
Participated in creating a low-level systems design document (SDD) and conducted training for junior team members.
Utilized TDD to develop code while following SOLID principles and clean code methodology.
Maintained the system and fixed bugs to ensure system stability and reliability. Met deadlines and requirements for all production work orders.
Recommended architectural improvements, design solutions, and integration solutions.

Technologies: .NET, JavaScript, Microsoft SQL Server, MongoDB, Elasticsearch, RabbitMQ, NHibernate, HTML, CSS, C#, Full-stack, Web Development, Back-end, SQL, APIs, Web Security, Architecture, Back-end Architecture, Back-end Development, Large-scale Projects, API Integration, C#.NET, Full-stack Development, Integration, Logging, jQuery, HTML5, ASP.NET MVC, Front-end Development, Enterprise, ETL, Database Design, API Development, Front-end, Back-end APIs, Software Architecture, Agile, Test-driven Development (TDD), OWASP, Pub/Sub, Role-based Access Control (RBAC), Payment APIs, Events

Tech Lead and Senior Software Engineer

2013 - 2014

Racana

Designed and developed statistical and analytical systems based on large offline and online databases.
Participated in the entire process from market requirements document (MRD) to high-level design (HLD), identifying relevant technologies for implementation.
Developed the back and front end of web applications and cloud services.
Established compatibility with third-party software products by developing a program for modification and integration.
Met deadlines and requirements for all production work orders.
Proposed technical feasibility solutions for new functional designs and suggested options for performance improvement of technical objects.
Provided methodologies for object-oriented software development and efficient database design.
Recommended architectural improvements, design solutions, and integration solutions.
Developed data architecture design to enable analysts to perform targeted customer analysis.
Utilized a pipe and filter model to find bottlenecks and enable measurement of system resource usage and process behavior at the boundary limits of all operations.

Technologies: Python, .NET, Node.js, JavaScript, Redis, Microsoft SQL Server, Elasticsearch, MongoDB, HTML, CSS, Oracle, C#, REST APIs, Full-stack, Web Development, Back-end, SQL, APIs, Express.js, Content Management Systems (CMS), Web Security, Architecture, Back-end Architecture, Back-end Development, Large-scale Projects, API Integration, Web Scraping, C#.NET, ASP.NET, FastAPI, Full-stack Development, Integration, Cloud, Logging, jQuery, ASP.NET MVC, Minimum Viable Product (MVP), Startups, REST, Technical Leadership, Front-end Development, Communication, ETL, RESTFul APIs, Database Design, API Development, WebSockets, Front-end, Back-end APIs, Software Architecture, Agile, Pub/Sub, Role-based Access Control (RBAC), Payment APIs, Events

Tech Lead and Senior Software Engineer

2012 - 2013

Idioma Solutions

Designed and developed real-time management and administration of cloud services and web applications based on large offline and real-time databases.
Participated in the entire process from MRD to HLD, identifying relevant technologies for implementation.
Engineered back- and front-end components for web and Windows applications, as well as cloud services.
Established compatibility with third-party software products by developing a program for modification and integration.
Maintained and fixed bugs and patch sets for the existing web applications.
Designed a strategic plan for component development practices to support future projects. Met deadlines and requirements for all production work orders.
Proposed technical feasibility solutions for new functional designs and suggested options for performance improvement of technical objects.
Recommended methodologies for object-oriented software development and efficient database design, as well as architectural improvements, design solutions, and integration solutions.
Developed data architecture design to enable analysts to perform targeted customer analysis.

Technologies: Redis, JavaScript, .NET, Node.js, Go, Python, MySQL, Elasticsearch, PHP, Android, C#, REST APIs, Full-stack, Web Development, Back-end, SQL, APIs, Express.js, Content Management Systems (CMS), Web Security, Architecture, Back-end Architecture, Back-end Development, Large-scale Projects, API Integration, C#.NET, ASP.NET, Full-stack Development, Integration, Cloud, Logging, jQuery, ASP.NET MVC, Minimum Viable Product (MVP), Startups, REST, Technical Leadership, Front-end Development, Communication, ETL, RESTFul APIs, Database Design, API Development, Front-end, Back-end APIs, Software Architecture, Agile, Pub/Sub, Flask, Payment APIs, Events

Tech and Team Lead

2005 - 2012

IT Navigator (acquired by Avaya)

Designed and developed telecom billing, real-time management, and administration of web and Windows applications based on large offline and real-time databases.
Participated in the entire process from MRD to HLD, identifying relevant technologies for implementation.
Developed the back and front end of web and Windows applications.
Created a customized application based on Avaya technologies and integrated it with CRM, ERP, and proprietary customer applications for seamless functionality.
Established compatibility with third-party software products by developing a program for modification and integration.
Maintained and fixed bugs and patch sets for the existing web applications. Met deadlines and requirements for all production work orders.
Proposed technical feasibility solutions for new functional designs and suggested options for performance improvement of technical objects.
Managed a team of up to five people and trained junior team members.
Recommended methodologies for object-oriented software development and efficient database design, as well as architectural improvements, design solutions, and integration solutions.

Technologies: .NET, Java, Python, Node.js, Microsoft SQL Server, PostgreSQL, MongoDB, Redis, Elasticsearch, Oracle, JavaScript, ActiveMQ, HTML, CSS, Entity Framework, C#, REST APIs, Full-stack, Web Development, Back-end, SQL, APIs, Express.js, Content Management Systems (CMS), Web Security, Architecture, Back-end Architecture, Back-end Development, Real-time Systems, API Integration, Web Scraping, C#.NET, ASP.NET, Full-stack Development, Integration, Logging, jQuery, ASP.NET MVC, Minimum Viable Product (MVP), Startups, REST, Technical Leadership, Front-end Development, Leadership, Communication, ETL, RESTFul APIs, Database Design, API Development, Front-end, Single Sign-on (SSO), Back-end APIs, Software Architecture, Pub/Sub, Flask, Role-based Access Control (RBAC), Events

Part-time Microsoft Certified Trainer

2005 - 2010

Microsoft Education Center Kamtec

Taught groups of 30 adults to use .NET and Microsoft SQL Server technologies.
Enabled individuals without prior software development experience to secure their first software developer positions after completing my one-year course.
Performed four-hour coach sessions twice per week in the evenings.

Technologies: Coaching, .NET, Microsoft SQL Server, C#, Full-stack, Web Development, Back-end, SQL, APIs, Back-end Development, C#.NET, ASP.NET, Full-stack Development, Communication, Database Design

Senior Application Developer

2004 - 2005

TeleLine

Designed and developed a statistical web application based on N-tier technologies.
Selected technologies, coded, and debugged complex applications that delivered customized customer data through multiple interfaces.
Developed WAP-based application for various types of end devices and mobile operating systems.

Technologies: .NET, Microsoft SQL Server, HTML, CSS, C#, Full-stack, Web Development, Back-end, SQL, APIs, Web Security, Architecture, Back-end Architecture, Back-end Development, API Integration, C#.NET, ASP.NET, Full-stack Development, Integration, Logging, Front-end Development, Database Design, Front-end

Windows Application and Web Programmer

1999 - 2004

Mykolaiv River Port

Designed and developed economic, book-keeping, billing, and engineering applications.
Designed, prototyped, coded, debugged, analyzed, and solved problems in multiple application modules.
Maintained and fixed bugs and patch sets for the existing web applications.

Technologies: Delphi, Visual Basic, InterBase, Active Directory (AD), HTML, CSS, Integration, Database Design

Experience

Avaya NAV360

I was the main back-end, front-end, and database developer for the Avaya NAV360 product. This unified software management solution, developed by ITNavigator, was later acquired by Avaya. It manages various Avaya and third-party products, particularly in the contact center space. It played a key role in integrating legacy Nortel and Avaya components after Avaya's acquisition of Nortel. NAV360 is used to manage multiple Avaya and third-party solutions like Nortel, Verint, Genesys, NICE, and various CRM solutions.

wywy GmbH

I was a main back-end, front-end, database, and Android developer for wywy GmbH, a German company specializing in synchronized broadcast detection and interactivity solutions for TV. They provide technology that allows for real-time synchronization between TV broadcasts and accompanying applications on second screens like smartphones and tablets. This enables interactive TV experiences, such as viewers getting additional information, sharing content, or making purchases related to what they watch.

Racana Content Recommendation

I was a main back-end, front-end, and database developer at Racana, where I developed a cloud-based solution for personalized mobile content recommendation and monetization. This project received the Global Innovation Award at Nokia Siemens Networks' Israel Innovation Competition for its ability to create new revenue streams for mobile operators.

NCR Voyix Loyalty

https://www.ncrvoyix.com/retail/loyalty

I participated in developing the back end for the NCR Voyix Loyalty module in a team of 10 developers. Currently, this module is a stand-alone product that operates in more than 20,000 stores worldwide.

NCR Voyix Payments

https://www.ncrvoyix.com/retail/payments

As a member of a team of six developers, I developed NCR Voyix Payments products, enabling commerce with a cloud-based gateway platform and fully integrated and secured end-to-end credit card processing.

NCR Voyix Back Office Anywhere

As a lead developer of a team of five developers and one QA team member, I developed NCR Voyix Back Office Anywhere, which provides management of products, stores, cashiers, point of sales, self-checkouts, customers, promotions, restrictions, payment methods, and many others.

Wildfires Management System

I was a lead developer in a team of five. Over 2.5 years, we developed a wildfire management system for the Government of Alberta. However, this project was not completed because the government did not approve financing for the client, and it was postponed.

The North West Company Retail Suit

As a lead developer in a team of three developers, I created their retail system for grocery stores. However, this project was closed because executives changed their decision, and the company decided to purchase a white label license from NCR.

Property Registry

https://www.teranetmanitoba.ca

I led a team of eight developers and developed the property registry system. This system provides registry service solutions for Manitoba's land titles registry and personal property registry. The system certifies titles to land, maintains land and survey records, and administers the registration of financial interests in personal property for the Province of Manitoba.

Secure DNS Filtering

https://www.dnsfilter.com

Acted as a staff software engineer across three development teams of 18 developers. I developed the back end, front end, and database for the DNSFilter product, which filters DNS traffic to prevent unwanted web resources and protect end users.

Education

1993 - 1999

Master's Degree in Computer Sciences and Information Technologies

Admiral Makarov National University of Shipbuilding - Mykolaiv, Ukraine

Microsoft

Skills

Libraries/APIs

Node.js, React, Entity Framework, REST APIs, API Development, Back-end APIs, jQuery, Stripe, Vue

Tools

Logging, GitHub, Git, Amazon Simple Queue Service (SQS), Kafka Streams, Webpack, Auth0, Apache Tomcat, GoLand, Microsoft Dynamics CRM, ActiveMQ, RabbitMQ, AWS Cloud Development Kit (CDK)

Languages

Java, HTML, CSS, JavaScript, TypeScript, C#, SQL, C#.NET, HTML5, Python, Go, GraphQL, Delphi, Visual Basic, PHP

Frameworks

.NET, Angular, Express.js, ASP.NET, .NET Core, ASP.NET MVC, .NET 8, OAuth 2, JSON Web Tokens (JWT), Spring Boot, Hibernate, NestJS, Razor, Tailwind CSS, Blazor, Redux, Next.js, Flask, NHibernate, React Native, Spring MVC, Django

Paradigms

Microservices, Back-end Architecture, Event-driven Architecture, REST, Database Design, Microservices Architecture, Agile, Test-driven Development (TDD), Role-based Access Control (RBAC), DevOps, Real-time Systems, ETL

Platforms

Azure PaaS, Apache Kafka, Azure, AWS IoT, Android, Amazon Web Services (AWS), Docker, AWS Lambda, Azure Event Hubs, Oracle, Kubernetes, Google Cloud Platform (GCP), Red Hat Linux

Storage

Microsoft SQL Server, PostgreSQL, MySQL, MongoDB, Redis, Elasticsearch, Amazon S3 (AWS S3), MariaDB, InterBase, Datadog

Other

Computer Science, Full-stack, Web Development, Back-end, APIs, Web Security, Architecture, Back-end Development, API Integration, Full-stack Development, Integration, Cloud, Minimum Viable Product (MVP), Technical Leadership, Front-end Development, RESTFul APIs, Front-end, Pub/Sub, Payment APIs, Events, Coaching, Active Directory (AD), GitHub Actions, CI/CD Pipelines, Amazon RDS, Relational Database Services (RDS), Content Management Systems (CMS), Large-scale Projects, Web Scraping, FastAPI, Startups, Enterprise, Cloud Infrastructure, SaaS, Leadership, Communication, WebSockets, Distributed Architecture, Distributed Systems, Single Sign-on (SSO), Okta, Containerization, Software Architecture, OWASP, RPC

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