Iliyan Kupenov
Verified Expert in Engineering
Full-stack Web Developer
Iliyan is a senior full-stack engineer with over seven years of experience building high-grade software products. He has worked with large enterprises and startups alike. He's co-founded a small-scale B2B SAAS platform, where he worked completely hands-on. He was part of the founding team that built a product used by over 6 million users every month. At this stage, he is more focused on the front-end and is interested in applying his knowledge to companies building innovative products.
Portfolio
Experience
Availability
Preferred Environment
React, Visual Studio Code (VS Code)
The most amazing...
...product I've worked on is an enterprise-grade CMS that is powering eCommerce and marketing solutions for clients like Aston Martin, WHO, Nestle, and more.
Work Experience
Full-stack Engineer
Cosiall
- Implemented payment and subscription management, coupons, invoicing, and billing history functionality using Stripe.
- Rolled out a full-fledged OAuth authentication solution using IdentityServer, Razor Pages, and Tailwind.
- Carried out a notification system on both the front and back end using SignalR.
- Implemented significant parts of the back-end system using .NET Core for the REST APIs and PostgreSQL, along with Entity Framework as a data store.
- Designed the public website and the private application using Figma. The public website is a static site generated with Gatsby, which uses a headless CMS as a data store. The data from the CMS is retrieved using GraphQL.
- Added a comprehensive chat system featuring attachments, emojis, and statuses on both the front and back end.
- Integrated external tracking and analytical tools, as well as feature flagging, on the front end.
- Hosted, deployed, and monitored the infrastructure of all the projects and services, using Render and Google Cloud for the hosting.
Front-end Engineer
Bazaarvoice
- Improved team productivity by implementing foundational and reusable core components and enforcing coding standards and conventions.
- Integrated a site-wide A/B testing solution that enabled the marketing and product team to increase conversions and efficiency through the organic and paid acquisition channels.
- Reduced regressions and increased the team's confidence when deploying code to production by integrating end-to-end tests into the pipeline.
- Implemented some of the highest-traffic pages and features, averaging around four million unique visits each month.
Full-stack Engineer
Comcast
- Implemented components for an internal UI library—similar to Material UI and Ant Design—using React.
- Worked heavily with .NET Core for creating REST APIs. SQL Server was used as a database, along with Entity Framework.
- Owned the design of the initial solution for a greenfield project. The solution was modeled with DDD and CQRS in mind.
- Worked on establishing best practices and their enforcement in the codebase.
Full-stack Engineer
Progress
- Worked on the core team of Sitefinity, a heavily customizable enterprise-grade CMS.
- Integrated a large-scale front-end migration from WebForms to Angular.
- Took the initiative to improve some internal processes by creating an internal tool that made it easier to benchmark the existing solution and visualize bottlenecks and potential errors.
Experience
Cosiall
https://www.cosiall.comInfluenster
https://www.influenster.comSitefinity
https://www.progress.com/sitefinity-cmsI was responsible for improving the product's performance and reliability and developing new complex features. The solution was mainly written in .NET Webforms and .NET MVC, using AngularJS on the front end. Later on, we started migrating the front end to Angular 2+, which I worked on exclusively for several months.
Internal MDM
Med Talent Solutions
My job was to create a brand identity appropriate for their target customers, design a logo, and implement the whole solution using Webflow.
Meetup
Skills
Languages
C#, JavaScript, HTML, CSS, TypeScript, SCSS, Java, Swift
Frameworks
.NET, .NET Core, Tailwind CSS, Next.js, Entity Framework Core, Angular, AngularJS, Fastify, Windows PowerShell, Razor Pages, Express.js, Redux
Libraries/APIs
Entity Framework, React, Stripe, Stripe API, SendGrid API, Twilio API, Node.js, jQuery, NServiceBus, SignalR, Google APIs, Passport.js
Tools
Visual Studio, GitHub, Notion, PostCSS, Azure DevOps Services, Jira, Sentry, Figma, SendGrid, Git, RabbitMQ, Docker Compose, NGINX, FullStory, Terraform
Platforms
Webflow, Webflow CMS, Netlify, Visual Studio Code (VS Code), Twilio, Taplytics, Docker, Heroku, Algolia, Mixpanel, Amazon Web Services (AWS)
Other
Prismic, React Hook Forms, Chakra UI, Front-end Development, Back-end Development, Styled-components, Front-end, React Query, Web Security, Gatsby, Framer Motion, IIS, Identity Server, Slate.js, HubSpot CRM, MassTransit, Design, User Interface (UI), Flagsmith, Render
Storage
Microsoft SQL Server, MongoDB, PostgreSQL, Datadog, Google Cloud
Certifications
Veracode Application Security
Veracode
Software Academy Graduate
Telerik Academy
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