Nikolay Kazmin, Developer in Sofia, Bulgaria
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Nikolay Kazmin

Verified Expert  in Engineering

Bio

Nikolay holds a master’s in computer science from ETH Zurich and has 15+ years of full-stack web development experience. Before founding his own company, he worked with GuideStar, a major US nonprofit brand. Passionate about Rails and React, he co-founded and led Domestina, a cleaning services marketplace with 170,000+ bookings. Later, Nikolay joined scale-up Cypher Learning to enhance its platform and support its IPO plans.

Portfolio

CYPHER LEARNING INC.
Ruby on Rails (RoR), Back-end, Databases, Ruby, HTML, CSS, JavaScript, APIs...
Domestina
Team Leadership, REST APIs, Back-end, Full-stack, SQL, HTML, Ruby, Leadership...
GuideStar
Back-end, Full-stack, SQL, HTML, Software Engineering, Databases, JavaScript...

Experience

  • CSS - 16 years
  • JavaScript - 16 years
  • MySQL - 15 years
  • Ruby - 15 years
  • Ruby on Rails (RoR) - 15 years
  • Bootstrap - 14 years
  • GitHub - 12 years
  • React - 8 years

Availability

Full-time

Preferred Environment

GitHub, RubyMine, Windows 10

The most amazing...

...web app I've developed is Domestina (Domestina.bg/en). It connects clients with cleaning companies and has more than 170,000 bookings to this date.

Work Experience

Full-stack RoR Senior Developer

2021 - 2025
CYPHER LEARNING INC.
  • Acted as a technical product manager for Cypher Learning’s largest client, translating their needs into scalable features for all customers and implementing the solutions.
  • Implemented time tracking to analyze student engagement across classes and content.
  • Worked on the website design overhaul, leading the development of customizable site colors for each client.
  • Enabled teachers to create custom PDF report cards with student information.
  • Enhanced the permissions system to support cascading roles.
  • Implemented class periods, securing the company's biggest deal in the Middle East.
  • Introduced periodic games in the system's gamification engine.
  • Developed a new Google Drive assignment type, allowing teachers to distribute copies of a document stored in their drive to each student.
  • Integrated Microsoft Excel to support a new report format.
Technologies: Ruby on Rails (RoR), Back-end, Databases, Ruby, HTML, CSS, JavaScript, APIs, MySQL

CTO and Co-founder

2013 - 2021
Domestina
  • Created the software and database designs for the web app from scratch at the start of the company.
  • Led the implementation and continuous evolution of the web app using Ruby on Rails.
  • Enforced good practices in the development team, which included mandatory tests, code reviews, code styling, CI, automated deployment with Capistrano, and server management with Ansible.
  • Recruited two other software engineers and trained them to become an integral part of the development team.
  • Led the transition of the front end from jQuery to React; also implemented the booking process with a complicated but very easy-to-use interface.
  • Integrated the Braintree payment system and developed automatic payments as well as an internal accounting and invoicing system both for Domestina and its contractor partners.
  • Integrated Viber messaging for instant communication with clients and partners.
  • Implemented a huge website redesign in 2019 using React more extensively and modern CSS features.
  • Helped with product development by implementing "Jobs to be Done" interviews with clients and proposed numerous improvements to the product.
  • Created an admin interface for our contractor partners with Materialize CSS and Ruby on Rails.
Technologies: Team Leadership, REST APIs, Back-end, Full-stack, SQL, HTML, Ruby, Leadership, RubyMine, Software Engineering, Databases, JavaScript, CSS, Object-oriented Programming (OOP), Braintree API, Materialize, GitHub, MySQL, React, Ruby on Rails (RoR), Search Engine Optimization (SEO), RSpec, eCommerce, Figma

Senior Software Developer

2011 - 2015
GuideStar
  • Managed the technical part of the transition from Philanthropedia to GuideStar.
  • Developed the improved GuideStar's company profiles with Philanthropedia data.
  • Built integrations with third-party platforms including Salesforce.
  • Contributed to the development of the main website development using C# and ASP.NET MVC.
Technologies: Back-end, Full-stack, SQL, HTML, Software Engineering, Databases, JavaScript, CSS, Microsoft SQL Server, ASP.NET MVC, C#

Senior Software Developer

2009 - 2011
Philanthropedia
  • Developed the back end and front end of the website using Ruby on Rails, jQuery, and CSS.
  • Integrated PayPal payments and created an accounting system for the company.
  • Integrated Philanthropedia's data into GuideStar and oversaw the technical transition after Philantropedia was acquired.
Technologies: Back-end, Full-stack, SQL, HTML, Ruby, Software Engineering, Databases, Object-oriented Programming (OOP), MySQL, CSS, JavaScript, Ruby on Rails (RoR)

Experience

Domestina

http://www.domestina.bg
A marketplace where clients and cleaning companies meet. It has more than 100,000 bookings to this day. The web app automates everything including booking, payment, schedules, pricing, etc.

I started the project on day one and for the past two years, I have been the sole software engineer for all development activities.

Education

2019 - 2020

Executive MBA (EMBA) in Business Administration

American University In Bulgaria - Blagoevgrad, Bulgaria

2008 - 2010

Master's Degree in Computer Science

ETH Zurich - Zurich, Switzerland

2005 - 2008

Bachelor's Degree in Computer Science

Jacobs University Bremen - Bremen, Germany

Skills

Libraries/APIs

Braintree API, React, REST APIs

Tools

RubyMine, GitHub, RSpec, Figma

Languages

CSS, Ruby, HTML, SQL, JavaScript, C#

Frameworks

Ruby on Rails (RoR), Bootstrap, Materialize, ASP.NET MVC

Paradigms

Object-oriented Programming (OOP), Design Patterns, Search Engine Optimization (SEO)

Storage

MySQL, Databases, PostgreSQL, Microsoft SQL Server

Other

Software Engineering, Full-stack, Back-end, Team Leadership, eCommerce, Presentations, Finance, Strategy, Negotiation, Leadership, APIs

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