Ihor Romanchuk
Verified Expert in Engineering
Software Developer
Kraków, Poland
Toptal member since March 18, 2020
Ihor is an experienced senior full-stack web developer with a strong track record of delivering quality products. Proficient in multiple technologies, he excels in crafting custom projects, making informed architectural decisions, and managing databases, back ends, front ends, cloud hosting, CI/CD, and more. Currently, Ihor focuses on front-end development using React, TypeScript, and JavaScript. His dedication and adaptability make him a valuable asset for any project.
Portfolio
Experience
- SQL - 11 years
- CSS - 11 years
- C# - 11 years
- JavaScript - 11 years
- TypeScript - 6 years
- ASP.NET Core - 6 years
- React - 6 years
- Amazon Web Services (AWS) - 5 years
Availability
Preferred Environment
Docker, Amazon Web Services (AWS), React, TypeScript, Node.js, C#, SQL, SQL Management Studio
The most amazing...
...web service I helped develop is called JustAnswer. It required extensive, in-depth testing, refactoring, complex integrating, and creating bug-free solutions.
Work Experience
Senior Full-stack Developer
CertifyOS
- Implemented a redesign of the Provider Details page within a Toptal Team, reducing total development time by 50% by creating a reusable table component using MUI Datagrid with inline editing and validation.
- Executed end-to-end testing using Cypress for the newly developed reusable table component, ensuring its functionality and reliability.
- Enhanced efficiency by setting up API client code generation with RTK Query code generation tool, resulting in a 30% reduction in front-end development time as developers no longer need to define new functions and models for API methods manually.
- Strengthened the reliability and robustness of the NestJS API by adding a comprehensive suite of unit tests, ensuring code integrity and minimizing potential regressions.
- Improved database entities using TypeORM by implementing enums where appropriate, enhancing data consistency and query efficiency.
- Actively participated in team collaboration activities, supporting team members, conducting code reviews, and contributing improvement ideas to enhance overall project quality and efficiency.
Lead Front-end React Developer
Syntracts, Inc.
- Developed a cutting-edge website for a generative AI tool, utilizing Next.js, React, and TypeScript, ensuring pixel-perfect precision and seamless user experience.
- Completed the entire website development within a tight deadline of three weeks, optimizing project efficiency and exceeding client expectations.
- Collaborated closely with clients, back-end developers, and designers to understand project requirements and deliverables.
- Implemented responsive design principles, ensuring optimal performance on both desktop and mobile platforms.
- Integrated authentication and sharing features, enhancing user accessibility and collaboration.
- Incorporated Google Analytics to track user behavior and website performance, enabling data-driven decision-making and iterative improvements.
Lead Full-stack Developer
Realtyshoot
- Developed an app that connects real estate owners with photographers and stagers. It lets them find and choose the photographer and schedule the photo session.
- Fixed multiple problems including the broken Stripe integration.
- Managed one mid-level front-end developer using Jira as a task management tool. Conducted regular code reviews.
- Improved the development setup with a Docker Compose file for local development.
Senior Node.js Engineer
Digible Inc.
- Developed a minimum viable product (MVP) that automates content posting on Facebook and Instagram, enhancing content delivery efficiency.
- Designed multiple content templates for Facebook and Instagram, enriching the MVP's capabilities for diverse posting needs.
- Engineered a rule-based algorithm to generate new social media content, expanding automated content variety.
- Refined TypeScript settings to enable null reference error checking, enhancing code robustness in the existing project.
- Authored a comprehensive technical design document outlining the content-generation process, serving as a blueprint for future development and team member onboarding.
- Automated the development workflow by setting up Github Actions, streamlining build and deployment processes during pull requests.
- Standardized coding practices by configuring ESLint according to the Airbnb JavaScript Style Guide and fixed related errors.
- Collaborated with cross-functional teams to gather requirements and feedback, ensuring the MVP aligned with organizational goals and user needs.
- Conducted rigorous testing and debugging of the MVP, contributing to reliable uptime and minimal rollbacks on deployments.
Senior Full-stack Developer
GeneDx
- Completed a 1.5-year migration project successfully, transitioning from AngularJS to React with TypeScript.
- Implemented new website layouts based on Figma designs, ensuring a modern and intuitive user experience.
- Developed a comprehensive component library, adhering to Figma designs, for seamless integration into the website.
- Reverse-engineered legacy code, enhancing maintainability and scalability by migrating it to a clean and efficient React codebase.
- Expertly managed a complex ordering flow with multiple steps, sub-steps, and fields, including real-time validation and status tracking.
- Implemented data persistence functionality, enabling users to reload the page without losing entered data, enhancing user convenience.
- Integrated React application and standalone React components into the CRM system.
- Successfully set up advanced event tracking using GA4 (Google Analytics 4) and designed a comprehensive technical schema leveraging GTM (Google Tag Manager) to optimize user experience insights and enhance digital strategy.
Senior Front-end Developer
Unilever
- Implemented the designs of several screens with pixel-perfect accuracy.
- Adjusted Material UI components to the design appearance using the theming approach.
- Introduced React development best practices to the project.
Senior Full-stack Developer
Yara
- Developed an app that helps farmers create crop nutrition plans. The app gives you a recommendation on when and how much fertilizer you should apply. Users can view data in different formats like tables and charts and share the plan as a link or PDF.
- Built an app that helps farmers keep track of the farm's sustainability. It calculates the CO2 and N emissions levels compared to benchmarks and gives users improvement suggestions.
- Conducted interviews for junior, mid, and senior positions.
- Demoed new features to other teams and stakeholders.
- Investigated the best graph library for the project, prepared comparisons with showcases, and presented them to the team leads.
- Worked as part of the development team following the Scrum process. Conducted onboarding sessions for newcomers.
Senior Full-stack Developer
ALLEYE
- Implemented a web service called ALLEYE from scratch, helping organize and manage the instrument validation process in the health industry.
- Prepared the architecture and implemented the website that consists of an ASP.NET Core REST API, a React SPA, and an SQL server database hosted in a dockerized Linux container on AWS.
- Implemented features such as a dashboard with plenty of charts, audit trail, authentication and authorization with roles and permissions (using ASP.NET Core Identity and JWT), recurring jobs with Hangfire, and screen lockout after some time of inactivity.
- Transformed the client's requirements into working solutions. Worked following the Scrum methodology, with daily scrums, grooming, planning sessions, and estimates, managing a small team of developers.
- Configured CI/CD with test environment and auto deployments with Azure DevOps and AWS ECS.
Senior Full-stack Developer
Freelance
- Created a React application that generates an HTML page based on data provided in the JSON file, then converted this page into a PDF file using headless Chrome.
- Refactored and added new functionality to websites written in AngularJS, including logic and styles.
- Developed a data parser that took .txt files as input, then red-lined and decoded them from Base64 to parsed JSON, calculated all needed data, and produced a new file with results.
- Communicated with clients from the US, India, and UAE.
- Analyzed requirements, provided estimates, and met deadlines.
Senior Full-stack Developer
e-Boks A/S
- Prepared the architecture for a new product that consisted of several services and a SPA. Created user stories, provided estimates, and built the tracking progress.
- Conducted about 20 interviews for the project so far.
- Created projects from scratch and deepened my knowledge of the security domain.
- Refactored and introduced unit testing in products.
Middle Full-stack Developer
JustAnswer
- Led a subproject, including overseeing the SDD preparation, creating user stories, providing estimates, and tracking progress.
- Spearheaded a data quality initiative within the team. The primary goal was to find problems with tracking, introduce solutions and implement them, and ensure correctness via integration and Selenium tests.
- Refactored many elements, writing dozens of unit, integration, and Selenium tests.
- Conducted extensive A/B testing, including implementing experiments that required several versions of web pages, which differed in UI and functionality. Compared the conversion rate and other metrics of those pages.
- Became deeply familiar with the Scrum methodology here.
- Established and ran code reviews for my teammates.
Junior Full-stack Developer
ByteAnt
- Developed new web pages, including writing styles, JavaScript, database queries, unit tests, and more.
- Optimized the performance of SQL queries via stored procedure optimization and database denormalization, which reduced the load time from 30 seconds to 100 milliseconds.
- Became experienced with ASP.NET MVC, HTML, CSS, JavaScript, jQuery, Angular, Microsoft SQL Server, Elasticsearch, Entity Framework, LINQ, SVN, Git, and TeamCity.
Experience
Realtyshoot
https://realtyshoot.com/Fiona Posts
https://digible.com/I've developed a minimum viable product (MVP) that automates content posting on Facebook and Instagram, enhancing content delivery efficiency. I also designed multiple content templates for Facebook and Instagram, enriching the MVP's capabilities for diverse posting needs.
Provider Portal
https://www.genedx.com/In a 1.5-year migration project for GeneDx's Provider Portal, I led the transition from AngularJS to React with TypeScript. I designed new Figma-based layouts, created a robust component library, and reverse-engineered legacy code for a seamless migration. The complex ordering flow was reimagined, featuring real-time validation, a dynamic side menu, and data persistence, resulting in an intuitive and efficient user experience. The successful project cemented GeneDx's position as a leader in genetic and genomic testing services.
Atfarm
https://www.at.farm/Moreover, it keeps track of the farm's sustainability. It calculates the CO2 and N emissions levels compared to benchmarks and suggests improvements.
ALLEYE CMMS Software
https://www.apsinco.com/alleye-cmms-softwareIt is written in C#, React, and TypeScript and uses SQL server as the database.
I created everything from scratch, which included setting up CI/CD on Azure DevOps with a Git repo and automatic deployments to AWS ECS.
The codebase is covered with unit tests and end-to-end tests using Cypress.io.
Later on, I managed a small team of developers.
JustAnswer
e-Boks
https://www.e-boks.com/danmark/da/Mechanic Advisor
https://www.mechanicadvisor.com/HTML to PDF Conversion
The source code can be found here: https://github.com/likerrr777/PrintHtmlToPdf
Education
Master's Degree in Applied Mathematics and Informatics
Ivan Franko National University - Lviv, Ukraine
Certifications
NestJS Zero to Hero — Modern TypeScript Back-end Development
Udemy
Skills
Libraries/APIs
MediatR, AutoMapper, Recharts, React-Intl, Formik, Yup, React Router, Lodash, REST APIs, React, LINQ, Moq, Entity Framework, Node.js, React Redux, React Hook Form, Handlebars, API Development, D3.js, Flowbite, MobX, jQuery, Serilog, Urql, Puppeteer, YouTube API, Stripe
Tools
Visual Studio, Sequelize, Git, GitHub, SQL Management Studio, Webpack, Figma, Postman, Prisma, Redux Toolkit, RTK Query, JSS, Amazon CloudFront CDN, Hangfire, Amazon Elastic Container Service (ECS), Amazon Elastic Container Registry (ECR), Jira, Google Analytics, Docker Compose, Dynatrace, TFS, TeamCity, AWS IAM, Subversion (SVN), RabbitMQ, CircleCI, ChatGPT
Languages
GraphQL, T-SQL (Transact-SQL), CSS, Sass, Less, TypeScript, JavaScript, HTML, HTML5, SQL, C#, C#.NET, CSS3, ECMAScript (ES6), SCSS, Active Server Pages (ASP), VBScript, Python
Frameworks
ASP.NET Web API, Redux, NestJS, Cypress, NUnit, ASP.NET, ASP.NET Core, Entity Framework Core, JSON Web Tokens (JWT), Swagger, Material UI, .NET, .NET Core, Jest, Next.js, Express.js, Tailwind CSS, ASP.NET Core MVC, ASP.NET MVC, Selenium, React-Bootstrap, Bootstrap, AngularJS, Angular, OAuth 2
Paradigms
REST, FluentValidation, Code First, Unit Testing, Microservices, E2E Testing, Automated Testing, Web Performance Optimization (WPO), Responsive Web Design (RWD), Object-oriented Programming (OOP), Best Practices, Azure DevOps, Database Design, Test-driven Development (TDD), DevOps, Search Engine Optimization (SEO), B2C
Platforms
Visual Studio Code (VS Code), Windows, Software Design Patterns, Docker, Amazon Web Services (AWS), Linux, Vercel, Amazon EC2, AWS Lambda, Twilio, Heroku, Google Cloud Platform (GCP)
Storage
SQL Server Management Studio (SSMS), SQL Server 2017, Microsoft SQL Server, RDBMS, PostgreSQL, Amazon S3 (AWS S3), MySQL, Databases, Datadog, Redis, Elasticsearch, NoSQL, Google Cloud
Industry Expertise
Project Management
Other
Pixel Perfect, Cross-browser Compatibility, Single-page Applications (SPAs), Data Visualization, React Hooks, Axios, Front-end, TypeORM, Authentication, Authorization, APIs, Full-stack, Storybook, SOLID Principles, Multithreading, Apollo, Design Systems, Styled-components, ESLint, Charts, Web Development, MERN Stack, API Integration, Architecture, User Experience (UX), User Interface (UI), UI Components, Back-end, CI/CD Pipelines, Web Applications, UI Libraries, Component Libraries, Front-end Architecture, Front-end Development, SaaS, Algorithms, Minimum Viable Product (MVP), Integration Testing, Full-stack Development, Customer Relationship Management (CRM), Integration, API Gateways, Startups, Material Design, Web UI, Web UX, Charting, Software Architecture, Estimations, A/B Testing, First Contentful Paint (FCP), Responsive UI, Mobile UI, RTK Query Code Generation, Identity, Serverless, PDF, Cryptography, OAuth, Headless Commerce, Animation, Monorepos, Google Analytics 4, Google Tag Manager, Inventory Management, Cloud, Amazon RDS, Web Project Management, Octopus Deploy, Team Management, Segment, Phrase, Chromium, Cryptocurrency, Applied Mathematics, UI Bakery Copilot, Web3, Crypto, Decentralized Finance (DeFi), SEO Tools, WebSockets
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