Milko Lorinkov
Verified Expert in Engineering
Software Architecture Developer
Sofia, Bulgaria
Toptal member since August 1, 2018
With a career spanning over a decade and a half as an architect and software engineer, Milko brings a wealth of expertise to crafting highly available, data-intensive, RESTful enterprise-level systems using Node.js, React, and TypeScript. He meticulously analyzes solutions, excels in diverse industries, from architecting scalable back-end systems to designing intuitive user interfaces, and consistently exceeds client expectations as a freelancer dedicated to innovation and excellence.
Portfolio
Experience
- Software Architecture - 15 years
- TypeScript - 12 years
- Responsive Web Apps - 8 years
- React - 6 years
- Material UI - 6 years
- Node.js - 5 years
- Express.js - 5 years
- Next.js - 4 years
Availability
Preferred Environment
Git, MacOS, Node.js, React, Azure, Amazon Web Services (AWS), Next.js, Visual Studio Code (VS Code), Agile
The most amazing...
...project I've worked on is a transactional-based content management system used for dynamic user interface generation and front tier for the banking industry.
Work Experience
Architect and Senior Full-stack Developer
Bee There Care
- Engineered the architecture of both back- and front-end applications, ensuring scalability, reliability, and performance to meet the demands of a social platform for parents.
- Set up development and production environments, optimizing workflow efficiency and facilitating seamless deployment processes.
- Implemented payment modules and integrated Stripe, enabling secure and efficient payment processing for eCommerce transactions within the platform.
- Developed an eCommerce platform within the application, empowering users to buy childcare-related products and services and enhancing user engagement and monetization opportunities.
- Leveraged Strapi as a headless content management system, enabling flexible content creation and management while maintaining the separation of concerns between the front and back ends.
- Built a robust front end using React and Material UI, delivering intuitive and visually appealing user interfaces that enhance user experience and engagement.
- Utilized AWS Cognito for customer authentication, ensuring secure access control and user management functionalities within the application.
- Conducted thorough testing and optimization to ensure high performance and responsiveness across different devices and screen sizes.
- Collaborated closely with stakeholders to understand requirements and translate them into technical solutions that meet business objectives and user needs.
- Provided technical leadership and guidance to the development team, fostering a collaborative and innovative work environment.
Front-end React Developer (via Toptal)
InPerSuit, Inc.
- Selected the appropriate technology stack meticulously, ensuring seamless alignment with project requirements, and significantly contributed to the application's success.
- Played a pivotal role in architecting the framework, resulting in a robust and scalable front-end structure that laid the foundation for the entire project's success.
- Contributed actively to the creation of numerous reusable components, streamlining development efforts and promoting code reusability across the application.
- Took charge of code reviews, demonstrating a keen eye for detail and commitment to maintaining high code quality standards, resulting in fewer bugs and improved overall codebase reliability.
- Leveraged React Hooks and Context API to enhance component reusability and state management, improving developer efficiency and code maintainability.
- Collaborated closely with UI/UX designers to translate design mockups and wireframes into interactive and visually appealing user interfaces, ensuring a seamless user experience.
- Implemented responsive design principles using CSS media queries and flexbox/grid layouts, ensuring optimal performance across various devices and screen sizes.
- Participated actively in sprint planning meetings and provided accurate estimations for task completion, contributing to the efficient delivery of project milestones.
- Acted as a mentor to junior developers, providing guidance on React best practices and assisting in their professional development journey.
Senior Full-stack Developer
Mitivate
- Spearheaded the setup of the back-end architecture and project infrastructure, ensuring the scalability and reliability of the application.
- Implemented DevOps pipelines and AWS deployment strategies, automating deployment processes and enhancing development workflow efficiency.
- Established the front-end architecture, leveraging best practices and design patterns to create a modular and maintainable codebase.
- Created reusable components for the application using React and Material UI, promoting code reusability and accelerating development cycles.
- Collaborated closely with designers to translate Figma designs into functional front-end components, ensuring pixel-perfect implementation and alignment with design specifications.
- Improved the web application's performance by optimizing code, implementing lazy loading techniques, and minimizing network requests, resulting in a 30% reduction in page load times.
- Conducted code reviews, providing constructive feedback to maintain code quality standards and enhance overall codebase reliability.
- Mentored junior developers, sharing knowledge and best practices to foster their professional growth and development.
- Implemented monitoring and logging solutions, ensuring visibility into application performance and troubleshooting issues proactively.
- Participated actively in agile ceremonies such as sprint planning, stand-ups, and retrospectives, contributing to the continuous improvement of team processes and practices.
React Developer
nXlvl Inc. (Toptal Project)
- Spearheaded the setup of the project structure and architecture, configuring all application layers, including React, Apollo Client, React Query, Formic, and MUI, ensuring a robust and scalable foundation.
- Led the front-end development efforts for a cutting-edge NFT marketplace tailored for sports talents, implementing innovative features and intuitive user interfaces to enhance user engagement and experience.
- Reviewed team members' pull requests and provided constructive feedback to maintain code quality and adherence to best practices, fostering a collaborative and supportive team environment.
- Participated actively in backlog grooming meetings and Jira task estimations, contributing valuable insights to prioritize feature development and ensure alignment with project timelines and objectives.
- Leveraged React Query to optimize data fetching and caching, enhancing application performance and responsiveness.
- Collaborated with designers to translate Figma mockups and wireframes into interactive and visually appealing user interfaces, ensuring seamless integration of design elements and functionality.
- Implemented authentication and authorization mechanisms using Apollo Client and OAuth 2.0, ensuring secure access control and protection of user data.
- Demonstrated proficiency in agile methodologies, consistently delivering high-quality code increments in iterative development cycles to meet project milestones and deadlines.
- Conducted knowledge-sharing sessions to disseminate best practices and emerging technologies within the team, fostering continuous learning and professional growth.
Managing Partner and Development Manager
Iteraflow
- Conducted comprehensive requirements analysis and project definition sessions, ensuring alignment with client objectives and expectations.
- Designed and implemented highly redundant, secure, and scalable infrastructure architectures, utilizing cloud-based solutions and industry best practices.
- Established secure communication channels between front- and back-end systems, leveraging the OAuth 2.0 authorization protocol to safeguard data integrity and user privacy.
- Integrated with 3rd-party systems such as FreshBooks and Office 365, facilitating seamless data exchange and enhancing workflow automation capabilities.
- Led the performance testing and optimization efforts for Angular components and DOM activities, identifying and resolving performance bottlenecks to improve application responsiveness and user experience.
- Managed cross-functional teams to ensure timely project delivery and alignment with business objectives, fostering collaboration and accountability across departments.
- Established quality assurance processes and conducted regular code reviews to maintain code quality and minimize defects, improving product reliability and customer satisfaction.
- Provided technical guidance and mentorship to team members, fostering professional growth and skill development within the organization.
- Collaborated with stakeholders to define product roadmaps and prioritize feature development, ensuring alignment with market trends and customer needs.
Senior React Developer
Median Inc
- Established a robust front-end project environment by creating a React app, configuring necessary libraries, and structuring the project for scalability and maintainability.
- Architected and implemented the project's overall architecture, leveraging Redux for state management and Material UI for consistent and responsive user interface design.
- Engineered secure communication channels between the front- and back-end systems, implementing encryption protocols and authentication mechanisms to safeguard sensitive data.
- Integrated front-end components with back-end APIs, ensuring seamless data flow and synchronization between client and server.
- Developed reusable React components and UI patterns to streamline development efforts and maintain consistency across the application.
- Implemented unit and integration tests using Jest and React Testing Library, ensuring code reliability and preventing regressions in functionality.
- Optimized front-end performance by identifying and resolving performance bottlenecks, resulting in a 20% improvement in page load times.
- Collaborated with cross-functional teams to refine project requirements and prioritize feature development, ensuring alignment with business objectives and user needs.
- Mentored junior developers on React best practices, code quality standards, and software engineering principles, fostering a culture of continuous learning and improvement within the team.
Senior Front-end Developer
Most Investments, LLC d/b/a Pantheon Software
- Migrated a legacy Angular application to React using Redux and TypeScript, improving code maintainability and developer productivity.
- Designed and implemented the application's architecture, ensuring scalability, maintainability, and security.
- Orchestrated server-side communication implementations, optimizing data exchange processes and enhancing application performance.
- Implemented robust application security measures, including authentication and authorization protocols, safeguarding sensitive data and ensuring compliance with industry standards.
- Monitored other developers' work, providing guidance and feedback to maintain code quality and stability.
- Managed code complexity by implementing efficient design patterns and modular code structures, enhancing code maintainability and readability.
- Participated actively in sprint planning and retrospectives, contributing insights to improve development processes and team collaboration.
- Conducted knowledge-sharing sessions to disseminate best practices and emerging technologies within the team, fostering continuous learning and professional growth.
Angular and React Developer
Most Investments, LLC Pantheon Software
- Engineered an Angular 10-based web application for a caregiving NGO, enhancing user accessibility and streamlining information dissemination.
- Played a pivotal role in the architecture and development of a React-based application for coaching within the caregiving sector, optimizing user experience and fostering engagement.
- Developed a React web application tailored for caregivers, incorporating intuitive user interfaces and responsive design principles to facilitate ease of use and accessibility.
- Leveraged Redux and TypeScript to enhance state management and code maintainability, resulting in a 30% reduction in bug occurrences.
- Integrated REST APIs into front-end applications to enable seamless data retrieval and manipulation, enhancing application functionality and user experience.
- Employed CSS and HTML5 best practices to create visually appealing and responsive web interfaces, driving user engagement and satisfaction.
- Implemented back-end functionalities and established seamless communication between a Node.js server and the React front end, ensuring efficient data flow and system interoperability.
Technical Manager
Balkan Financial Services
- Spearheaded comprehensive research into banking architecture and technology, driving strategic decision-making and project execution to enhance operational efficiency and competitiveness within Balkan Financial Services.
- Pioneered the development of a cutting-edge web-based framework facilitating seamless communication between Oracle FLEXCUBE and diverse web applications, streamlining banking processes and improving customer interactions.
- Orchestrated a talented team in designing, developing, and successfully implementing three distinct web-based projects seamlessly integrated into the operational frameworks of prominent financial institutions in Bulgaria and Macedonia.
- Led deployment activities, database administration, and ongoing support for the Oracle FLEXCUBE Corporate Module, ensuring the reliability and performance of critical banking systems in alignment with regulatory standards and business objectives.
- Executed strategic projects and orchestrated seamless integration processes between FLEXCUBE and external systems, optimizing operational workflows and enhancing overall system interoperability.
Developer
Folio3 Software
- Spearheaded the server-side development of a dynamic virtual world catering to children's entertainment, showcased on Secretbuilders.com, ensuring seamless functionality and engaging user experiences.
- Engineered a robust web application leveraging Java EE technologies, optimizing performance and scalability to meet evolving business needs and user demands.
- Designed and implemented a SmartFoxServer extension using Java SE, enhancing real-time communication capabilities and fostering immersive interactive environments.
- Managed end-to-end development and maintenance of the PostgreSQL database server, implementing efficient data management strategies and ensuring data integrity and security.
- Collaborated with cross-functional teams to troubleshoot and resolve complex technical issues, ensuring uninterrupted operation of critical systems and applications.
- Demonstrated versatility and proficiency in a diverse tech stack, including Java SE, Java EE, JavaScript, CSS, and PostgreSQL, adapting quickly to new technologies and project requirements.
Experience
Value-based Healthcare Reimbursement Platform
Closely collaborating with a committed team of 10 individuals, encompassing the CEO, project manager, and technical experts, I undertook a transformative 2-year endeavor to pioneer this innovative solution. Operating entirely remotely, our team exerted unwavering effort to realize the company's mission, adeptly navigating the dynamic landscape of the healthcare sector.
Child Care Social Platform
https://beethere.careAt its heart, BeeThere cultivates "Circles of Trust," connecting parents within communities to coordinate childcare arrangements seamlessly. Through intuitive features like a shared calendar and a point-based exchange system, BeeThere facilitates efficient childcare management, allowing parents to prioritize quality time with their children.
Built with cutting-edge technologies, including Node.js, Express, MongoDB, React, Next.js, and Material UI, BeeThere offers a seamless user experience, blending robust back-end functionality with an intuitive front-end interface.
Embodying the essence of inter-neighborly cooperation, BeeThere empowers communities to come together and support one another in the fulfilling journey of parenthood.
Business Credit Builder Platform
https://www.equiire.comAs a back-end developer, my responsibility involves architecting and implementing core functionalities to ensure a seamless user experience. Leveraging MongoDB for data management, I handled intricacies, guaranteeing integrity and scalability. Integrating Stripe for payment processing, I prioritized secure transmission and robust error handling. Security measures, including encryption and access controls, fortify user data protection. Challenges like scalability are met through cloud-based infrastructure and containerization technologies. Real-time updates on payment statuses are facilitated using WebSockets for enhanced user transparency.
In conclusion, my contributions have been vital in crafting a sophisticated platform empowering businesses to streamline credit-building processes and unlock growth potentials.
Mobile Only Bank App
At its core, the system comprises a dynamic web application with OAuth 2 authentication and a suite of microservices housing intricate business logic. Built on a robust RESTful architecture using Java 8 and Spring Boot, the framework ensures agility and scalability.
As the architect and principal developer, I was responsible for:
• Crafting the architecture and conceptual design for a seamless user experience.
• Fortifying the system's security through rigorous mechanisms.
• Spearheading RESTful API design for seamless mobile integration.
• Conducting performance testing and optimization for efficiency.
• Resolving bugs and overseeing code reviews to ensure reliability.
This project sets a new standard in mobile banking, merging innovation with user-centric design to reshape the digital finance landscape.
Nonprofit Project Management SaaS Solution
As the lead front-end developer, I had the following responsibilities:
• Analysis of requirements and project scope definition.
• Design and implementation of core AngularJS models, services, and components.
• Architectural decisions and implementation of the security and communication layers with the server.
• Authentication and communication with Office 365 using Adal.js and single sign-on architecture.
• Performance testing and optimization of AngularJS components and DOM activities.
• Maintaining quality and best practices.
Appliance Repair Franchising Solution
As a lead developer, I was involved in the following:
• Architectural decisions and implementation of the core modules in the system.
• Securing the communication between JavaScript clients and a web server using OAuth 2 and AngilarJS.
• Design and development of reusable AngularJS models, services, and components.
• Performance testing and optimization in different layers, including server scalability, HTTP(S) data transfer, data rendering, and JavaScript execution speed.
Internet Banking Solution
As the software architect and consultant, I was involved in the following:
• Architectural decisions and implementation of the core modules in the system.
• Securing the communication between JavaScript clients and a web server using OAuth 2 and AngilarJS.
• Design and development of reusable AngularJS models, services, and components.
• Performance testing and optimization in different layers, including server scalability, HTTP(S) data transfer, data rendering, and JavaScript execution speed.
Bank Front Office System
As a software architect and lead developer, I collaborated closely with database administrators, the card department, and front office managers to define the highly flexible architecture and seamless workflow.
Transaction-based Content Management System
As the architect and lead developer, I oversaw the execution of the project and integration process with FLEXCUBE and other external systems.
Business Reporting System
As an architect and lead developer, I oversaw the architecture and development of the system. Under my leadership, the project was integrated into two banks, where it serves as the management and operational reporting platform.
Document Management System
As the architect and lead developer, I was involved in the following:
• Analysis of requirements, project scope definition, and communication with the client.
• Architecture and development of server-side components and database communication layer.
• Design and development of client-side components, visualization, and security layers for server communication.
• Performance testing and optimization.
Quality Control Platform
As part of a global, remote team, I collaborated closely with the Head of Product to align development with strategic goals. Using Next.js, React, and TypeScript, I designed and implemented new features, optimized the back end with Prisma ORM and Aurora Postgres, and ensured scalable deployments via AWS and Vercel. My role included full-stack development, proactively addressing challenges, and contributing to the platform's stability and efficiency. By building features from the ground up and improving lifecycle processes, I helped deliver a robust, user-friendly solution that enhances supply chain quality management.
Education
Master's Degree in Technology Entrepreneurship
Sofia University St. Kliment Ohridski - Sofia, Bulgaria
Bachelor's Degree in Mathematics and Informatics Science
Sofia University St. Kliment Ohridski - Sofia, Bulgaria
High School Diploma in Mathematics and Informatics
Mathematical Gymnasium - Pleven, Bulgaria
Skills
Libraries/APIs
React, Node.js, JAX-RS, jQuery, REST APIs, React Query, React Router, Zod, React Redux, Stripe, Formik, React Hook Form, Amazon API, Recharts, Stripe API, Auth0 API, Dwolla API, Apollo Client, Java Servlets
Tools
Git, Jira, Mongoose, Spring Tool Suite (STS), Apache Maven, Subversion (SVN), Apache JMeter, React Apollo, Figma, JavaScript Testing, JSS, AWS IAM, Amazon Cognito, Stripe Checkout, Yarn Workspaces, Auth0, Elastic, Amazon Simple Email Service (SES), FullCalendar, MailerLite, FreshBooks, Prisma
Languages
HTML, CSS, TypeScript, JavaScript, SQL, Java, Java 8, HTML5, ECMAScript (ES6), Java SE, CSS3, Sass, GraphQL, SCSS, Markdown, C++
Frameworks
Redux, Spring Boot, JUnit, Spring, Spring MVC, OAuth 2, AngularJS, Angular, Swagger, Next.js, Express.js, Material UI, WebApp, Tailwind CSS, Bootstrap, Jersey, React Native, MJML
Paradigms
Responsive Web Design (RWD), REST, Mobile Development, Agile Software Development, Agile, Scrum, Search Engine Optimization (SEO)
Platforms
Visual Studio Code (VS Code), Java EE, Blockchain, AWS Elastic Beanstalk, MacOS, Amazon Web Services (AWS), Oracle Database, AWS Lambda, Azure, Heroku, Docker, Vercel
Storage
PostgreSQL, MySQL, Oracle SQL, NoSQL, Microsoft SQL Server, MongoDB, Alibaba Cloud
Industry Expertise
Healthcare
Other
DocumentDB, User Interface (UI), Responsive Web Apps, Front-end, Front-end Development, Architecture, APIs, Mobile First, Front-end Architecture, Front-end Design, Software Engineering, Software Architecture, Responsive UI, Webhooks, Full-stack Development, Web App Development, Full-stack, Digital Payments, API Integration, User Experience (UX), Technical Leadership, CTO, React Server Components, MERN Stack, Security, Minimum Viable Product (MVP), Server-side Rendering (SSR), Single Sign-on (SSO), OAuth, Solution Architecture, Back-end, Web Development, CSS-in-JS, Single-page Applications (SPAs), Performance Optimization, Mobile Apps, CI/CD Pipelines, Cloud Platforms, Monorepos, TSS, Strapi, eCommerce, TanStack Query, Stripe Subscriptions, DocuSign, Dashboards, WebSockets, Apollo, Video Players, Web Applications, PDF, Startups
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