Dmitrii Frolov

A real-time voice agent kids talk and play with to practice spoken English.

• Built and own the agent harness behind the AI tutor — the integration layer between the real-time voice model and the product. It exposes UI-driving tools to the model, feeds it live student actions, and manages the conversation flow, so the model plays the game with the child instead of just talking. Kept it model-agnostic, migrating the agent across live models without disrupting production.
• Built monitoring that automatically detects conflicts in the AI's assembled instructions, combining rule-based checks with a second model acting as a judge, so bad configurations are caught before they reach live lessons.
• Made the activity system configuration-driven — designed the content model and data contracts so new scenarios, goals, and prompts ship as data in the CMS instead of code, letting non-engineers launch activities without a release.

A MarTech & e-commerce SaaS platform for web forms, promo widgets, and email marketing.

• Built a full email marketing toolkit including a campaign builder, editor, and integrations with third-party services, reducing time-to-launch for new email campaigns from days to minutes.
• Designed and implemented an onboarding flow for new users, improving early user engagement and reducing churn during the first week after signup.
• Integrated A/B testing into the platform, including feature flags and experiment tracking, enabling data-driven optimization of CTAs and onboarding flows that improved conversions.
• Redesigned the platform dashboard, improving navigation architecture so users can reach any feature within 3 clicks, reducing time-to-feature and improving overall product usability.
• Introduced structured code review process and automated linting standards, cutting release cycle from monthly to weekly and reducing post-release regressions below 5%.

A Travel & Hospitality SaaS booking platform for hotels, flights, and events, built on Next.js.

• Reduced Total Blocking Time by 80% (4.2s → 0.84s) and eliminated Cumulative Layout Shift through Next.js SSR pipeline optimization, raising Lighthouse performance score by 33 points.
• Built the component library using Tailwind CSS and Storybook with 100% auto-generated documentation coverage, streamlining design-engineering collaboration.
• Integrated Lighthouse checks into CI/CD with automated reports, enabling continuous performance monitoring and early regression detection before production.
• Delivered features end-to-end as a fullstack engineer, handling both frontend and backend implementation independently using Node.js and NestJS.

A MarTech & e-commerce SaaS platform for web forms and promo widgets.

• Migrated legacy AngularJS codebase to React and RTK using Single-SPA micro-frontend architecture, refactoring the codebase and reducing Total Blocking Time (TBT) by 60%.
• Built a statistics dashboard with geo-charts and time series visualizations using Google Charts.
• Migrated authentication from session cookies to JWT tokens, reducing server load and enabling instant dashboard access without page reloads, improving login experience.
• Added click-to-configure interaction to the WYSIWYG editor, allowing users to access any widget element's settings with a single click, significantly improving editing speed.
• Optimized Webpack build pipeline through bundle splitting, tree shaking, and dependency cleanup, reducing build time by 60% and improving developer experience.
• Built an integrations layer connecting the platform with third-party email marketing services via webhooks, enabling real-time data sync between the platform and external tools.
• Redesigned the token system and style architecture, enabling pixel-perfect component development across the platform.

An EdTech online platform for kids with real-time video lessons and interactive whiteboard.

• Acted as tech lead and mentor for a micro-team of 3 engineers, delivering the MVP in 4 months and establishing the technical foundation for the entire platform.
• Researched and integrated the open-source media server Kurento, enabling WebRTC-based video calls in the browser and accelerating the launch of the first product version.
• Designed and built a real-time video communication platform using WebRTC and Node.js from scratch, scaling to 1000+ concurrent active sessions per day.
• Built a real-time collaborative whiteboard with multi-user interaction, animations, and visual effects, powered by WebSockets for instant cross-participant synchronization.
• Built a self-diagnostic tool that checks users' camera, microphone, and connection quality before video lessons, reducing lesson cancellations by 40% and improving session reliability.
• Set up Jenkins CI/CD pipeline with multi-environment staging stands deployed on AWS EC2, automating builds and deployments and eliminating manual release steps.
• Integrated Lokalise for i18n automation, reducing translation preparation time for new features by 3x.
• Grew into Tech Lead role, doubled the engineering team, established development processes and code review standards that cut the release cycle from monthly to weekly.

A Telecom SaaS platform for cloud storage, serving major mobile operators including Vodafone.

• Designed a deeply customizable frontend architecture for the company's core product Cloudike, used by millions of users across multiple operators.
• Built web and mobile clients from the ground up, including an SSO client for seamless authentication across all platforms.
• Implemented i18n support for multiple languages across all operator markets.
• Ensured WCAG compliance across all platform interfaces for users with disabilities.