● Developed from scratch (initial stages as a principal developer, then assembled a team of 2 additional developers) an application using Nest.js (microservices architecture for a project related to IoT). ● Implemented performance monitoring and optimized critical business components through Redis caching and MongoDB indexing. ● Utilized Kafka Connect. ● Established a business process logging system. Enhanced the existing CI/CD system. ● Result: The product achieved approximately 100 times faster performance compared to the previous generation + stability and full compliance with specifications were achieved. ● In other projects: Created a video streaming project from scratch (similar stack with microservices and websockets, RTCDataChannel, Kafka, stream recording via ffmpeg, etc.), continued project development by forming a team of 2 developers while remaining in the role of tech lead and developer.

● Wrote from scratch several new fullstack apps related to employee management for industrial plants. Backend: Node.js, TypeScript, frontend: React.js, TypeScript, database: PostgreSQL. Result: new products ready to be sold to new and existing B2B‑customers. ● Developed and integrated a logging system for all existing apps. Result: real‑time analysis of performance. ● Containerized into Docker several legacy apps.

● Developed a full‑stack white‑labeled dashboard. Backend: Node.js, Express.js, Python. Frontend: React.js / Next.js. Databases: PostgreSQL, triggers. Orchestration: Nginx, Docker. Wrote modules for integration of the dashboard with external websites, developed a standardized API for such interaction. Challenge: developed an ORM with dynamic complexity of resulting queries. Frontend: developed a visual interface to build queries of arbitrary complexity. ● Soft skills: wrote deployment instructions and taught a junior DevOps engineer to deploy the dashboard on new servers. Cloud virtual servers (Hetzner), caching/DDoS protection (CloudFlare), GoDaddy (hosting). ● Soft skills: regularly presented the developed product to B2B‑customers, discussed development of new features. ● Result: new fully functional product ready to be sold to customers.

● Wrote a casino (iGaming) framework from scratch (several gaming providers, payment providers). Go (Golang), Express.js, React.js. New product with immediate profit. ● Developed analytics dashboards for the marketing department. Back‑end: Node.js, Express.js. Front‑end: Pug. Database: MongoDB. Integration with the company’s central database, with front‑end analytics scripts. Wrote business‑specific user tracking scripts. Result: huge savings for the company due to better analytics of the website and its traffic. ● Deployed a mass mailing system, integrated via its API various services of the company. Automated creation of personalized email messages: started storing customers’ new aggregated parameters, created scripts for building personalized images on the fly to be used in email messages. Result: +50% profit for the company due to a new customers’ loyalty system.

● 2013: Created a chat bot, published the code on Github. ● 2018: Created a "bridge" app connecting various messengers so that each other the community could use any messenger they like and still talk to people from other messengers, published the code on Github. ● 2021: Created lojban.pw static website (open-sourced) using React.js, Next.js, Tailwind CSS, Webpack and various self-written compilation scripts, published code on GitHub. ● 2022: Using PEG grammar, various graph visualization libraries built a simple app displaying syntax trees of the Loglan language. ● 2022: Compiled a text-to-speech app in Python. ● 2022: Created a sample Nest.js project to be used as a boilerplate.

● Wrote from scratch a complete mass mailing system with personalization, triggers, generation of personalized e‑mail messages for the online shop. Stack: Node.js, MySQL. Result: up to 10% more profit per month for the company due to boost of the incoming traffic. ● Wrote analytics scripts for the department of marketing. Stack: Node.js, MySQL. Helped marketing and financial specialists automate their Excel reports using VBA.