Java Software Engineer

● Led a team of 3 Java developers and built from scratch, as the main contributor, the backend of a national construction licensing platform for the Ministry of Construction. The platform replaced the manual work of an 11-person ministry department and serves 2,000+ companies, 15,000+ experts and 1,000+ daily users. ● Cut expert qualification review from ~2 weeks to 1 day by moving diploma and employment-record checks, exam booking and certificate issuing online. Added QR codes to every license and certificate for public verification. ● Automated license compliance with nightly reconciliation against the tax service and the company registry: work types are suspended once a company's certified experts leave, and company renames sync automatically. ● Integrated the national government data exchange (built on Estonia's X-Road) in both directions, national single sign-on (OAuth2 with PKCE) and a payment gateway, with a full audit trail of every license operation. ● Architected the backend of an AI fatigue-monitoring system for air traffic controllers, piloted at Manas International Airport: 16 consoles, 23,000+ readings/day, Face ID-based work sessions, role-based alerts with escalation and worked-hours export to payroll. ● Designed the RabbitMQ contract with the AI team so no event is lost or double-counted (idempotency keys, ack after DB commit, dead-letter queue); fixed live camera feeds freezing for concurrent viewers with a stream fan-out proxy. ● Took over as project lead of a legacy Java EE border-zone permit system shared by 3 government agencies. Cut processing for foreign tourists from ~2 weeks to ~2 days across 50,000+ applications/year with an online application API for the national e-services portal. ● Stopped production OutOfMemory crashes by fixing a Cartesian-product JOIN in the shared repository layer and a database connection leak in report generation.

● Designed and implemented a high-load traffic analysis service processing 28GB/day of compressed BRAS logs (200M rows/day), enabling identification of top external sites and supporting strategic decisions to integrate select sites into a Content Delivery Network (CDN). ● Developed an automated TV box replacement service within the billing system, handling 6,000 monthly requests (200/day), reducing back-office workload by 80%. Created a comprehensive knowledge base to streamline future operations. ● Diagnosed and resolved a physical network switch port availability issue in the Userside platform, which falsely indicated ports were occupied, blocking new subscriber connections. Replaced a manual process (6,000 updates/month per employee) with an automated service, processing 18,000 records in 2 hours, increasing efficiency by 90% and enabling seamless subscriber onboarding. ● Built a pirated content detection service for online cinemas using Levenshtein Distance, Jaro-Winkler Distance, and Jaccard Similarity algorithms to detect exact and approximate title matches. Identified over 500 pirated titles, generating actionable reports for rights holders. ● Developed a content title parser for partner online cinemas, aggregating over 100,000 titles from diverse sources. Enabled accurate comparison of reported versus actual content volumes, uncovering discrepancies and enhancing partner accountability. ● Created a service to track employee attendance statistics using RusGuard controllers for the new office ● Contributed to migrating network services to a Kubernetes cluster, containerizing applications and supporting CI/CD pipeline implementation in GitLab, reducing deployment time by 50% across 10+ services. ● Conducted comparative analysis of ELK and Grafana Loki, implementing Loki as the optimal logging solution for scalability, reducing critical issue detection time in production from 1 hour to 2–5 minutes, enhancing system reliability. ● Developed a company car booking module, reducing request time from 15 to 3 minutes by displaying available drivers and shifts, eliminating manual calls, and introducing a reporting system for 1000+ monthly bookings. ● Built a birthday tracking module for 500+ employees in the HR system, automating daily checks and personalized email greetings, improving corporate culture based on positive employee feedback.