KK

Experience

Experience

3CX Ltd

3CX Ltd

Senior Software Developer · Nicosia, Cyprus

May 2022 — Present

3CX is a leading provider of VoIP PBX and unified communications solutions, trusted by 350k+ organizations in 190 countries for secure and reliable business telecommunications.

  • Key contributor in the AI team, focused on agentic capabilities for voice and chat. Work spans the full stack — management UIs, agent runtime logic, voice processing pipelines, provider orchestration, evaluation systems, and design system components.
  • Implemented fuzzy matching algorithms (Levenshtein distance, phonetic similarity) for contact search to improve lookup accuracy and robustness against speech recognition errors in voice agent interactions.
  • Reduced median call-state latency for real-time VoIP/WebRTC calls from ~250ms to ~120ms by re-architecting RxJS event pipelines, synchronizing heterogeneous data sources, and eliminating redundant emissions and memory leaks under high-load conditions.
  • Migrated 3CX LiveChat from Vue 2 to Vue 3 — drove adoption to 150k+ active installations via integrations across major CMS and e-commerce platforms.
  • Developed integrations with third-party VoIP providers, CRM systems, and AI services (speech transcription).
  • Contributed to the WebClient migration from AngularJS to Angular, improving maintainability and system performance.
  • Mentored junior developers through code reviews, onboarding, and technical guidance.
  • TypeScript
  • C# / .NET
  • OData
  • Angular
  • Vue
  • React / Next.js
  • Node.js
  • RxJS
  • WebRTC
  • VoIP / SIP
  • Voice AI
  • MCP
  • RAG / Vector Embeddings
  • REST
  • WebSockets
  • Protobuf / gRPC
NDA

NDA

Senior Software Engineer · Europe

Feb 2020 — May 2022

Industrial geospatial software development under NDA.

  • Core engineer in a small team responsible for designing and developing a large-scale geospatial 2D/3D visualization platform from the ground up through its first production release using React, Electron, CesiumJS, Resium, Three.js, MobX, Node.js, and SQLite.
  • Designed and implemented the project data layer connecting the React UI, SQLite project model, and 3D rendering engine, enabling project serialization, state hydration, import/export pipelines, terrain-aware geometry transformations, and synchronization of complex geospatial entities throughout the application lifecycle.
  • Optimized computational processing of complex geometries by implementing vertex simplification algorithms, reducing processed vertex counts while preserving visual accuracy and improving rendering performance by approximately 30%.
  • Developed REST- and WebSocket-based communication services enabling real-time synchronization and collaboration of geospatial entities between desktop clients and a geo data server.
  • Mentored two junior engineers through onboarding, code reviews, and technical guidance.
  • TypeScript
  • WebGL
  • CesiumJS
  • Resium
  • Three.js
  • React
  • Electron
  • Node.js
  • MobX
  • SQLite
  • WebSockets
  • REST
  • C#