Khalvai Ozbek
Khalvai Ozbek open to work
Kaiserslautern, Rheinland-Pfalz, Germany

I prioritize doing things right over doing things fast and love building systems for long-term usage,
making them understandable for future engineers.

TypeScript NestJS Node.js PostgreSQL DDD Hexagonal Arch. Docker

// how I think about hierarchies

Layered system architecture diagram Concentric rectangles showing infrastructure wrapping application wrapping domain, with ports connecting the domain to the outside world. INFRASTRUCTURE HTTP · gRPC · DB · Queue APPLICATION use cases · orchestration DOMAIN business logic · rules the core stays pure port port
Simplicity over cleverness
Passionate for learning about software
Build for the people who maintain it next

Experience

Where I've worked

Where I've worked, what I built, and how I grew.

  • Apr 2025 – Mar 2026  ·  1 year

    Senior Software Engineer

    Intelika.ai

    AI services company building LLM-powered conversational experiences for enterprise customers.

    • Migrated from a Microservice to a modular monolithic architecture, reducing development time and complexity.
    • Interviewed and onboarded 4 Software Engineers into the team.
    • Documented the adopted principles and recorded videos explaining the concepts adapted by the team.
    • Mentored 2 interns, supporting their growth and successful integration into the development team.
    NestJS TypeScript Modular Monolith DDD Team Leadership
  • Mar 2024 – Apr 2025  ·  1 year 2 months

    Software Engineer

    Intelika.ai

    AI services company building LLM-powered conversational experiences for enterprise customers.

    • Built an internal NestJS seedwork adopted across multiple microservices, standardising architecture and reducing onboarding effort.
    • Decoupled HTTP and gRPC communication protocols from business logic, making domain code more understandable and independently testable.
    • Discovered business bounded contexts and integrated domain model concepts into the existing N-Layered Architecture.
    NestJS TypeScript DDD gRPC Microservices
  • Apr 2023 – Feb 2024  ·  11 months

    Software Engineer – Digital Menu

    Digital Menu

    Digital Menu is a platform for creating and managing digital menus for restaurants and cafes.

    • Implemented the inbox/outbox pattern, ensuring eventual consistency and idempotency of events.
    • Dockerized the project with separate test, development, and production stages, improving development experience.
    • Removed unnecessary abstractions tied to implementation details, making the codebase simpler and more maintainable.
    NestJS TypeScript Inbox/Outbox Docker Event-Driven
  • May 2022 – Apr 2023  ·  1 year

    Backend Engineer

    Nobati.app

    Appointment management platform offering tailored scheduling solutions for businesses, serving over 200,000 users.

    • Migrated JavaScript codebase into TypeScript, using DDD, separating concepts in smaller chunks.
    • Planned parallel development of old repositories and integration with new services.
    • Contributed to the success of a company serving over 200,000 users by prioritizing solving existing challenges.
    • Solved payment problems and issuing subscriptions for the users, making a flow of purchase
    • Solved concurrency issue of reserving a slot of time for a user, using two level locks in the business process.
    NestJS TypeScript Hexagonal Arch. CQRS DDD
  • Oct 2021 – Mar 2022  ·  6 months

    Backend Developer

    Asrez Group

    Web technology consultancy delivering creative software infrastructure solutions to clients.

    • Developed APIs using REST and GraphQL to support diverse client applications.
    • Implemented an N-layered architecture in NestJS, ensuring scalability, testability, and clear separation of concerns.
    NestJS TypeScript REST GraphQL

Talks

On stage

Conference talks and university workshops on architecture, patterns, and developer craft.

  • Poster for "Software Architecture and Hidden Costs"

    28 Dec 2024  ·  FullstacksJS YouTube Channel

    Software Architecture and Hidden Costs

    Trade-offs and how to avoid long-term architectural costs.

    watch seminar →
  • Poster for "Software Architecture"

    20 May 2024  ·  Vali-e-Asr University

    Software Architecture

    The importance and history of software architecture — from monoliths to modern distributed systems.

  • Poster for "Design Patterns"

    22 Apr 2024  ·  Vali-e-Asr University

    Design Patterns

    The importance of patterns with live demonstrations of real-world applications.

  • Poster for "Clean Code Principles"

    9 Feb 2023  ·  Vali-e-Asr University

    Clean Code Principles

    Clean code principles explained with annotated code samples and live refactoring.

Contact

Get in touch

You also care about patterns and architecture?
I'm open to discuss, feel free to contact me.