I will design your software architecture and be your fractional cto

C
crystaliumhr
C
crystaliumhr
Antun N.
design your software architecture and be your fractional cto
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design your software architecture and be your fractional cto

About this gig

  • Are you building a product and need senior-level technical guidance without hiring a full-time CTO? I can help.

I'm a full-stack software architect with 10+ years of experience, having worked with companies like Nike and Philips. I specialize in designing scalable systems, selecting the right tech stack, and providing CTO-level strategic direction.


What I offer:

  • Software architecture design (microservices, monolith, serverless)
  • - Tech stack selection and evaluation
  • - System design for scalability, performance, and security
  • - Code architecture review and refactoring guidance
  • - Cloud infrastructure planning (AWS, serverless, Lambda)
  • - Technical roadmap and engineering team guidance
  • - Startup CTO consultation - from idea to production

My stack: Node.js, TypeScript, React, Next.js, AWS, PostgreSQL, Redis, Docker


Whether you're a startup founder, product manager, or engineering lead - I'll help you make the right technical decisions from the start and avoid costly mistakes down the road.


Let's talk about your project.

  • Programming language

    • JavaScript
    • Python
    • TypeScript

  • Expertise

    • Algorithms & Data structures
    • Performance
    • Security
    • Databases

  • Frontend framework

    • Next.js
    • React.js

  • Backend framework

    • Express.js
    • NestJS
    • Node.js

Get to know Antun N.

Antun N.

Full Stack Developer and AI Expert

  • FromCroatia
  • Member sinceJun 2026
  • Avg. response time1 hour

  • Languages

    English
I am a full-stack developer and founder of Crystalium, a software agency based in Sibenik, Croatia. With 10+ years of experience, I build custom web applications, e-commerce platforms, and AI-powered tools for clients across Croatia and the EU. My stack includes Next.js, React, TypeScript, Node.js, Python, and PostgreSQL. I specialize in web development, AI integration (OpenAI, Anthropic, LangChain), and custom software solutions. I take pride in clean code, clear communication, and delivering real results.

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