Senior Software Engineer - AI Hub

About Us:

OfficeRnD has one mission - making flexible and hybrid working a norm rather than an option!

We started building our SaaS platform back in 2015 to support the future of work. We believe that having freedom and flexibility is the way to provide better workspace experience. And that’s what enables us to develop products that matter - for our customers and for the world.

The company has offices in Bulgaria, USA, UK, Australia, and our teammates are the ones getting us to the top in our market niche.

So if you live and breathe technology as well, come and join us!

About the Role:

We're seeking a Senior Software Engineer to join our Bulgaria-based engineering team. You'll be a core part of the newly launched AI Hub — our dedicated AI automation layer within OfficeRnD Flex. The AI Hub is redefining how flexible workspace operators run their businesses, starting with our first autonomous agent: the AI Sales Agent.

This is a backend-heavy role where you'll design and build the high-performance systems and backend infrastructure that power these intelligent workflows. Front-end work exists but is not the focus. What matters here is deep backend thinking, clean API design, and the ability to bridge the gap between core business logic and cutting-edge AI orchestration, while delivering reliable software in fast iterations. If you're a software engineer genuinely curious about diving deep into production-grade AI engineering and autonomous agents, this is a strong fit.

What You'll Do:

• Design, build, and scale the backend architecture and APIs powering the AI Hub and its autonomous agents (like the AI Sales Agent).
• Implement robust, low-latency integrations between core backend systems, LLMs, and communication channels to support 24/7 real-time automation.
• Ensure consistency, performance, and correctness across high-volume data models and complex backend workflows.
• Own MongoDB schema design and query optimization for complex data structures (including data models optimized for AI context and conversation history).
• Collaborate closely with Product Managers, Software Architects, and AI specialists to translate advanced automation requirements into robust technical solutions.
• Own and lead backend-focused strategic initiatives and architectural improvements within the AI Hub ecosystem.
• Own and lead frontend-focused strategic initiatives and architectural improvements within the AI Hub ecosystem.
• Debug and resolve production issues across the backend stack and infrastructure layer.
• Review peer code with a focus on correctness, performance, and maintainability.
• Write unit and integration tests and functional tests; 
• Mentor junior engineers on backend fundamentals, system design, and AI integration best practices.
  

What You'll Bring:

• 5+ years of backend engineering experience in cloud-based, production environments.
• Proficiency in at least one server-side technology (Node.js, Java, or .NET).
• Hands-on experience integrating LLMs or building AI-driven features in production - and genuine curiosity about where autonomous agents are heading.
• Experience designing AI agent architectures - tool/function calling, multi-step reasoning, memory/context management, and observability.
• Strong foundation in API design, distributed systems, and real-time data processing
• Experience with MongoDB schema design and query optimization; familiarity with vector DBs or caching strategies for AI is a plus.
• Extensive knowledge of software design principles - you default to clean architecture, separation of concerns, and domain modelling.

What We Offer:

• Premium health insurance, including dental coverage
• 25 days of annual paid leave
• An additional day off to celebrate your birthday
• 3 paid volunteering days per year
• Full compensation for the first 3 days of sick leave
• Hybrid work model (minimum 40% of monthly working time onsite)
• Co-funded sports card to support your active lifestyle
• Excellent learning and development opportunities, including access to courses, tools, and internal workshops focused on AI and modern engineering.
• To ease your commute, we provide you with either parking access or a public transport pass.

If this sounds like the right opportunity for you, we'd love to talk!