Senior Software Engineer

About PubNub

PubNub powers the world’s most engaging real-time experiences—chat, live updates, and interactive applications—for over 2,000 companies including Verizon, Autodesk, Zillow, and Dropbox. Our global data network processes trillions of messages each month with sub-100 ms latency across 15+ data centers. Backed by $130M in funding, we’re shaping the future of how the world connects.

We’re now building something new: an intelligence layer that lets developers weave large language models (LLMs) and deep-learning pipelines directly into high-speed streams. We believe AI should be as real-time as the data it reasons about, and we’re hiring founding engineers to make that vision real.

About the Role

We are looking for a Senior AI Engineer to design and operate AI systems that run in real time and at high scale. You will join a focused AI team responsible for building production-grade AI features and shared infrastructure that enables other engineering teams to deploy AI safely and efficiently. This role is remote-first within Poland, with the option to work from our Katowice office if you prefer.

Responsibilities 

• Design, build, and maintain AI-powered services integrated into PubNub’s platform
• Architect low-latency ML and LLM pipelines processing millions of messages per minute
• Build internal frameworks, APIs, and tooling for AI feature adoption
• Train, fine-tune, and operate models in production
• Develop and maintain infrastructure for running LLMs at scale
• Extend existing backend and client systems to support AI features
• Collaborate with product and engineering teams on system design and trade-offs
• Improve developer experience through clean APIs, SDKs, and documentation

About you

Must Have

• 5+ years of software engineering experience
• 1+ year of hands-on experience with AI/ML systems in production
• Experience shipping customer-facing AI features
• Experience deploying and scaling LLMs in production
• Experience working with high-throughput systems (millions of messages/minute)
• Strong knowledge of TypeScript, Python, or Rust
• Solid system design and backend development skills
• Regular use of AI-assisted development tools (Copilot, Cursor, Claude, etc.)
• Fluent English

Nice to Have

• Real-time or streaming systems (Kafka, Kinesis, WebSockets)
• Developer platforms, SDKs, or internal tooling
• Cloud AI platforms (AWS Bedrock, Azure OpenAI, Vertex AI)
• Docker, Kubernetes, infrastructure as code
• Model serving frameworks (TorchServe, MLflow, TensorRT)
• Vector databases and embedding-based systems

Why Join PubNub

• Build a greenfield intelligence platform at internet scale
• Ship features that land directly in customer-facing products across healthcare, fintech, gaming, and streamingAbout the Role
• High ownership and influence over technical decisions
• Remote-first setup within Poland
• Competitive B2B compensation ranging between PLN26,000 - PLN32,000 per month
• Open paid time off
• Stock options
• Optional office in central Katowice

If you’re excited to make AI real-time, we’d love to hear from you.