AI Backend Engineer, Nexus

ITS Poland; Warszawa; Hybrid; PLN 180,000 - 340,000; Full time

Job summary

ITS Poland is looking for a backend engineer to contribute to reliable production AI systems using Python 3.12+, FastAPI, asyncio, WebSocket and REST APIs. Experience with gRPC is a plus. The role spans LLM integrations across AWS Bedrock, Claude/OpenAI, Gemini/Vertex AI and streaming APIs.

The focus is on tooling, RAG, prompt engineering, context enrichment, and external API integrations, with strong emphasis on scalable infrastructure, testing, and deployment in Docker/Kubernetes environments.

Qualifications

• Backend: Python 3.12+, FastAPI, asyncio, WebSocket, and REST APIs. gRPC is a plus.

Skills

Backend development

LLM integrations

AI tooling

ML/LLM fundamentals

Quality and infrastructure

Real-time audio streaming

Tools

Docker

CI/CD

AWS

Kubernetes/Helm

gRPC

REST APIs

WebSocket

AWS Bedrock

Anthropic Claude API

OpenAI API

Google Gemini API

Vertex AI

Job description

• Backend: Python 3.12+, FastAPI, asyncio, WebSocket, and REST APIs. Experience with gRPC is a plus.
• LLM integrations: AWS Bedrock experience is required; or/and familiarity with Anthropic Claude API, OpenAI API, and Google Gemini API, Vertex AI, etc. Experience with streaming APIs, tool/function calling, and multi-step agent workflows.
• AI tooling: RAG, MCP, prompt engineering, context enrichment, conversation history management, and external API integrations.
• ML/LLM fundamentals: At least basic nderstanding of transformers architecture and attention mechanisms, tokenization, embeddings, context windows, and data pipeline fundamentals.
• Quality and infrastructure: Automated testing, mocking external services, LLM evaluations and guardrails; Docker, CI/CD, AWS, and basic familiarity with Kubernetes/Helm.
• Nice to have: Real-time audio streaming, Gemini Live, ElevenLabs TTS/STT, AWS Connect, DynamoDB, MQTT, and IoT integrations.
• The role focuses on reliable production AI systems, not training models from scratch.

Alternative Language Backgrounds:

• Python is our primary implementation language, but prior Python expertise is not a strict requirement. We also welcome strong engineers whose main background is in:
• C++ – systems engineering, concurrency, networking, and performance.
• Go – backend services, cloud infrastructure, and gRPC.
• Java / Kotlin – production backend systems and service integrations.
• C# / .NET – asynchronous APIs and cloud applications.
• Rust – systems programming, asynchronous networking, and reliability.