Senior AI Engineer

About Us
5Blue Software is an Israeli-Ukrainian software development company specializing in custom software development, staff augmentation, dedicated engineering teams, AI solutions, and CTO-as-a-Service. We help startups and mid-sized companies scale faster with vetted engineering talent across Europe.

About the Role
We are looking for a Senior AI Engineer to join one of our client projects — an early-stage US-based wellness AI startup. You will work as a fractional contributor, starting with a structured technical handoff from the outgoing engineering team, then transitioning into ongoing launch support and system maintenance. You will need to take real technical ownership, communicate clearly with the client, and hit the ground running with minimal onboarding from our side.

Requirements
7+ years of software engineering experience

Expert-level proficiency in AI/ML engineering

Excellent spoken and written English (C1) — direct client communication is required

5+ years working with LLMs — Claude, OpenAI, or equivalent — in production environments

Hands-on experience building agentic and multi-turn conversational systems

Strong prompt engineering skills — system prompts, structured outputs, context management, cost vs. quality tradeoffs

Experience with tool/function calling, memory layers, and RAG pipelines

Familiarity with LLM observability — logging, tracing agent steps, monitoring output quality

Understanding of prompt injection risks, output validation, and guardrails

Ability to get up to speed on an unfamiliar codebase quickly and document it clearly

Experience with messaging integrations will be a plus

Self-directed and comfortable taking ownership with minimal oversight

Does this position sound like a perfect match? We're eager to hear from you!