Senior AI Fullstack Engineer

Tappz GmbH; Warszawa; Remote; PLN 180,000 - 260,000; Full time

Job summary

Tappz GmbH is building AI-native applications and seeks an engineer focused on AI systems and agent development to join our fast-moving team. You will design and build backend systems powered by LLMs and ship AI features into production.

Ideal candidates have strong backend and frontend skills (Node.js, Next.js, Typescript, Python), experience with LLMs and AI APIs, and familiarity with vector databases and RAG workflows. This role offers a remote-friendly setup.

Qualifications

• Strong backend and frontend engineering experience with modern frameworks.
• Deep experience with LLMs and AI APIs.
• Experience building AI agents or multi-step workflows.
• Experience with vector databases (Pinecone, Weaviate, etc.).
• Experience with RAG implementations.
• Strong prompt engineering and system design skills.
• Production deployment experience.

Responsibilities

• Design and build backend systems powered by LLMs.
• Develop agent workflows and tool integrations.
• Build RAG pipelines with vector search.
• Handle prompt orchestration and context management.
• Optimize performance, latency, and cost.
• Ship AI features into production products.

Skills

Node.js

Next.js

Typescript

Python

Nest.js

GCP

LLMs & AI APIs

AI agents

Vector DB

RAG

Prompt engineering

System design

Production deployment

Job description

Tappz is building AI-native applications powered by large language models. We’re moving fast in a highly competitive space and need an engineer who is fully focused on AI systems and agent development.

We’re looking for someone who enjoys high ownership, working hard, and shipping real AI products.

Tasks

• Design and build backend systems powered by LLMs
• Develop agent workflows and tool integrations
• Build RAG pipelines with vector search
• Handle prompt orchestration and context management
• Optimize performance, latency, and cost
• Ship AI features into production products

Requirements

• Strong backend and frontend engineering (Node.js, Next.js, Typescript, Python, Nest.js, GCP)
• Deep experience working with LLMs and AI APIs
• Experience building AI agents or multi-step workflows
• Vector DB experience (Pinecone/Weaviate/etc.)
• RAG implementation experience
• Prompt engineering and system design
• Production deployment experience

Mindset we value: Ownership, speed, and the willingness to go the extra mile

High ownership in a fast-growing AI startup, remote-friendly setup, and the chance to build agent systems in production.