Senior AI-Native Full-Stack Engineer — LLM & AI Workflows

Poland and Middle-Eastern Europe; United States; Remote; USD 140,000 - 190,000; Full time

Job summary

Xebia is seeking a Senior Fullstack Engineer to join a small, focused product team building an AI-powered accounting platform. You will own features end-to-end—from a conversational idea, through the API and data model, to what the customer sees and trusts.

You will develop backend services and integrations with accounting systems and design reliable AI-powered workflows using LLMs, tool calling, and streaming.

Qualifications

• Minimum 6 years of commercial experience in fullstack software development.
• Backend: Node.js + Express, strong command of TypeScript.
• Frontend: React and Next.js (SSR/SSG, App Router).
• Designing and building REST APIs; GraphQL a plus.
• PostgreSQL - data modeling and query optimization.
• Testing: unit and integration tests (Jest/Vitest).
• CI/CD and containerization (Docker).
• Experience with the cloud (AWS / GCP / Azure).
• Hands-on AI/LLM production experience: LLM APIs, tool calling, streaming, prompting, or agent workflows.
• AI-native: daily work with AI development tools (Cursor, GitHub Copilot, Claude Code).
• Ability to verify, debug, and refactor AI-generated code.

Responsibilities

• Own features end-to-end — from idea in a conversation to API, data model, and customer view.
• Develop backend services and integrations with accounting systems.
• Design and ship reliable AI-powered workflows (LLM APIs, tool calling, streaming, agent flows).
• Improve reliability, performance, and keep the codebase healthy.
• Collaborate with product, engineering, and domain experts to bring ideas to customers.

Skills

Fullstack development

Backend architecture decisions

AI/LLM production experience

Unit/integration testing

CI/CD

Cloud experience

Security and reliability

Tools

Node.js

Express

React

Next.js

REST APIs

GraphQL

PostgreSQL

Docker

AWS

GCP

Azure

Jest/Vitest

TypeScript

CI/CD

Kubernetes

Cursor

GitHub Copilot

Claude Code

Job description

Xebia is seeking a Senior Fullstack Engineer to join a small, focused product team building an AI-powered accounting platform. You will own features end-to-end—from a conversational idea, through the API and data model, to what the customer sees and trusts.

You will develop backend services and integrations with accounting systems and design reliable AI-powered workflows using LLMs, tool calling, and streaming.