Backend‑First Full‑Stack Engineer — AI & Payments

Pillar; Barcelona; On-site; EUR 65,000 - 80,000; Full time

Benefits offered by this job

Gross salary 65,000-80,000€

Real ownership of architecture and产品

AI-native team

Close to customers

Team that celebrates wins

Job summary

Pillar is hiring a backend-leaning Full Stack Engineer in Barcelona, onsite. You will own features end to end, shaping data models, APIs and integrations for payments and project finances, with a strong focus on backend architecture and scalable systems.

You will also contribute to frontend work in Next.js and React when needed, and apply AI to product building, debugging and learning, joining a small, autonomous squad in a fast-growing company.

Qualifications

• Experience building product in a startup or scaleup.
• Strong backend and databases; explain design decisions.
• Frontend fluency to own a feature end to end.

Responsibilities

• Own features end to end, from the customer problem to production.
• Design data models, APIs and integrations behind payments, invoices and project finances.
• Raise the bar on backend architecture across our TypeScript codebase.
• Work on the frontend in Next.js and React when the feature needs it.
• Use AI as a native part of how you build, debug and learn.

Skills

TypeScript

PostgreSQL

Next.js

React

Backend architecture

APIs design

Supabase

Tools

Supabase

Job description

Pillar is hiring a backend-leaning Full Stack Engineer in Barcelona, onsite. You will own features end to end, shaping data models, APIs and integrations for payments and project finances, with a strong focus on backend architecture and scalable systems.

You will also contribute to frontend work in Next.js and React when needed, and apply AI to product building, debugging and learning, joining a small, autonomous squad in a fast-growing company.