Full Stack Engineer

Pillar; Lombardia; On-site; EUR 55,000 - 75,000; Full time

Job summary

Pillar is seeking a product-minded Full Stack Engineer with a backend emphasis to help us scale our AI-driven financial operating system for construction. You will own features end to end, work across Next.js/React/TypeScript, and deepen backend architecture while maintaining the full product picture.

We value hands-on ownership, fast iteration in small squads, and comfort with AI-native workflows. Location options include Milan or Barcelona, with English proficiency and Italian/Spanish language

Qualifications

• Hands-on product engineer with backend depth.
• Startup/scaleup experience and ownership mindset.
• Italian or Spanish native with professional English.

Responsibilities

• Own features end to end from problem to production.
• Build across TypeScript stack: Next.js, React, Supabase, Node/Deno, Postgres.
• Own backend logic, data models, APIs and architecture.
• Collaborate in small squads with autonomy and fast decision making.
• Apply AI as a native part of engineering workflow.

Skills

Backend depth

Full stack

Next.js

React

TypeScript

AI-native mindset

Tools

Supabase

Mastra

Postgres

Node/Deno

Job description

Pillar was founded in 2025. Today, we are 80+ people, serve 900+ customers, raised €12 million in 2026, and are expanding internationally.

We are building the financial operating system for construction: bringing AI, automation, and modern software to an enormous industry still full of slow, fragmented processes.

We are looking for a product-minded Full Stack Engineer who leans backend, moves fast, and wants to build.

The mission

Build product end to end, with particular strength on backend architecture and execution. Our frontend capability is already strong; we now want someone who can deepen the team on backend while still owning the full product picture.

What you will do

• Own features end to end, from product problem to production.
• Build across our TypeScript codebase using Next.js, React, Supabase, Node/Deno, Postgres, and Mastra.
• Take strong ownership of backend logic, data models, APIs, integrations, and product architecture.
• Work hands-on on the frontend when needed, with a strong preference for engineers comfortable with Next.js.
• Use AI as a native part of your engineering workflow - not only as a feature you build.
• Work in small squads with high autonomy and bottom-up initiatives.
• Move quickly from ambiguity to working product, making pragmatic technical decisions along the way.
• Raise the engineering bar through collaboration, judgment, and execution.

Our stack

• AI: Mastra · AI-native workflows

Who we are looking for

Product engineers with backend depth and high agency

• You are a product engineer: you build outcomes, not just code.
• You are stronger on backend or genuinely full stack. Pure frontend profiles are not our priority for this hire.
• You are comfortable with Next.js, React, TypeScript, and modern backend/data patterns. Supabase experience is a strong plus.
• You have worked in a startup or scaleup environment and understand the pace, ambiguity, and ownership it requires.
• You take initiative, get your hands dirty, and get things done without waiting for perfect instructions.
• You are AI-native: AI is already part of how you think, build, debug, learn, and move faster.
• You can zoom out to understand the full picture and zoom in when details matter.
• You learn from failure, communicate openly, and collaborate without ego.
• Native Italian or Spanish is mandatory, together with professional working English.

How we work

• Agile and squad-based: small teams own their domains, with no unnecessary layers.
• AI-first: we build and work in the age of AI.
• Full-stack ownership: engineers are hands-on and accountable for delivered value.
• Bottom-up: initiative is expected, not delegated.

The profile that can succeed

Backend-leaning · Product-minded · Startup DNA

The sweet spot: a hands-on product engineer from a startup/scaleup journey, ideally around the €3M-€30M growth stage, with backend depth and enough frontend fluency to own features end to end.

Location & languages

Milan or Barcelona; native Italian or Spanish (mandatory) plus professional English.

What we offer

• Gross salary 55,000-75,000 €
• The opportunity to build core parts of Pillar’s product and engineering foundations as we scale
• End-to-end ownership: from product decisions and architecture to shipping features used by real customers.
• The chance to work in an AI-native engineering team, where AI is part of both the product and the way we build it.
• Close collaboration with Product, AI, and Engineering, with direct exposure to the problems we are solving for customers.
• Real autonomy, responsibility, and room to grow as Pillar and the engineering team scale.