Founding Full-Stack Ai Native Engineer (€60K-€80K) React/Python - €60.000 - €80.000 A Year

Ai Hiring Startup; Barcelona; Híbrido; EUR 60.000 - 80.000; Jornada completa

Ventajas ofrecidas por este puesto de trabajo

Stock options

First engineering hire

Hybrid in Barcelona

Hybrid work model

Descripción de la vacante

Ai Hiring Startup in Barcelona is seeking a skilled Full-Stack Engineer to help build an AI-native platform with Next.js frontend and FastAPI backend. You will join as the first engineering hire and shape architecture, tooling, and deployment patterns in a hybrid Barcelona setting.

The role emphasizes shipping fast with observability, AI agent integrations, and robust HR-tech connections. 3 days in office with founders, 2 remote days, and stock options are offered.

Formación

• 4+ years professional software engineering (full-stack).
• Proven ability to ship features end-to-end (Next.js + Python / FastAPI preferred).
• Experience with AI agents and LLM APIs.
• Experience with monorepos, deployment automation, CI/CD, and Docker.

Responsabilidades

• Ship features rapidly, end-to-end from frontend to backend.
• Design and implement integration patterns with HR tech stacks.
• Set up monitoring and deployment automation for safe releases.

Conocimientos

Full-stack engineering

Ship features end-to-end

Next.js

Python

FastAPI

AI agent experience

Herramientas

Next.js

FastAPI

Docker

CI/CD

Descripción del empleo

We're building an AI-native platform with autonomous agents, smart workflows, and real-time voice interactions. Looking for a Full-Stack Engineer. Salary : €60k-€80k Hybrid : BCN 3 Days, Remote : 2 Days.

Team : of 3 co-founders now. 6 by the end of the year. You will be our 1st employee!

LONG VERSION

Key Information

Who are we? We're a SaaS AI hiring startup, founded in October 2025.

What are we aiming for? To offer a simple, unique, and differentiated solution that addresses some of the recruiter’s most painful problems.

What drives / obsesses us? One of the founders has +20 years of recruiting experience, founded and, and has tested every ATS on the market — he’ll be a heavy daily user.

Product : AI Interviews / Agents + Omnichannel / All-In-One : WhatsApp + LinkedIn + Email. We’ll be the first to launch something key in the fast detection of talent.

Market : Primarily the US, but global from day one.

Customers : ICP : We are going Enterprise & Mid market (High Volume Recruiting)

Product : will be extremely simple : only the features that solve the recruiter’s biggest pains.

Risks : Like in any startup, they exist, and we’ll explain them during the interview.

Founding team : : / / : / / : Well-funded with 2 years of runway. Investors : +10 successful entrepreneurs with exits in their projects.

Goal 2026 : full focus on acquiring customers.

Tech & Challenges

1. Ship Features Fast, Build Platform as You GoDesign and ship end-to-end features (Next.Js frontend → FastAPI backend → Supabase)Identify when manual deploys / testing / monitoring hurt, automate them.Create reusable patterns for common integration needs (data-access, webhooks, auth, data sync)You'll ship the feature this week, automate the deployment next week, extract patterns the month after.
2. Integration Architecture for HR Tech StackDesign API patterns that work for ATS, HRIS,, LinkedIn, email providers, and future integrations.Build webhook handlers, auth flows (OAuth, JWT), data sync pipelines.Make integrations testable, observable, and resilient from day one. Monitoring and self-healing is critical.Think about how to "eat" external providers when appropriate.
3. Safe Deployment & MonitoringSet up monitoring / tracing for every feature you ship (know what breaks and where)Create deployment automation as manual deployment pain increases.Build internal tooling to make deployments safe, routine, and low-friction.Know when to ask for help setting up observability, then automate it for next time

You Are

• 4+ years professional software engineering (full-stack)
• Proven ability to ship features end-to-end (Next.Js + Python / FastAPI preferred)
• Experience and excitement towards AI Agents (coding agents, LLM APIs)
• Experience with monorepos, deployment automation, CI / CD, Docker.
• Strong API, webhook, and authentication pattern knowledge (OAuth, JWT)
• Balance pragmatism and perfection - ship fast, know what's imperfect, fix systematically.

AI / LLM proficiency is required : You are a heavy user of AI coding agents (Claude, Cursor, GitHub Copilot, or similar) and LLMs in your daily workflow. AI-assisted development is not optional - it will be expected and enforced.

Ownership mindset : You own features from first commit to production monitoring.You automate when manual work becomes painful, not before.You ask for help setting up observability when needed, then automate it.You identify where things need monitoring and either set it up or escal…

We test for : Can you ship a feature AND identify where it needs monitoring?
When you encounter friction (deploys, testing, integration), do you automate or accept it?
Can you collaborate with founders on technical decisions while still moving fast?
Do you think in systems - how does this feature connect to everything else?

Nice to Have

• Prior experience at pre-Series A startups ( HR / ATS integration experience (merge.Dev,, manatal, Greenhouse, Lever, etc.)
• AI / ML integration patterns (LLM agents, voice tech)
• Platform engineering or internal tooling experience.
• Experience building developer tools or documentation systems.

We Offer

• Salary : €60k-€80k
• Optional Stock Options Plan (we’ll explain them during the interview)
• Impact : First engineering hire beyond founders - define how we build software, set patterns, shape culture.
• Work model : Barcelona, Flexible Hybrid. 3 days in office with founders preferred. We're not remote-first - physical proximity in early stages creates better products and faster iteration.
• Environment : Zero politics, zero micromanagement, near-zero meetings. Private penthouse office (not co-working), focused work environment.

The role

You’ll be the multiplier that makes our entire team faster. xhfqzwm Ship features, build the platform as you go, and help us create a tech organization built on leverage.