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# Founding Software Engineer

- **Company:** The Flex
- **Location:** Spain
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Artificial Intelligence, Amazon Web Services, Cloud Engineering, Distributed Systems, Github, Python (Programming Language), Key Management, PostgreSQL, Systems Integration, Twilio, TypeScript, ReactJS, Backend, Fastapi, Event Driven Architecture, Stripe, Operational Systems, Marketplace, Serverless Computing, Docker
- **Published:** August 15, 2026
- **Apply:** https://www.jobleads.com/es/job/e3eb6651c5d02d213e35dd0b577595cf5

## About the Role

* Strong experience building production-grade software systems
 * Experience with FastAPI, Python, React, or similar frameworks
 * Strong understanding of APIs, distributed systems, and cloud architecture
 * Experience designing scalable backend systems
 * Ability to work independently with minimal supervision
 * Strong problem-solving ability and product mindset
 * Curiosity about AI, automation, and operational efficiency
 * A bias toward action and shipping

Bonus Points For Experience With

 * Property technology (PropTech)
 * Marketplace businesses
 * AI agents and workflow automation
 * Event-driven architectures
 * Supabase
 * AWS serverless infrastructure, * You're looking for a slow-paced corporate environment
 * You prefer maintaining systems rather than building them
 * You need detailed instructions for every task
 * You avoid ownership and accountability
 * "Good enough" is your standard

## Description

As a Founding Software Engineer, you'll help architect and scale Base360.ai-the technology platform powering every aspect of The Flex.

You'll build internal products, automation engines, AI-powered workflows, integrations, and operational systems that eliminate manual work and allow the business to scale globally.

Your work will touch everything from guest journeys and property operations to pricing intelligence and AI-driven decision-making., Design and develop scalable applications, services, and APIs that power bookings, pricing, payments, guest experiences, and operations., Create robust APIs that enable seamless communication between internal systems, third-party providers, and future products., * Real-time reservation synchronization

 * Dynamic pricing intelligence
 * Smart key management
 * Automated guest communication
 * Operational forecasting
 * Cleaning and maintenance automation
 * AI-powered monitoring and alerts, We care more about capability than specific technologies, but our current stack includes:
 * Python
 * FastAPI
 * React
 * TypeScript
 * Supabase
 * PostgreSQL
 * AWS
 * Serverless Architecture
 * OpenAI APIs
 * Twilio
 * Stripe
 * Docker
 * GitHub Actions


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