Founding Software Engineer

On-siteSalary not specified
France · United Kingdom

Tech Stack

Problem Solving

Job Description, Responsibilities & Requirements

About the Position

At The Flex, we believe renting a home should be as effortless as booking a ride. Our mission is ambitious: enable anyone to live anywhere, anytime, without friction.

Powered by Base360.ai, our proprietary technology platform, we are building the operating system for modern renting-automating operations, connecting fragmented systems, and creating seamless experiences for guests, landlords, and operators across the world.

We're looking for a Founding Software Engineer to help architect and build the technology that powers the future of The Flex. This is not a typical engineering role. You'll work directly with the founder, influence product strategy, make architectural decisions, and build systems that become the foundation of a global business.

You'll have extraordinary ownership, responsibility, and impact from day one.

What You'll Build

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

From AI-powered workflows and booking systems to operational automation and intelligent decision-making, you'll build products that directly impact revenue, efficiency, and customer experience.

You won't just ship features. You'll create systems that replace manual work, unlock scale, and become a competitive advantage for the company.

Responsibilities

  • Build Core Products: Design, build, and launch the software that powers bookings, pricing, payments, operations, communications, and guest experiences.
  • Architect the Platform: Make key technical decisions and help define the long-term architecture of Base360.ai.
  • Create Automation at Scale: Develop workflows and systems that automate operational processes across multiple countries and thousands of stays.
  • Leverage AI: Build AI-powered tools, agents, and workflows that improve productivity, decision-making, and customer experience.
  • Integrate the Ecosystem: Develop and maintain integrations with platforms including Airbnb, Hostaway, Stripe, Twilio, Google, OpenAI, and other strategic partners.
  • Move Fast: Operate with urgency and ownership, turning ideas into production-ready solutions quickly and effectively.
  • Solve Real Problems: Work on challenges such as reservation synchronization, dynamic pricing, smart access management, guest communication automation, operational forecasting, maintenance and cleaning automation, AI-powered alerts and monitoring, and revenue optimization.
  • Help Build the Company: As one of the first engineers, your influence will extend beyond code. You'll help shape processes, culture, product direction, and the future engineering team.

Tech Stack

Our current stack includes:

  • Python
  • FastAPI
  • React
  • TypeScript
  • Supabase
  • PostgreSQL
  • AWS
  • OpenAI APIs
  • Stripe
  • Twilio
  • Docker
  • GitHub Actions

We care more about your ability to learn and build than your experience with any specific technology.

Requirements

Must Have

  • Strong software engineering fundamentals
  • Experience building production-grade applications
  • Strong understanding of APIs, databases, and system design
  • Product mindset and customer obsession
  • Ability to work independently with minimal supervision
  • Strong problem-solving ability
  • High level of ownership and accountability

Bonus Points

  • Startup experience
  • Experience with AI products or LLM integrations
  • Experience building SaaS products
  • Experience with FastAPI, React, AWS, or Supabase
  • Marketplace, travel, or PropTech experience

This Role Is Not For You If

  • You're looking for a predictable corporate environment
  • You prefer maintaining systems rather than building them
  • You need constant direction and supervision
  • You avoid ownership outside your immediate responsibilities
  • You are uncomfortable with change, ambiguity, and rapid execution

We Offer

  • Massive Impact: Your work will directly shape how thousands of people live, travel, and experience cities.
  • Founding-Level Ownership: You'll have significant influence over product, technology, and company direction.
  • Build Alongside the Founder: Work closely with leadership and help define the future of the business.
  • Learn Faster: Gain exposure to engineering, AI, product, operations, growth, and company-building.
  • Performance-Based Rewards: Competitive compensation with meaningful upside for exceptional contributors.
  • Remote-First: Work from anywhere. We care about results, not hours.

About the Company

At The Flex, we are revolutionizing the way people rent homes. Our mission is to make renting as seamless and effortless as booking a ride. By leveraging our proprietary technology platform, Base360.ai, we aim to automate operations, connect fragmented systems, and create seamless experiences for guests, landlords, and operators worldwide.

Join us in building the operating system for modern renting and help us create a global business that impacts thousands of lives.

Job Details

Location:
France · United Kingdom
Employment Type:
Full-time
Work Mode:
On-site
Posted on TheJob:
Jul 13, 2026
Last checked:
Jul 13, 2026
Posted on the source:
Jun 16, 2026
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