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Rubiboo

Founding Software Engineer · 💰 $40K–$60K USD

EU

September 24, 2026 at 7:22 AM

✨ AI summary

💰 $40K–$60K USD

Location

  • Spain (Remote)

Languages

  • Python
  • TypeScript

Frameworks

  • FastAPI
  • React

Cloud Services

  • Azure
  • Cloudflare

Databases

  • PostgreSQL

About the opportunity


We’re a headhunting firm focused on connecting exceptional talent with high-growth technology companies. We’re currently helping an early-stage startup (Convexity) hire their Founding Software Engineer — First Hire.


The company is building an AI-native ERP, with a team of ex-Microsoft, Apple, Wayfair, Columbia University, and Northeastern University talent, including published research in the space.


They’re already at multiple six figures in ARR, backed by top investors after just a few months, and have built an exceptional network of engineers, researchers, investors, customers, and operators.


As the first hire, you’ll work directly with the founders, write a lot of code, talk to customers, make important product decisions, and help define the company’s engineering culture from the ground up.


You’ll receive a strong salary and meaningful equity with significant upside.

What you’ll do

  • Own products end-to-end across frontend, backend, data, infrastructure, and AI.
  • Turn difficult operational problems into simple, reliable software.
  • Ship quickly while maintaining a high bar for correctness.
  • Work directly with customers and iterate based on real usage.
  • Help establish how the company builds, hires, and operates as it scales.


About you

  • High agency: you identify what matters and act without waiting for instructions.
  • Exceptionally smart, dedicated, ambitious, and eager to grow with the company.
  • Strong full-stack engineering skills, with experience in Python, React, TypeScript, APIs, and databases.
  • Comfortable moving quickly, navigating ambiguity, and owning outcomes rather than simply completing tickets.
  • Excited by AI agents, forecasting, optimization, ERP systems, and business operations.
  • Published research, exceptional technical projects, or other evidence of outstanding technical ability is a strong signal.


Tech stack

Python, FastAPI, PostgreSQL, React, TypeScript, AI agents, Docker, Azure, and Cloudflare.

Interested? Get in touch with Convexity and we can share more details about the company and opportunity.


Salary: $40K–$60K USD + meaningful equity.

Work mode: Fully remote