Founding, Full Stack Engineer (React.js & Python)

Full Stack Engineer (React.js, TypeScript, Python) – YC AI Scale-up – Amsterdam, NL

Experience: 3+ years – React.js, TypeScript, Python
Employment type: Full‑Time

Job Overview

Our client develops AI sales employees for Europe. Their first product is an AI SDR that owns the entire outbound process – from researching relevant companies to executing campaigns on email, LinkedIn, and via letters. We are seeking a highly skilled and proactive founding software engineer to join our YC‑backed startup full‑time and in person in Amsterdam. This is a fantastic opportunity to make a substantial impact in a fast‑paced, early‑stage startup environment.

Responsibilities

• Own and develop core product features on both the frontend and backend.

• Collaborate with founders and customers to conceptualise, design and implement new features.

• Maintain and improve the codebase for optimal performance.

• Conduct code reviews and perform debugging tasks.

Required Qualifications

• Proven track record in full‑stack development, preferably as a Senior Software Engineer.

• Comprehensive knowledge of TypeScript, React, and server‑side development (preferably Remix).

• Proficiency in designing multi‑tenancy SaaS products.

• Experience leveraging latest AI code IDEs (Cursor, Windsurf, Claude, IntelliJ, Junie).

• Experience operating software in a scalable manner.

• Fluent in English; able to communicate complex technical concepts clearly and effectively.

Bonus Skills and Experience

• Proficiency in Python.

• Experience hosting applications on Azure.

Application

Submit a copy of your CV directly to this advertisement or email david@wearesyntera.com. This role is actively interviewing and can be offered within 7‑10 days.

Location

Amsterdam, North Holland, Netherlands – On‑site role.