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# Senior/Lead Full-stack Developerstartup

- **Company:** Haystack People
- **Location:** Zwanenburg, Netherlands
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** JavaScript (Programming Language), Application Programming Interfaces (APIs), Artificial Intelligence, DevOps, Python (Programming Language), Machine Learning, Node.Js, Next.js, System Testing, TypeScript, ReactJS, Large Language Models, GPT
- **Published:** October 27, 2026
- **Apply:** https://www.werk.nl/nl/vacatures/71957649

## About the Role

An experienced full-stack JavaScript developer with a focus on Node.js, as well as experience with React, Next.js, Typescript &JavaScript.
Experience and interest in Python and Machine Learning/AI are a significant plus.
Strong interest in infrastructure/devops...

## Description

As a Senior Full-Stack Developer at our client's company, you will be the key figure in shaping the structure of their APIs. This role goesbeyond regular development; you must have a deep understanding of system testing. Managing system tests is crucial because thesoftware must seamlessly integrate into customers' software.The software will enable any company to build its own AI version of software, much like a company can currently build a mobile version ofits software. This means even complex tasks can be executed effortlessly by Large Language Models (LLMs) like ChatGPT. In this role,you will work closely with the CTO to refine and expand the MVP to make the software suitable for enterprise environments.