Senior AI Full-Stack Developer

Senior AI Full-Stack Developer or Established Dev Team for a Long-Term Collaboration We're looking for a highly experienced freelance full-stack developer or a well-coordinated two-person team to help us build and grow our AI software platform at ScaleUp Systems over the long term. We're building our own advanced AI Setter — a system that communicates with potential customers over social media, understands conversation context, qualifies leads, follows up intelligently, and helps turn conversations into qualified appointments and new clients. To get a sense of the kind of platform we're building, search for "Mochi" (themochi) — you'll find it right away. That's a good reference point for the level we're aiming at. What matters most to us: design and aesthetics Our product needs to be strong on the backend — but it also has to feel premium. We don't want a tool that merely works; we want one people genuinely enjoy using and that feels high-end. For that we need someone with a real sense for modern UI and UX design — someone who doesn't just build what we ask for, but proactively brings their own ideas to the table, ideas that actually impress us. Honestly: we've often had the experience of someone saying "I can do that" — and only finding out far too late that they couldn't. We want to avoid that from the start this time. So: - Send us references where you did the design completely end-to-end yourself — where nobody else handled the visual side. Screenshots, live demos, links — whatever shows it best. - Be open to a small test project. Small and manageable, but enough for us to see up front whether it's really a fit. That's fairer for both sides. Two ways this collaboration can work We're open to two setups — just apply for the one that fits you: Option 1 – Solo: A developer who can do both: excellent design and a strong backend for the software we're building. Someone who builds new things independently instead of only executing predefined tasks. A good reference point for the level we mean is Mochi (see above). Option 2 – Team: A well-coordinated two-person team made up of a very, very strong backend developer and a strong designer. What matters is that you're genuinely used to working together and can deliver at the highest level as a pair. Innovative AI development We don't want a simple chatbot that just forwards every message to a single AI model. Our goal is an intelligent AI Setter that recognizes conversation phases and intent, factors in the relevant information, qualifies leads individually, and makes sensible decisions depending on the situation — at a quality that doesn't exist yet in this form. We'll develop that further together with you. For that we're looking for a partner who genuinely understands modern AI systems, contributes their own technical ideas, and works independently toward a defined end result — without someone having to spell out every single development step. The goal is enough for us; you plan and execute the path to it yourself. And not as an MVP, but done so well that we're genuinely impressed. What's especially important to us: - A strong sense for modern UI and UX design, and for a premium product feel - Extensive experience with AI applications and intelligent chatbots - Experience with large language models, AI agents, memory systems, and context management - Strong skills in modern full-stack development - Experience with scalable backends, databases, and complex API integrations - Working independently and actively bringing in your own ideas and improvements Experience with TypeScript, Next.js, Node.js, Fastify, PostgreSQL, and Redis is especially relevant for our project. Meta API Experience with the Meta API is a big plus, especially in: - Instagram Messaging and Direct Messages - Instagram comments - Meta Webhooks - OAuth - Instagram Business Accounts - Meta Permissions and App Review Even without direct Meta API experience, a collaboration can be interesting if you have extensive experience with complex APIs and get up to speed on new systems quickly. Scope of the collaboration We're looking for people who want to work with us long term — on an hourly basis as a freelancer. The scope is roughly 30–40 hours per week. We're open to fully remote collaboration. What to send us directly in your application: 1. Your hourly rate in euros — tell us directly in your application what you have in mind. 2. 2–5 relevant references (as screenshots, links, live demos, or GitHub). Ideally projects from our space or something similar. If a project has nothing to do with ours, briefly explain why it's still relevant. 3. Concrete examples of why you're a strong fit for our project. For each reference, briefly: - What was built? - What was your specific role? - Which technologies were used? - Which parts did you build yourself (especially the design)? 4. Proof that you can build a product yourself — not just an LLM with a prompt wrapped around it, but something genuinely independent with real quality. 5. Proof that you can work independently toward a predefined goal — without needing tasks broken down into small steps. We prefer a short, direct exchange over a long formal application. Just apply here through Upwork with your name and a note that you're reaching out about the AI Developer project — after your message we'll set up a short intro call. We're looking for a long-term partner who works independently, takes ownership, and wants to build a genuinely innovative AI platform together with us.