Full-Stack Engineer, Co-founder (40k-60k + 10-20 Equity) AI Native / Voice Agents Startup React / NodeJS

We're building an AI-native platform with autonomous agents, smart workflows, and real-time voice interactions. Looking for Full-Stack Engineer who will join the co-founding team. When the tech team grows, you will become the CTO.Key Information : Who are we? We're a SaaS hiring startup, set to launch in September 2025.What are we aiming for? To offer a simple, unique, and differentiated solution that addresses some of the recruiter's most painful problems.What drives / obsesses us? One of the founders has +20 years of recruiting experience, founded Infojobs.net and Hireflix.com, and has tested every ATS on the market — he'll be a heavy daily user.Product : AI Interviews / Agents + Omnichannel / All-In-One : WhatsApp + LinkedIn + Email. We'll be the first to launch something key in the fast detection of talent.Market : Primarily the US, but global from day one.Customers : We are not going enterprise, this won't be a company with a sales team : CEO = Sales. The product will be extremely simple : only the features that solve the recruiter's biggest pains.Risks : Like in any startup, they exist, and we'll explain them during the interview.Founding team : + Funding : Well-funded with 2 years of runway. Investors : +10 successful entrepreneurs with exits in their projects.Goal : Reach break-even within 2 years. We don't plan to raise more rounds — full focus on acquiring customers.Tech & Challenges : Next.js (frontend, SSR)Python (backend, AI integrations)API integrations, LLM agents, voice tech.Designing autonomous, voice-driven workflows.Connecting external tools (CRMs, ATS, etc.)You Are : Full-stack (Must : 3+ yrs, Nice2Have : 5+)Product-driven, fast-moving, execution-focused.Not afraid to own tech, product, and early architecture.Excited by autonomy, speed, and building from zero.Have you been a co-founder? (Nice2Have) Drop me a DM ASAP.We Offer : Co-founder role : salary (40-60k) + meaningful equity (10-20% POSTRound)The final salary and equity will depend on several factors that we will explain during the interview.Hybrid, async-friendly, but both founders are 100% in-person and that's our preference. It's very hard to go from 0 to 1 : we prefer to be physically together (at least 3 days), maintaining extreme focus and avoiding interruptions. btw : we are open to talk.Office in Barcelona : Diagonal / Casanova. Top-floor penthouse with terrace. Private and very quiet office : We're NOT a co-working space, but we're on the same floor as other startups like Banktrack.Working hours? : If you're asking yourself this question, definitely don't apply. (This is a Co-founder role, with 10-20% Equity post 700k€ Round)Zero BS, Zero micromanagement, Near-Zero meetings.