Senior Full Stack Engineer - Ai Voice Platform

About VoiceBWe build autonomous AI voice agents that close and qualify sales for large B2C enterprises - telcos, energy providers, insurers, banks. Our agents already run live inside companies like Vodafone España and Holaluz, and we’re mid-rollout across an 8-market European deployment with Alpega/Teleroute. We’re a small team moving fast, and we’re building the commercial engine to match the product.The roleWe’re looking for a senior full stack engineer to join a small, high-ownership engineering team building the core VoiceB platform - the systems behind SuperVoice, SuperQualification, Memory, and our outcome tracking. This is a remote role for someone based in Spain, working closely with our CTO and the rest of engineering.What you’ll doBuild and ship features across the platform: backend services, APIs, third-party integrations (Salesforce, HubSpot, Twilio, SIP/WebRTC), and internal toolingOwn features end to end - design, build, test, deploy, monitorPartner directly with the CTO and founders on architecture decisions as the platform scalesContribute to security and compliance hardening for enterprise clientsWhat we’re looking for4+ years of full stack experience, comfortable owning features end to end on a small, fast-moving teamStrong in a modern JS/TS stack (React/Node or similar); comfortable with cloud infrastructure (AWS/GCP)Based in Spain, fully remote, able to overlap with Barcelona working hoursProduct-minded - you care about what gets built, not just howNice to haveExperience with real-time or telephony systems (SIP, WebRTC, Twilio)Experience integrating LLMs or other AI/voice tooling into production systemsEarly-stage startup experienceWhat we offerCompetitive salary + equityFully remote (Spain-based)Direct influence over the architecture of a product still being definedWe’re hiring deliberately, not urgently - we’d rather find the right person than fill the seat fast. If this sounds like your kind of problem, we’d love to hear from you.

4+ years of full stack experience, comfortable owning features end to end on a small, fast-moving team Strong in a modern JS/TS stack (React/Node or similar); comfortable with cloud infrastructure (AWS/GCP) Based in Spain, fully remote, able to overlap with Barcelona working hours Product-minded - you care about what gets built, not just how Nice to have Experience with real-time or telephony systems (SIP, WebRTC, Twilio) Experience integrating LLMs or other AI/voice tooling into production systems Early-stage startup experience

Competitive salary + equity Fully remote (Spain-based) Direct influence over the architecture of a product still being defined We’re hiring deliberately, not urgently - we’d rather find the right person than fill the seat fast. If this sounds like your kind of problem, we’d love to hear from you.

About VoiceB We build autonomous AI voice agents that close and qualify sales for large B2C enterprises - telcos, energy providers, insurers, banks. Our agents already run live inside companies like Vodafone España and Holaluz, and we’re mid-rollout across an 8-market European deployment with Alpega/Teleroute. We’re a small team moving fast, and we’re building the commercial engine to match the product.