This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Machine Learning Engineer, Voice Agents based in Spain.

Own a major part of an open voice-agent stack at the intersection of machine learning, realtime systems, and developer infrastructure.
You will lead the architecture and evolution of an open-source speech-to-speech library while helping turn a new voice platform into a production-ready developer product.
The role combines deep backend and ML engineering with realtime audio, inference infrastructure, and developer experience.
You will integrate rapidly evolving ASR, TTS, and end-to-end speech models while maintaining clean abstractions and strong reliability.
You will have significant autonomy to shape APIs, streaming protocols, GPU serving, observability, and production architecture.
Your work will directly enable developers to build and deploy sophisticated voice agents and will support existing realtime deployments, including robotics applications.
This is an open,



highly collaborative environment where you can contribute publicly through documentation, demos, talks, and open-source development.

Accountabilities
- Take architectural ownership of significant parts of the open-source speech-to-speech library, including pipeline design, latency budgets, and realtime loop reliability.
- Integrate new ASR, TTS, and end-to-end speech models as they become available while maintaining clean, extensible abstractions.
- Review community contributions, triage issues, manage releases, and help grow the contributor community around the project.
- Design the developer API and streaming protocol for the voice platform, including session lifecycle, WebSockets/WebRTC transport, authentication, error semantics, and versioning.
- Build and operate the serving infrastructure for realtime GPU inference, including concurrency, autoscaling, observability, and cost-per-session optimization.
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📌 Senior Machine Learning Engineer, Voice Agents (Madrid)
🏢 Jobgether
📍 Madrid