Role: Senior / Principal Software Engineer
Job Type: Full-Time
Contract Type: Direct employment with our client
Location: Hybrid – Barcelona
Language: Fluent Spanish is required
Visa sponsorship is not available for this role
[Only interested in speaking with candidates who are comfortable working in a hybrid model]
They are now looking for a Senior/ Principal Software Engineer to help scale the platform behind their voice agents, owning features end-to-end across their TypeScript / Python stack and working on AI pipelines, LLM orchestration, STT/TTS, prompt workflows and real-time systems.
5 years of production experience with modern web stack
~ Production experience with TypeScript, JavaScript, Python or C#
~ Experience with AI coding agents such as Claude Code,



Cursor or Codex
~ Comfortable with Docker, SQL, testing and scalable architecture
~ Fluent Spanish

AWS/GCP, CI/CD and observability experience
Startup or early-stage product company experience
Developing product features end-to-end with React, TypeScript and AI infrastructure
Improving architecture, observability, testing and engineering quality
Working directly with the founders and senior team to shape the platform
Concentric Recruitment is a boutique recruitment firm focused primarly on recruitment for Cloud, DevOps and AI Engineering roles.

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