Senior Software Engineer

Concentric Recruitment; Barcelona; Presencial; EUR 80.000 - 100.000; Jornada completa

Descripción de la vacante

Concentric Recruitment is seeking a Senior/Principal Software Engineer to join their team in Barcelona. This full-time role involves building scalable AI-driven communication products and requires strong expertise in TypeScript and Python.

The ideal candidate will have significant production experience and a solid understanding of modern web stacks. The position requires fluency in both Spanish and English and a willingness to work onsite five days a week.

Technical skills with Docker and SQL are also essential for this role.

Formación

• 5-7 years of production experience with modern web technologies.
• Experience with coding agents in AI.
• Ability to work autonomously with a real product mindset.

Responsabilidades

• Build scalable APIs and services for voice interactions.
• Develop product features using React, TypeScript and AI infrastructure.
• Integrate LLM, STT, and TTS workflows into production.

Conocimientos

Production experience with modern web stack

Experience with AI coding agents (Claude Code, Cursor, Codex)

Fluent in Spanish and English

Comfortable with Docker, SQL, testing and scalable architecture

Herramientas

Docker

SQL

React

Descripción del empleo

Role: Senior / Principal Software Engineer

Job Type: Full-Time

Salary range: to €100.000 + Equity

Contract type: Direct employment with our client

Location: Onsite in Barcelona

Only interested in speaking with candidates who are comfortable working from the office 5 days per week

Our partner is building next-generation AI-driven communication products that help businesses automate customer interactions, improve operational efficiency and generate actionable insights in real time.

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.

What we are looking for

• +5-7 years of production experience with modern web stack
• Experience with AI coding agents such as Claude Code, Cursor or Codex
• Real Product mindset and ability to work autonomously
• Comfortable with Docker, SQL, testing and scalable architecture
• Fluent Spanish and English

Nice to have

• Experience with LLMs, STT/TTS, OpenAI, Whisper, ElevenLabs or Deepgram
• Experience with LangChain, LangGraph or similar AI orchestration tools
• AWS/GCP, CI/CD and observability experience
• Startup or early-stage product company experience
• PRevious experince leading a team or acting as a principal

What you’ll be doing

• Building scalable APIs and services for real-time voice interactions
• Developing product features end-to-end with React, TypeScript and AI infrastructure
• Integrating LLM, STT and TTS workflows into production
• Working on agentic and multi-agent workflows
• Improving architecture, observability, testing and engineering quality
• Working directly with the founders and senior team to shape the platform