Staff BackEnd Engineer - Series A - HR Tech

fledge; Barcelona; A distancia; EUR 90.000 - 150.000; Jornada completa

Ventajas ofrecidas por este puesto de trabajo

Remote policies

Relocation support

Visa sponsorship

Descripción de la vacante

Fledge is seeking a Staff Backend Engineer to join an elite AI platform team. You will serve as the technical architect, focusing on Python/Django backend development and scalable AI-native architectures to orchestrate autonomous recruitment workflows.

You will collaborate with AI researchers, design robust systems for low latency, and mentor peers while delivering full-stack features. The role offers top-tier compensation, equity, remote-friendly policies, relocation and visa sponsorship.

Formación

• Expert-level proficiency in Python with extensive experience in Django, Django Channels, FastAPI, ASGI, and async programming.
• Strong system design skills and ability to articulate technical trade-offs.
• Proven skills in building scalable backend systems handling 100+ concurrent AI workflows with low latency.
• Deep knowledge of LLMs, including prompt engineering, chaining, caching, fine-tuning, and usage of open-source (Llama, Mistral) or closed-source models (OpenAI, Anthropic).
• Experience with retrieval-augmented generation (RAG), vector databases, and semantic search implementations.
• Familiarity with AI agentic frameworks, multi-agent orchestration, planning, and reasoning systems.
• Hands-on experience integrating speech-to-text, text-to-speech, telephony (Twilio, IVR), and voice activity detection into production systems.
• Proficiency with AI-assisted development tools and ability to deliver full-stack features (backend + frontend) efficiently.
• Good frontend skills with JavaScript/TypeScript and React (AI-assisted vibe coding).
• Understanding of asynchronous message queues (Celery, RabbitMQ/Redis) and data storage technologies (PostgreSQL, Redis).
• English and Spanish fluency

Responsabilidades

• Lead the development of full-stack solutions, from designing intuitive user interfaces to crafting robust backend systems.
• Collaborate with cross-functional teams, including AI researchers and data scientists, to seamlessly integrate AI models into user-centric applications.
• Architect scalable, maintainable systems that support the company’s rapid growth and mission to make a meaningful environmental impact.
• Drive innovation by exploring and implementing modern frameworks, APIs, and cloud solutions.
• Mentor and support junior developers, fostering an environment of collaboration and technical excellence.
• Automate and optimize systems to deliver faster, more efficient solutions to both users and internal teams.

Conocimientos

Python

Django

Async programming

System design

LLMs

RAG

PostgreSQL

Redis

Frontend basics

Celery

CI/CD

Docker

AWS

Educación

Bachelor’s degree in Computer Science

Herramientas

Docker

Kubernetes

PostgreSQL

Redis

Terraform

Descripción del empleo

Fledge

We are a boutique Talent search firm connecting exceptional Talent with the most innovative companies in the AI and software development industries across EMEA. Our clients are among companies with innovative products that have a positive impact on our societies, and we present them with a solution model between fine consulting and flexible recruitment process outsourcing :

• Fractional Talent Acquisition Advisory
• Recruitment operation tools
• On-demand Talent sourcing expertise

Job Summary

We are seeking a Staff Backend Engineer to join an elite team of industry leaders building an AI platform tailored for the HR sector. You will be the technical architect and backbone of the intelligent HR platform. You will focus on the backend development with Python/Django and the design of scalable AI-native architectures to orchestrate complex, autonomous recruitment workflows. You will leverage cutting-edge AI-assisted development tools, such as Cursor and Claude Code, to prototype and ship complete, full-stack features rapidly with minimal handoffs.

This is an opportunity to build production-grade conversational AI systems that integrate LLMs, build our agent framework, use real-time voice and telephony interfaces, and enable zero-touch recruitment automation.

In this role, you will

• Lead the development of full-stack solutions, from designing intuitive user interfaces to crafting robust backend systems.
• Collaborate with cross-functional teams, including AI researchers and data scientists, to seamlessly integrate AI models into user-centric applications.
• Architect scalable, maintainable systems that support the company’s rapid growth and mission to make a meaningful environmental impact.
• Drive innovation by exploring and implementing modern frameworks, APIs, and cloud solutions.
• Mentor and support junior developers, fostering an environment of collaboration and technical excellence.
• Automate and optimize systems to deliver faster, more efficient solutions to both users and internal teams.

Required Skills and Qualifications

• Expert-level proficiency in Python with extensive experience in Django, Django Channels, FastAPI, ASGI, and async programming.
• Strong system design skills and ability to articulate technical trade-offs.
• Proven skills in building scalable backend systems handling 100+ concurrent AI workflows with low latency.
• Deep knowledge of LLMs, including prompt engineering, chaining, caching, fine-tuning, and usage of open-source (Llama, Mistral) or closed-source models (OpenAI, Anthropic).
• Experience with retrieval-augmented generation (RAG), vector databases, and semantic search implementations.
• Familiarity with AI agentic frameworks, multi-agent orchestration, planning, and reasoning systems.
• Hands-on experience integrating speech-to-text, text-to-speech, telephony (Twilio, IVR), and voice activity detection into production systems.
• Proficiency with AI-assisted development tools and ability to deliver full-stack features (backend + frontend) efficiently.
• Good frontend skills with JavaScript/TypeScript and React (AI-assisted vibe coding).
• Understanding of asynchronous message queues (Celery, RabbitMQ/Redis) and data storage technologies (PostgreSQL, Redis).
• English and Spanish fluency

Preferred Skills and Qualifications

• Great communicator:You can help clients understand the value we bring and help our team better understand our clients
• Resilience: You can ride the ups and downs of the job and stay balanced through it all
• Results-based:You own the outcome
• Team player:You put the team before yourself
• Organized:You can keep track of your workload and ensure critical things are not missed
• Experience with DevOps practices: CI/CD pipelines, containerization (Docker), cloud platforms (AWS, Azure).
• Knowledge of production monitoring, logging, alerting, and security best practices for enterprise B2B AI solutions.
• Familiarity with multi-modal conversational interfaces and fallback mechanisms for robust production deployment.
• Passion for working in fast-paced startup environments with a hands-on, ownership-driven mindset.

In return, they offer

• Top of the market salary
• Equity plan
• Remote policies
• Relocation support and Visa Sponsorship

Diversity, Equity, Inclusion, and Belonging

We are committed to enabling everyone to feel included and valued, and we trust our partners to do the same. Both the company and its culture are strongest when composed of diverse experiences and backgrounds.

All qualified applicants will receive consideration for employment without regard to age, color, family, gender identity, marital status, national origin, physical or mental disability, sex (including pregnancy), sexual orientation, or any other characteristic protected by applicable laws.

Important

If you have a medical condition or an individual need for an adjustment to our process, and you believe this may affect your ability to be at your best, please let us know so we can discuss how we can best support you and make any necessary adjustments.

In case of any doubts or questions, please contact here: [e-mail]