Staff BackEnd Engineer - Series A - HR Tech
FledgeBarcelona, Catalonia, Spain
Posted January 21, 2026
80000 - 120000 USD year
Full Time
About the Company
Fledge is a conscious accelerator that nurtures missionādriven forāprofit startups tackling global challenges such as poverty, hunger, unemployment, community resilience, and environmental sustainability. By combining tailored training, strategic mentorship, and impactāfocused investment, Fledge equips founders with the resources to scale solutions that deliver measurable social and ecological outcomes. Its unique blend of purposeācentric funding and handsāon support differentiates it in the accelerator landscape, positioning Fledge as a catalyst for sustainable entrepreneurship.
Job Description
Fledge is a boutique Talent search firm connecting exceptional Talent with innovative companies in the AI and software development industries. We are seeking a Staff Backend Engineer to join an elite team building an AI platform for the HR sector.
Requirements
- 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
Benefits
- Top of the market salary
- Equity plan
- Remote policies
- Relocation support and Visa Sponsorship