Tendios is a SaaS platform for Spanish public procurement intelligence. Our products, Bid and Create, help companies find, analyse and win public tenders. Tender documentation is long, unstructured and full of legal and technical detail, which makes it an idóneo ground for applied AI. We are looking for a Senior AI/ML Engineer who designs the intelligence behind our products and ships it into production code. You will decide which model solves each problem, whether a commercial API, a fine-tuned open-source model or a combination, and make it fast, reliable and affordable at scale. You will prototype in Python, then integrate and ship features in our Node.js / NestJS / TypeScript platform alongside the rest of the engineering team. You will join our AI & Data squad. Choose the right approach per use case: prompting, RAG, fine-tuning, distillation or classic ML, and justify it on quality, latency and cost. Build retrieval pipelines: chunking, embeddings, hybrid search and reranking over large document collections. Commercial LLMs, cost-efficient Own our usage of commercial providers (Anthropic, OpenAI, Google and others) and keep cost per feature under control. Apply prompt caching, batch APIs, model routing and cascading, semantic caching, context compression and token budgets. Track cost, latency and quality per feature and per customer, and set alerts before bills surprise us. Evaluate, fine-tune (LoRA / QLoRA) and deploy open-weight models such as Llama, Mistral, Qwen or Gemma where they beat APIs on cost, privacy or control.



Build the data pipelines and labelled datasets needed for training and evaluation. Ship AI features end to end in our Node.js / NestJS / TypeScript platform: Build evaluation suites and regression tests so model or prompt changes never silently degrade quality. 5+ years of software engineering, including 2+ years building LLM or ML features that run in production. ~ Strong Python for ML work: PyTorch, Hugging Face Transformers and the surrounding data tooling. ~ Solid TypeScript and Node.js in production; NestJS experience or the ability to become productive in it quickly. ~ Deep hands-on knowledge of commercial LLM APIs, including concrete examples of how you reduced their cost without losing quality. ~ RAG in production: embeddings, vector search (e.g. pgvector, Qdrant, OpenSearch), hybrid retrieval and reranking. ~ An evaluation mindset: you build test sets, use LLM-as-judge carefully and measure before you claim improvements. ~ Docker, CI/CD, cloud infrastructure, observability and on-call ownership of what you ship. ~ Fluent English for technical work. Spanish, since our source documents and many users work in Spanish. GPU infrastructure and cost management on AWS, GCP or specialised GPU providers. Knowledge of public procurement, legal or other document-heavy domains. Remote from anywhere in Spain, or hybrid from Barcelona. A 16-person engineering organisation in four squads; you join the AI & Data squad and work closely with product squads.

📌 DESARROLLADOR FULLSTACK (Barcelona)
🏢 Tendios
📍 Barcelona