AI Full-Stack Engineer

AI Full-Stack Engineer (Agents & Automation) – Hybrid Lisbon

About the Role

Unlocking Tech is hiring an
AI Full-Stack Engineer
to help us build and scale our AI-powered agents and automation products.

You'll work at the intersection of
LLMs, backend engineering, and product
, designing and shipping end-to-end solutions: from a voice or WhatsApp agent talking to patients or leads, to the backend services, RAG pipelines, and cloud infrastructure behind it.

Our stack powers automation for
clinics, real estate, industry, and internal platforms
, with use cases like:

• AI receptionists for clinics (voice + WhatsApp),
• lead qualification agents for sales teams,
• document/question answering copilots on top of PDFs, contracts, and emails,
• internal tools for our own omnichannel AI platform.

This is a hands-on engineering role: you'll both
build
and
ship
.

Key Responsibilities

• Design, build, and maintain
  end-to-end AI features
  : from prompt / agent design all the way to API endpoints and (sometimes) basic UI integration.
• Implement and evolve
  LLM-powered agents
  (voice, chat, WhatsApp, web) using LLM APIs, tools, memory, RAG, and external system integrations.
• Build
  RAG/document intelligence pipelines
  on top of PDFs, DOCX, emails, and other unstructured data (parsing, chunking, embeddings, retrieval, evaluation).
• Develop and maintain
  backend services and APIs
  (REST/webhooks) in or Python that integrate with CRMs, telephony providers, and third-party SaaS.
• Work with
  vector databases
  and relational databases to store embeddings, logs, sessions, and agent state.
• Deploy and operate services on
  Azure / other cloud providers
  using Docker and basic CI/CD.
• Implement
  monitoring, logging, and tracing
  for AI services (latency, token usage, errors, user feedback).
• Collaborate with frontend engineers and product to ship features quickly, gather feedback, and iterate.
• Document architecture, APIs, and technical decisions in a way the rest of the team can follow and extend.

Must-Have Qualifications

• 3+ years of experience as a Software Engineer (backend or full-stack)
  shipping production systems.
• Strong skills in at least
  one
  of:
• / TypeScript
• Python
• (.NET is a plus because of our legacy stack)
• Solid experience building
  REST APIs
  , integrating with external APIs, and working with webhooks.
• Hands-on experience using
  LLM APIs
  (OpenAI, Anthropic, etc.) to build real features (chatbots, agents, copilots, document Q&A, etc.).
• Understanding of
  RAG patterns
  (chunking strategies, embeddings, retrieval, context window management).
• Experience with
  databases
  (PostgreSQL/MySQL) and at least one
  vector database or extension
  (Pinecone, pgvector, Qdrant, Weaviate, etc.).
• Comfortable working with
  Docker
  , Git, and basic CI/CD workflows.
• Familiarity with a major cloud provider (
  Azure is a plus
  ).
• Ability to own features end-to-end, communicate clearly in English, and work in a small, fast-moving team.

Nice to Have

• Experience building AI agents with
  LangChain, LlamaIndex, Haystack
  or similar frameworks.
• Integrations with
  telephony / messaging
  providers (Twilio, VAPI, Zadarma, WhatsApp Business API, SMS gateways).
• Experience with
  n8n
  or other automation/orchestration platforms.
• Background in
  document AI
  : OCR, layout-aware models, Azure Document Intelligence, Google Document AI, or similar.
• Some frontend experience (
  React or Angular
  ) to help close the loop on small UI tasks when needed.
• Knowledge of
  LLM evaluation, guardrails, hallucination mitigation
  , and security/privacy concerns around AI.
• Exposure to
  Kubernetes
  , Terraform, or more advanced DevOps is a plus but not required at the start.

Why Join Unlocking Tech?

• Work on
  real, production-grade AI agents and automation
  , not just prototypes or internal POCs.
• Be part of a
  fast-moving team
  building our own
  AI-powered omnichannel platform
  (voice, WhatsApp, web).
• High autonomy and
  direct impact
  : your work will go live quickly and be used by real users and clients.
• Opportunity to
  experiment, learn, and ship
  across different verticals (healthcare, real estate, industry).
• Hybrid work model in Lisbon, close collaboration with the CEO and core engineering team.

How to Apply

Send your CV or portfolio to:

• Or reach out directly to our CEO, Miguel Marques
  , via LinkedIn.