NatSec Tech Lead: AI, Data & Secure Architecture

About Zaizi

Zaizi is a digital consultancy specialising in delivering user-centred, secure, and scalable services for complex public sector challenges. We work in highly regulated environments, partnering closely with our clients to design and build modern digital platforms.

We are seeking a high-caliber, entrepreneurial Engineering Lead to build and steer high-performing, multi-disciplinary Agile teams. You will be responsible for architecting and delivering innovative solutions to "hard" technical problems within the UK National Security (Nat Sec) domain. This role requires a blend of hands-on technical excellence, strategic leadership of small engineering squads, and the ability to navigate the unique security and data challenges of the UK defense and intelligence landscape.

• Team Leadership & Delivery:
  Lead and mentor small, high-velocity engineering teams (4–8 people). You will be responsible for fostering a culture of technical excellence, psychological safety, and rapid delivery using Agile/Dev Sec Ops  methodologies.
• Architectural Guidance:
  Serve as the Technical Authority for client projects, bridging the gap between high-level strategy and low-level implementation. You will design resilient, scalable architectures that account for the constraints of high-side/disconnected environments.
• AI & Data Engineering:
  Lead the implementation of the "underpinning tech" for AI, including data pipelines (ETL/ELT), vector databases for RAG (Retrieval-Augmented Generation), and the deployment of LLMs/ML models within secure infrastructure.
• Nat Sec Stakeholder Management:
  Act as a trusted advisor to UK Government (HMG) stakeholders. You must understand the nuances of Policy and Assurance (e.g., JSP 440, IS1&2) and how to deliver "Secure by Design" software.

Strategy & Road mapping:
Work alongside client engineering communities to develop technical roadmaps that prioritize interoperability, data sovereignty, and the migration from legacy systems to modern cloud-native architectures (AWS/Azure).

• Essential:
  Software Engineering & Leadership
• Languages:
  
  Expert-level proficiency in Python, GoLang, or Java; with strong Type Script/Node.js for full-stack/service-layer delivery.
• Cloud & Infrastructure:
  Hands-on AWS or Azure architecture; mastery of Terraform (IaC), Kubernetes (EKS/AKS), and Container Orchestration.
• Data Foundations:
  Deep knowledge of SQL (PostgreSQL) and No
  
  SQL (MongoDB/DynamoDB) with an emphasis on data modeling for high-availability systems.
• Engineering Rigour:
  Proven experience in CI/CD pipeline construction, TDD/BDD, and Micro-services architecture within a Git Lab/Git Hub environment.
• Security & National Security (Nat Sec):
  Solid understanding of "Secure by Design" principles, OAuth2/OIDC, and building for UK Sovereign Cloud or disconnected environments. Practical application of BDD/TDD and a "Security First" approach to the software development lifecycle (SDLC).
• Desirable: AI & Data Underpinnings
• Vector Databases:
  Experience with high-dimensional data retrieval using Milvus, Weaviate, or Pinecone (essential for RAG architectures).
• Data Orchestration:
  Familiarity with Airflow, Prefect, or Dagster for managing complex data movement and model training pipelines.
• Search & Discovery:
  Advanced Elastic Search/Open Search for semantic search and large-scale indexing.
• AI Frameworks:
  Exposure to Lang Chain, Llama Index, or Hugging Face libraries for integrating Large Language Models (LLMs) into production applications.
• Model Ops (MLOps):
  Understanding the lifecycle of a model—from deployment and monitoring to versioning—using tools like MLflow or Kubeflow.

• Desired Experience & Context
• UK Nat Sec Landscape:
  Proven experience working within the UK National Security community…