Full Stack Engineer - AI Product Delivery, Central Government

A high-profile central Government AI unit is looking for a Full Stack Engineer to build and maintain features on a Next.js frontend and FastAPI backend used by frontline justice staff. You will personally own both sides of the stack, integrating AI (LLM workflows, speech-to-text, document generation) and shipping it into production with a measurable, tangible outcome for the people using it.
This role is held to the same standard as the unit's senior engineers: hands-on ownership of shipping AI products end to end, with security and production reliability considered throughout, not bolted on afterwards. The unit sees itself as a disruptor within government and moves quickly, working directly with the frontline staff it builds for.
What you'll do
Build and maintain full-stack features end to end on a Next.js frontend and a FastAPI backend, on Azure infrastructure (App Services, Blob Storage, Postgres, Terraform-managed containers)
Integrate AI features into production, such as LLM workflows, speech-to-text and document generation, with a real, measurable outcome for users
Co-build with frontline users in courts, prisons or probation, translating what they need into working software quickly
Iterate fast while keeping security and reliability part of the same work throughout
What you'll need to show (this is where most applicants fall down)
Genuine personal ownership of both the frontend and the backend, not one side with light exposure to the other. Expect to be asked directly what you built yourself on each side
Real interface complexity on the frontend, not a single basic screen: separate views for different user types, an admin or ops view alongside the end-user one, or several distinct workflows within the same product
Strong production experience with React/Next.js and a Python backend (FastAPI, Django or Flask)
Postgres schema design and migrations, and solid API and authentication integration, ideally including OAuth and Microsoft Entra ID (Azure AD): app registration, token issuance and validation, and how that protects your API routes
Hands-on experience shipping AI-native features into production with a measurable outcome for users, not just technical exposure to the underlying tools
Version control, CI/CD, and strong communication with non-technical stakeholders
Also useful
LLM feature-building: prompt engineering, structured outputs, multi-provider routing, retrieval-augmented generation
Observability tools such as Langfuse or LangSmith
Terraform and Azure (or equivalent AWS/GCP experience)
Speech-to-text or audio pipelines
Designing AI safeguards: prompt-injection defences, least-privilege access, human approval points, auditable decision trails
A startup or entrepreneurial mentality, and genuinely current knowledge of AI
Rate and logistics
Day rate up to £700, inside IR35, fully or largely remote. You will need to hold, or be eligible for, UK government security clearance (BPSS as a minimum; SC is desirable).
How to apply
This search is being run by Goldfern, specialists in senior interim recruitment into Government Corporate Services. To apply or find out more, contact Lester Fernando at lester@goldfern.co.uk.

Work arrangement
Yes