Full Stack Engineer - AI, LLM

Oliver Bernard; United Kingdom; On-site; GBP 50,000 - 70,000; Full time

Job summary

A software development firm in the United Kingdom seeks a Full Stack Engineer to join its product team. You will design and maintain web application features using Next.js, Node, TypeScript, and React, as well as integrate AI models and manage database architecture. Ideal candidates will have proven experience with complex codebases and modern web development, especially in dynamic environments.

Qualifications

• Proven experience working within complex, unified codebases with AI/LLM components.
• Expertise in modern web development with Next.js, tRPC, TypeScript, and Prisma.
• Strong understanding of database design and optimisation, particularly with MySQL.
• Hands-on experience integrating with AI models like ChatGPT or Gemini.
• Familiarity with LangChain for multi-step AI workflows.
• Ability to quickly learn new technologies and deliver production-ready features.

Responsibilities

• Design, build, and maintain web application features using Next.js, Node, TypeScript, and React.
• Contribute to and optimise the monorepo for B2B SaaS platforms and AI modules.
• Integrate and fine-tune commercially available LLMs through prompt engineering.
• Implement multi-step LLM workflows using orchestration frameworks.
• Design and manage database architecture using MySQL.
• Develop type-safe RPC endpoints with tRPC and TypeScript.
• Rapidly onboard to the modern TypeScript stack.

Skills

Next.js

tRPC

TypeScript

Prisma

MySQL

AI integration

LangChain

Web application development

Job description

Base pay range

This range is provided by Oliver Bernard. Your actual pay will be based on your skills and experience — talk with your recruiter to learn more.

About the Role

As a Full Stack Engineer, you will be an integral part of their product team, working within a unified codebase that powers their B2B software and custom AI modules. Your role will encompass the entire feature lifecycle, from initial design and data structuring to advanced AI integration, ensuring robust, scalable, and high-performance solutions.

Key Responsibilities

• Design, build, and maintain web application features using Next.js, Node, TypeScript and React
• Contribute to and optimise their monorepo, which includes both B2B SaaS platforms and AI/LLM modules.
• Integrate and fine-tune commercially available LLMs (e.g., OpenAI, Gemini) through prompt engineering and inference pipeline management.
• Implement multi-step LLM workflows using orchestration frameworks like LangChain.
• Design, optimise, and manage database architecture using MySQL.
• Develop and maintain type-safe RPC endpoints with tRPC and TypeScript for seamless front-end and back-end communication.
• Rapidly onboard to their modern TypeScript stack, ensuring high-velocity feature delivery.

Required experience

• Proven experience working within complex, unified codebases that combine application logic with AI/LLM components.
• Expertise in modern web development with Next.js, tRPC, TypeScript, and Prisma.
• Strong understanding of database design and optimisation, particularly with MySQL.
• Hands-on experience integrating with AI models like ChatGPT or Gemini, including prompt crafting and API management.
• Familiarity with LangChain or similar orchestration tools for multi-step AI workflows.
• Ability to quickly learn new technologies and deliver production-ready features in a dynamic environment.

Preferred Qualifications

• Experience deploying and fine-tuning custom AI models.
• Background in developing B2B software platforms with multi-user support.

Seniority level

• Mid-Senior level

Employment type

• Full-time

Job function

• Information Technology and Engineering

Industries

• Software Development