Backend Jobs in United Kingdom

Backend Engineer: Python, REST APIs & Cloud

Agile API AWS Azure CI/CD +7 skills

Vallum Associates is hiring a backend engineer to design and build scalable applications with Python (plus some React), craft robust RESTful APIs using FastAPI, and deploy across multi-cloud environments (AWS, Azure, GCP). Day to day involves Agile collaboration, Git workflows, CI/CD, and writing clean, tested code.

Client Server Limited

C++ Backend Engineer - Low-Latency Trading Systems

HireHi is seeking a senior C++ backend engineer to redevelop a core equity trading system for the EMEA market. You will design, build, and optimise large data‑intensive backends running on Linux, collaborating directly…

Backend Engineer - Python/Django for Climate Tech

Electroverse is hiring a backend engineer in London to build scalable Python/Django software supporting the global EV transition, with a focus on observability, data analysis, defensive programming, and CPO integrations.

Observability

Government Digital Service

Backend Developer - Public Services & AI (UK)

UKMiddle

A mid-level backend developer building and maintaining scalable, secure services behind UK government digital products such as GOV.UK Pay, GOV.UK Notify, GOV.UK App and GOV.UK Mailbox. Day to day you write backend code in cross-functional teams serving millions of UK users, with opportunities to present at conferences and use learning budgets.

NextGenEnergyJobs

Backend Developer

API CI/CD Django Git GraphQL +2 skills

Backend Software Engineer at Electroverse (London) helping build the platform underpinning the global EV transition. Day to day: writing robust Python/Django services and REST/GraphQL APIs, integrating CPO and third-party APIs (OCPI), and improving observability, CI/CD and data architecture to scale globally.

Wolviston Management Services

Software Developer - C# / ASP.NET Core Backend

Azure Azure DevOps C# DevOps .NET +3 skills

A software developer in Thornaby on Tees develops, optimises and maintains high-performance web applications and internal systems for the company's digital platforms. The stack centers on C# and ASP.NET Core MVC, with Azure DevOps, Azure SQL, and Git.

Galaxy

VP, Senior Backend Developer - Blockchain Infrastructure

Open 120d UKC-level

AI API Api Design Automation AWS +19 skills

Designs and builds backend systems for blockchain infrastructure and staking products, focusing on Ethereum-based systems, APIs, and distributed systems using Golang and cloud-native tools.

your Jared

Senior Backend Engineer - Remote | Node.js, TypeScript, AWS

UKContractSenior

API AWS Fintech Node.js Serverless +1 skills

Senior Backend Engineer on a 12-month remote, outside-IR35 contract building and owning scalable backend services at fintech company your Jared. Day to day you design resilient APIs and architecture using Node.js, TypeScript and AWS serverless technologies while working with product and ops teams.

Push Security Ltd

Remote Senior Backend Engineer - Python + AWS Serverless

RemoteUKSenior

AWS Cybersecurity Python Serverless

Push Security is hiring a remote-first (UK-based) Senior Backend Engineer to design, build, and run large-scale, high-performance systems behind its cybersecurity product, owning features end to end with a focus on Python, AWS serverless, and scalable infrastructure.

Delaney & Bourton

Remote Ruby on Rails Backend Engineer – eCommerce & Search

Agile AWS E-commerce Elasticsearch Git +5 skills

A senior backend engineer designs, builds, and maintains Ruby on Rails services powering eCommerce and search at Delaney & Bourton. Day to day involves ElasticSearch/AWS OpenSearch, Git, contributing to architecture decisions, and working in Agile Scrum/Kanban teams.

ApplyMint

Senior Backend Engineer, AI Engineering: Chat

Agentic AI AI API Automation Cloud +17 skills

Senior Backend Engineer on GitLab's Duo Chat (Chat Engine) team, building the agentic AI backend for GitLab Duo Chat: Python/LangGraph flow components in the Duo Workflow Service, LLM and multi-agent orchestration, and GraphQL/REST integration with the GitLab Rails monolith. Remote role based in the United Kingdom.

HireHi

Senior Python Backend Engineer | AI Cybersecurity

Django FastAPI Flask React

A senior Python backend engineer will own an AI-cybersecurity product end to end, from customer problem to production: designing complex backend architecture with FastAPI/Django/Flask, deploying React interfaces, and building internal tools at an autonomous startup with direct access to founders.

kraken.com

Senior Backend Engineer — AI Agent Platform (0→1)

Senior backend engineer on Kraken's UK-based Agent Systems team building AI-powered agents that automate internal workflows. Day to day: design inference pipelines over user interactions, prototype and productionize agent behaviors, and architect backend services integrating internal APIs and data sources with safety, observability, and reliability.

AI API Observability

MCS Group | Your Specialist Recruitment Consultancy

Senior Backend Engineer | Ownership, Architecture & AI

API Node.js Python TypeScript

MCS Group is recruiting a Senior Backend Engineer in Belfast for a client's compact Platform team to own backend services, APIs and architecture (~90% backend with some frontend). Core technologies include Node.js/TypeScript, Go and Python, plus databases, security and production reliability.

Maxwell Bond

Senior Backend Engineer - AI-Driven SaaS (London, Onsite)

AI AWS CI/CD FastAPI Java +5 skills

Descrial (hiring via Maxwell Bond) is looking for a Senior Backend Engineer in London to build the multi-tenant data and integration services that connect its Java/Spring core with Python AI services. Day to day is backend SaaS work with Python/FastAPI, PostgreSQL, and AWS, collaborating across London and Bengaluru.

Tech4Good Recruitment

Remote Backend Engineer: Scalable Cloud Platform & AI

RemoteUK

Fully remote backend engineer role: design, build, and scale backend services on Google Cloud Platform to support digital health services, working across cloud infrastructure and AI-assisted workflows to deliver reliable, observable systems.

Senior Python Backend Engineer for Scalable APIs

API Api Design AWS Data Modeling GraphQL +5 skills

Senior Python backend engineer at Octopus Electric Vehicles (part of Octopus Energy Group) building the systems behind an electric car leasing platform. Day to day: owning API design, backend architecture, and data modeling, working with Python, GraphQL, PostgreSQL, NoSQL, and AWS alongside a React/Next.js frontend.

Maxwell Bond

Senior Backend Engineer — Multi-Tenant SaaS (Python/FastAPI)

AWS ECS EKS FastAPI Java +10 skills

A senior backend engineer on Descrial's UK core team designs REST and async services in Python 3.11+/FastAPI with PostgreSQL and async SQLAlchemy, implements multi-tenant isolation and RBAC, and works at Java/Spring boundaries. Deployment is on AWS (EKS/ECS, RDS, S3) with pytest testing and OpenTelemetry observability.

Stackd

Senior Backend Engineer — Data Retention (Ruby, PostgreSQL)

RemoteUKSenior

Agile GitLab PostgreSQL Rails Ruby +1 skills

Senior Backend Engineer at GitLab building data retention, lifecycle-management, schema-change enforcement and data-health tooling that scales across GitLab.com (SaaS) and self-managed instances, using Ruby on Rails and PostgreSQL in a fully remote, agile team.

Maxwell Bond

Senior Backend Engineer – Multi-Tenant APIs & AI Bridges

AI CI/CD Java Python Spring

Senior Backend Engineer at Descrial in King's Cross, London, building the multi-tenant data and workflow services the company runs on, bridging Java/Spring with Python AI services. Day to day: designing REST and async Python services, enforcing tenant isolation and access control, and ensuring safe failure handling and audit trails in a small core team with CI/CD discipline.