> Markdown version of [/jobs/ext/3520692-back-end-engineer](https://www.wearedevelopers.com/jobs/ext/3520692-back-end-engineer). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Back End Engineer - **Company:** Descrial Descrial - **Location:** London, UK - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Java (Programming Language), Amazon Web Services, Amazon S3, User Authentication, Software as a Service, Continuous Integration, Data Validation, Cursor, Linux, Python (Programming Language), PostgreSQL, Open Web Application Security, Software Systems, SQL Databases, Large Language Models, Caching, Git, Fastapi, Event Driven Architecture, Information Technology, Jenkins - **Published:** October 1, 2026 - **Apply:** https://www.apply4u.co.uk/jobs/back-end-engineer/49619825 ## About the Role rates and token cost. You build validation, schema enforcement and safe failure behaviour for outputs that may be well-formed yet wrong. Authentication, authorisation, secrets, input validation, OWASP awareness and audit trails are part of everyday engineering. The delivery and cost You deploy and operate on AWS using EKS/ECS patterns, RDS and S3 through Jenkins quality gates. You improve queries, caching, asynchronous throughput and right-sizing. For model-calling services, you build queueing, rate limits and orchestration that account for cost. Your experience * You have real multi-tenant or enterprise-system experience with isolation, permissions and auditability. * You have 5+ years in backend engineering for production SaaS or platform systems. * You have strong Python, using FastAPI or comparable frameworks, solid SQL/PostgreSQL and the ability to work at * Java/Spring service boundaries. * You have production AWS experience and are comfortable with Git, CI/CD and Linux. * You use AI coding tools daily, such as Cursor or Claude Code, and have a considered view of where they help. * You have a degree in engineering, computer science or a related field, or equivalent experience. Useful to have, none required * Java/Spring depth alongside Python * Event-driven architecture, queues and workflow engines * Financial services or regulated-industry systems * LLM service integration patterns The reality This will be difficult. It demands pace and accuracy. We are building autonomous systems inside high-stakes live businesses, where decisions carry real consequences and impact and waiting for everyone to agree is not always an option. The systems will sometimes get things wrong. In this phase the London team needs to create the evaluations, visibilities and safeguards that catch mistakes early, reducing them over time and stopping the same failures happening again. If you want to build the foundations of an enterprise grade technology platform ## Related Videos - [How a Small Team Shrank a Microsoft Monorepo by 94%](https://www.wearedevelopers.com/videos/1236-how-a-small-team-shrank-a-microsoft-monorepo-by-94) - [Docker network without Docker](https://www.wearedevelopers.com/videos/1418-docker-network-without-docker) - [".Net is too slow" was not an option](https://www.wearedevelopers.com/videos/100176-net-is-too-slow-was-not-an-option) - [Inside Bitpanda's Tech Stack: Scaling a European Fintech Leader - Markus Dorner](https://www.wearedevelopers.com/videos/1979-inside-bitpanda-s-tech-stack-scaling-a-european-fintech-leader-markus-dorner) - [Git for Code Reviews](https://www.wearedevelopers.com/videos/429-git-for-code-reviews) - [Shipping Faster with Less: Render on Cloud Hosting, AI Workloads, and the Future of DevOps](https://www.wearedevelopers.com/videos/1894-shipping-faster-with-less-render-on-cloud-hosting-ai-workloads-and-the-future-of-devops) ## Related Articles - [Software Engineer Salary London](https://www.wearedevelopers.com/magazine/252-software-engineer-salary-london) - [The 7 Most Popular Backend Frameworks for Developers](https://www.wearedevelopers.com/magazine/403-the-7-most-popular-backend-frameworks-for-developers) - [Top-Paying Tech Jobs (with Salaries)](https://www.wearedevelopers.com/magazine/372-top-paying-tech-jobs-with-salaries) - [The Most Popular IT Jobs on the Market](https://www.wearedevelopers.com/magazine/376-the-most-popular-it-jobs-on-the-market) - [Data Engineer Salary UK](https://www.wearedevelopers.com/magazine/253-data-engineer-salary-uk) - [What’s the Difference Between Frontend and Backend Development?](https://www.wearedevelopers.com/magazine/240-what-s-the-difference-between-frontend-and-backend-development)