17 of 17 Legacy Code Jobs in London

operations – a mature, revenue-generating system that has evolved over years and continues to scale. If you enjoy owning real systems, thinking architecturally, improving legacy code thoughtfully rather than rewriting it, and being trusted to deliver without heavy supervision, this role will feel unusually well-matched. The role … calm, root‐cause mindset Incrementally improving system architecture using sound design principles (including modular design, DDD‐style thinking, and pragmatic architectural patterns) Reviewing code, raising standards constructively, and contributing to a disciplined engineering culture Leveraging modern tooling (including AI‐assisted development) to improve quality and velocity This ...

Keynotes. Kotlin & Jetpack Compose first approach. Over 10M+ downloads. The codebase uses modern Android Jetpack components, Kotlin Coroutines, Flow/StateFlow, and RxJava in legacy areas. Make an impact on millions of customers. Never ending chance of experimenting with latest tech, including KMM, Jetpack Compose and more! We have … extremely comfortable with Kotlin. You know reactive programming techniques. You can contribute to discussions on technical architecture and design. You believe that all code is legacy code if it isn't unit/UI tested. You love agile/scrum and can work as part ...

untangling complex systems and modernising core infrastructure without breaking production. This is an exciting opportunity to modernise core C#/SQL systems! Extract legacy business logic, build clean services, and verify changes in shadow mode with zero downtime to revenue flows. Extract business rules scattered across C#, embedded JavaScript … rules assemblies. Build new services cleanly. with proper Dependency Injection (DI), robust authentication/authorization, structured logging, and full observability. Work fluently across both legacy .NET Framework 4.8 (ASP.NET MVC5, WebAPI 2, EF6) and modern .NET, as both will coexist for the whole transition period. Navigate across the multiple ...

blend of in-office (3 days) and homeworking (2 days) per week. Use your data engineering skills to help Hachette UK migrate from legacy systems to modern cloud technology. Hachette UK is a creative powerhouse and the UK's second largest book publishing group. Our mission is to make … tier data pipelines (Bronze/Silver/Gold architectures) in Microsoft Fabric using PySpark, Data Factory, Lakehouses, and Data Warehouses. Execute the migration of legacy stored procedures, SSIS packages, and database tables into cloud-native, Medallion-architecture solutions. Monitor cloud workloads for performance, reliability, and data quality across modern ...

technologies to improve the capabilities of Risk Management. Key responsibilities: Extending Credit Risk pricing calculators to support additional products and scenarios. Upgrading the legacy codebase to .NET Core. Undertaking performance tuning of existing applications and services. Performing rigorous testing of the codebase, including unit and integration testing. Supporting ...

codebase gets easier for both humans and AI tooling to work in. Improve how the codebase is documented and structured so AI code assistants can be guided effectively, for example context files, architecture notes and structured inline documentation. Convert product specifications into precise engineering specifications, building in enough specificity … context that a code assistant can deliver efficiently and reliably, with minimal iteration, rather than being nudged repeatedly toward a solution. Use proofs of concept to prove out the right level of specification and methodology, so AI-assisted changes land reliably and with confidence. Deliver across a full SDLC ...

development team to maintain and update the bespoke ecommerce platform, taking a proactive approach in evolving the back-end technology stack and migrating legacy code across to an ASP.NET framework. Advocate integration of technologies and development methodologies to help drive the business forward and ensure a robust, scalable … Manager to maintain and update the bespoke Classic ASP ecommerce platform. Develop new features for a localized ASP.NET MVC 5 platform and contribute migrating legacy features over to this new platform. Write maintainable, scalable, fault-tolerant code, utilizing SOLID principles and OO design/architectural patterns, TDD, etc. ...

slowing the pace of new development. Demonstrable hands-on experience applying AI to software engineering at team scale with measurable results (e.g. AI-driven code modernisation, test generation for legacy code or agentic development workflows) and an informed point of view on how AI will change both ...

systems with a constant focus on testing, reliability, scalability, and maintainability. Designing, modeling, and programming in a variety of languages and technologies. Working on legacy code as well as green field development. Initiative driving projects to completion. Learning and promoting new technologies with a focus on best practices. ...

Extensive experience in C++ using modern C++ (C++17/20) while possessing a solid understanding of older standards (C++98/03) for adapting to legacy code and systems seamlessly. Experience in Python. Programming experience in a Linux environment (Windows experience is a bonus). Expertise with Docker ...

lean heavily into AI‐driven development. Using Goldman Sachs' AI tooling and agentic coding assistants, you will govern multiple AI agents, rapidly comprehend large legacy codebases, generate and assess production‐quality code, and accelerate every phase of the software development lifecycle. Your Impact Drive a strategic transformation : Work … centric, AI‐driven world, and define and deliver the requirements for CTL integration. Multiply your output with AI : Orchestrate AI coding agents (e.g., Claude Code, GitHub Copilot, Devin, Gemini Code Assist) across all stages of the SDLC while maintaining mastery, quality, and production fitness over all AI‐generated ...

integrate complex enterprise applications within a global financial services environment. The role will use Java, Oracle and the Spring Framework to support highly customised legacy platforms and process large-scale external data feeds. You will help protect data integrity across downstream ledger, risk and margin systems by documenting data … ingest, transform, and validate large-scale daily CCP clearing and market data feeds. Produce comprehensive architectural specifications and interface inventories by reverse-engineering legacy code, PL/SQL packages, and database dependencies. Establish robust data mappings, lineage tracking, and schema definitions that maintain strict ledger, risk, and margin ...

Hands on experience with Kotlin for server side, or/and React and Typescript for the frontend. Proven track record of refactoring and modernising legacy codebases and architectures, improving performance and maintainability while minimising risk and customer impact. Track record of integrating and optimizing AI/ML-enabled features ...

high-quality engineering on mature platforms. The ideal candidate will have 8-15 years of experience, strong Python skills, and comfort navigating complex legacy code. This position offers an opportunity to make architectural decisions and contribute to the company's operational growth, while working alongside senior decision-makers. #J ...

team in London. You will build high-quality front-end features with React and TypeScript, focusing on clarity, performance, and maintainability. You will refactor legacy code, fix issues across the stack, collaborate with product managers and designers, and provide code reviews while mentoring teammates to improve quality ...

more modern Android development tools, including Jetpack Compose, Coroutines/Flow, MVVM, Webviews, other Jetpack libraries, and modular app architectures Ability to test code and promote a culture of testing Experience with JVM unit testing, instrumented testing, and UI regression testing Comfortable working with cutting-edge technologies and legacy code Experience in, or willingness to take on, a leadership role in team projects Rough understanding of iOS development and interest in learning more Nice to have: familiarity with Swift and ObjectiveC for iOS, Scala and Typescript for server-side development Условия: £82,000 Per year One office ...

serving millions with events, news and app experiences. We seek an experienced iOS engineer to design major features, align iOS/Android APIs, modernise legacy code, and raise release quality through tests and monitoring. You will mentor teammates, collaborate with web/platform teams, and help steer ...