51 to 75 of 82 Legacy Code Jobs in London

for the bank. We are seeking a highly experienced Senior Java Lead Developer to modernize our core financial accounting systems. You will play a critical role in rewriting our legacy sub-ledger application to a modern Java-based architecture. This involves analyzing existing code, designing equivalent Java components, and ensuring a seamless transition while maintaining system functionality and … design, coding, testing, debugging, and implementation Analyze existing modules and shell scripts to design equivalent Java components Develop and implement high-performance, scalable, and secure Java applications to replace legacy code Write clean, well-documented, and testable Java code Collaborate with architects and other developers to define the migration strategy and ensure a smooth transition Work with … relational databases, primarily Sybase ASE and MS SQL, to adapt existing database schemas and queries to the new Java architecture Thoroughly test and validate the migrated Java code to ensure functional equivalence with the legacy system Troubleshoot and resolve technical issues during the migration process Participate in code reviews and contribute to improving development processes Allocate work More ❯

for the bank. We are seeking a highly experienced Senior Java Lead Developer to modernize our core financial accounting systems. You will play a critical role in rewriting our legacy sub-ledger application to a modern Java-based architecture. This involves analyzing existing code, designing equivalent Java components, and ensuring a seamless transition while maintaining system functionality and … design, coding, testing, debugging, and implementation Analyze existing modules and shell scripts to design equivalent Java components Develop and implement high-performance, scalable, and secure Java applications to replace legacy code Write clean, well-documented, and testable Java code Collaborate with architects and other developers to define the migration strategy and ensure a smooth transition Work with … relational databases, primarily Sybase ASE and MS SQL, to adapt existing database schemas and queries to the new Java architecture Thoroughly test and validate the migrated Java code to ensure functional equivalence with the legacy system Troubleshoot and resolve technical issues during the migration process Participate in code reviews and contribute to improving development processes Allocate work More ❯

will be key to your role, as you help elevate their skills and drive long-term success. Our focus is AWS Serverless & TypeScript, but you'll also consult on legacy code optimisation and replatforming when needed. What we're looking for: Core Skills: - 5 years+ in cloud engineering - Proficient in TypeScript & Node (Python is a plus) - Experience with More ❯

the team, you will collaborate with engineers, product managers, and designers to clarify specifications and build high-quality, well-tested software that provides an excellent user experience. Responsibilities include code reviews, troubleshooting, and bug fixes. This role requires balancing teamwork with independent initiative. You should thrive in cross-functional teams and be capable of owning projects from start to … for 4 hours of overlap with US Central Time. Ability to attend daily standups at 11:00 am US Central Time. Willingness to learn and work with a large legacy codebase. Nice to Have Linux or macOS command-line skills, including zshell or bash. Experience building consumer software products. Focus on user experience. Personal Attributes Passion for independent music More ❯

proprietary trading systems. Accelerate trading and research analysis workflows by utilizing and expanding on DRW’s in-house infrastructure and improve productivity Evaluate new technologies and identify/deprecate legacy code to improve on the current technological stack Collaborate with other engineers, traders, and researchers to design custom frameworks or end-user solutions Write performance sensitive code and user-friendly APIs to facilitate access to our in-house data analysis infrastructure Lead design discussions and conduct code reviews to maintain high standards and quality of written code Requirements: Bachelor’s or Master’s degree in Computer Science or related Engineering discipline 5+ years of experience building demanding, live systems in Python In-depth knowledge More ❯

Why This Role? ? Team Leadership: Manage and mentor a growing team of backend/frontend engineers ? Modern Engineering Environment: Work on a cloud-native, AI-enabled platform with minimal legacy code ? Impactful Work: Influence product direction and contribute to scaling mission-critical systems ? Global Reach: Help deliver a platform used by large enterprise clients worldwide ? Career Growth: Step … needs into technical solutions Help define and execute development processes, sprint planning, and QA workflows Maintain a healthy balance between speed, quality, and technical debt Ensure best practices in code quality, documentation, and DevOps integration Your Profile 4+ years of experience in software engineering, with 1–2+ years in an engineering leadership or management role Strong technical background (you … don’t need to code daily, but should be comfortable leading technical discussions) Proven experience in a SaaS or product-driven environment (B2B a plus) Solid understanding of cloud infrastructure (AWS, GCP), CI/CD workflows, and agile development Interest or experience in AI/ML technologies is a plus Excellent communication skills and a team-first mentality What More ❯

software systems supporting 24/7 global trading. Design and implement full-stack systems Predominately work across Java. Conduct comprehensive testing at unit, functional, and integration levels. Tackle both legacy code enhancements and greenfield development. Qualifications: Proven experience designing, developing, and maintaining mission-critical, high-performance applications. 5+ years of professional experience with Java Knowledge of network communication More ❯

platform and integrations. You'll design internal and external endpoints that will be the foundation to our future growth as we move more into Postgres and away from low-code tools like Airtable. Reliable Systems - Ensure our systems are reliable and resilient so that the team can rely on things "just working" without worrying as we continue to ship … that accurately reflect the world without being overly complex. Architecture mindset: You've made architectural decisions for growing applications. Preferably with experience handling migrations between platforms and moving from legacy code bases to more modern systems. Problem-solving chops: Ability to navigate ambiguous, complex problems. Our domain (leasehold property law) can be intricate - you're eager to dive … into unfamiliar territory and simplify complexity with technology. Comfortable with some frontend: 90% of the development work will be focused on backend code, databases and infrastructure, but 10% of it will be the occasional frontend work with basic HTML/CSS/JQuery (no modern JS frameworks). Leadership and collaboration: You don't need to have been a More ❯

maintaining documentation and records for future reference. Technical Design Author designs and blueprints for the engineering teams to implement and follow. Analyse, understand, and build documentation for the existing legacy system, including its functionalities, challenges, and limitations – sharing your documentation and plans with senior team members to plan for the future Own the Technical Design Authority process, to ensure … Proficient in at least one backend programming language (.NET preferred). Ability to work independently and manage multiple priorities effectively. Strong problem-solving and analytical skills. Experience working with legacy code modernization projects. Knowledge of CI/CD pipelines and DevOps practices. Experience with IaC tools like Terraform or Azure Resource Manager. Experience in containerization technologies like Docker More ❯

ll be a part of team Teza!). Our environment helps people to master their art and have fun doing it. What makes you a match : You love to code and find solutions to complex problems You know how to get people to listen to your ideas You are capable of understanding and improving the legacy codebase Difficult More ❯

by colleagues who are at the top of their fields, pushing the boundaries of technology and finance every day. Innovation & Impact: Work in a modern, young codebase with minimal legacy code and technical debt. You’ll have the freedom to choose the best technology for the job, allowing you to innovate and deliver at an unmatched scale. They More ❯

by colleagues who are at the top of their fields, pushing the boundaries of technology and finance every day. Innovation & Impact: Work in a modern, young codebase with minimal legacy code and technical debt. You’ll have the freedom to choose the best technology for the job, allowing you to innovate and deliver at an unmatched scale. They More ❯

by colleagues who are at the top of their fields, pushing the boundaries of technology and finance every day. Innovation & Impact: Work in a modern, young codebase with minimal legacy code and technical debt. You’ll have the freedom to choose the best technology for the job, allowing you to innovate and deliver at an unmatched scale. They More ❯

by colleagues who are at the top of their fields, pushing the boundaries of technology and finance every day. Innovation & Impact: Work in a modern, young codebase with minimal legacy code and technical debt. You’ll have the freedom to choose the best technology for the job, allowing you to innovate and deliver at an unmatched scale. They More ❯

innovative risk management tools using technologies like MS SQL Server, C#, Python, and MS Azure. Key Responsibilities Extend and upgrade Credit Risk Pricing Calculators and Control-M batches Upgrade legacy codebases to .NET Core Performance tuning and rigorous testing of codebase Requirements Strong skills in C#, .NET Framework & SQL Server Experience building .NET Core Web APIs Hands-on experience More ❯

Responsibilities Researching, designing, implementing, and managing software programs Testing and evaluating new programs Identifying areas for modification in existing programs and subsequently developing these modifications Writing and implementing efficient code Determining operational practicality Developing quality assurance procedures (automated tests) Deploying software tools, processes, and metrics Maintaining and upgrading existing systems Working closely with other teams Skills Degree in Informatics … Playwright Experience in production monitoring, alerting, and building resilient front-end systems Deep understanding of web performance optimization and best practices Familiarity with Redux is a plus, as some legacy code still relies on it Willingness to participate in a rotational on-call schedule for 24/7 production support (approximately 1 week every 2 months, with a More ❯

Engineer who can design, build, and maintain scalable software solutions underpinning Certn’s core platform. As a senior member of the engineering team, you’ll drive technical decisions, ensure code quality, and mentor junior developers. You’ll collaborate with Product Managers and cross-functional partners to deliver high-impact features and drive continuous improvements in performance, reliability, and development … practices. What you will be doing: Software Development: Collaborate with cross-functional teams to deliver customer-facing solutions. Own code quality, test coverage, observability, and documentation—from high-level architecture down to sequence diagrams. Take charge of high-priority bug fixes and unblock customers with rapid triage and resolution. Codebase Maintenance: Refactor legacy code, squash technical debt More ❯

for new and existing code. Write clear documentation for tools and workflows created. Participate in discussions and brainstorming sessions with developers and stakeholders. Provide thorough, thoughtful, and useful feedback (code reviews, mentoring those with less experience, buddy checks, etc.). Engage in team-based problem solving to diagnose unexpected issues within the realms of virtual production and animation, including … least one DCC (Maya, MotionBuilder, etc). Tools for virtual production stages, layout teams and/or animation teams. Experience writing database and event driven toolchains. Experience supporting large, legacy codebases. PLUSES Please note that these are desirable skills and are not required to apply for the position. 3+ years of experience with writing Qt based tools and plugins More ❯

end-to-end autonomous driving: ranging from initial data strategy, design, development, experimentation, evaluation and deployment. Resolve ambiguities and address uncertainties arising from complex projects involving multiple teams and legacy codebases. Enable and help other colleagues on the team to be more effective through leading by example when it comes to writing high-quality code, being rigorous with More ❯

live PnL attribution and feedback to researchers & traders. Hire and mentor the team that will scale this from “clever prototype” to “firm‐wide PnL driver”. Green‐field. No legacy code. You set the standards. The Opportunity All the levers, none of the red tape – direct line to the head of the HFT business, a chance to own the More ❯

live PnL attribution and feedback to researchers & traders. Hire and mentor the team that will scale this from “clever prototype” to “firm‐wide PnL driver”. Green‐field. No legacy code. You set the standards. The Opportunity All the levers, none of the red tape – direct line to the head of the HFT business, a chance to own the More ❯

live PnL attribution and feedback to researchers & traders. Hire and mentor the team that will scale this from “clever prototype” to “firm-wide PnL driver”. Green-field. No legacy code. You set the standards. The Opportunity All the levers, none of the red tape – direct line to the head of the HFT business, a chance to own the More ❯

development of ML models for end-to-end autonomous driving, including data strategy, design, experimentation, evaluation, and deployment. Resolve ambiguities and uncertainties in complex projects involving multiple teams and legacy codebases. Lead by example to promote high-quality coding, rigorous ML experimentation, and knowledge sharing among team members. Collaborate with stakeholders across different teams and time zones to define More ❯

is a huge bonus! You will be helping to reduce a high-volume of tickets raised by the operations teams of the business, mainly dealing with bug fixes and legacy code/application upgrades within their desktop and web applications and liaising directly with the end users. Further into the contract once the support ticket volume is sufficiently … reduced you'll start to look for opportunities to improve legacy code and applications. This is for an urgent start, so if you have the required availability, tech skills, experience with application engineering and your own Ltd company, we'd love you to apply and set up a call. More ❯

products. Your contributions will have a direct impact on the profitability of our strategies providing a competitive edge in the markets. Key responsibilities/Day-to-day: Optimize quantitative code and numerical methods Collect data about trading and research needs for multi-asset trading focusing on futures Adapt, fix, write tests, or in some cases re-implement strategies execution … code Build analytics for understanding how to optimize execution for existing strategies Basic Requirements: Practical knowledge of Data Analytics with Python Proficiency with C Java Computer Science/Math or similar degree At least 2 years of market experience, preferably in Futures Trading Nice to have Requirements: Previous experience working with FIX Previous experience with quant trading What you … ll be a part of team Teza!). Our environment helps people to master their art and have fun doing it. What makes you a match: You love to code and find solutions to complex problems You know how to get people to listen to your ideas You are capable of understanding and improving the legacy codebase You More ❯