25 of 25 Contract Legacy Systems Jobs in London

Lead AI DevOps Engineer

Hiring Organisation
Lorien
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
Salary negotiable
DevOps Engineer to join a growing engineering capability and play a central role in shaping how AI is embedded into real, production-grade software systems . This is not a traditional people-management role . Instead, you'll lead through technical depth, architectural judgement, and delivery experience by setting … capabilities are integrated into modern software platforms. If you enjoy working where architecture, APIs, DevOps, and AI meet , and you care about building systems that are secure, operable, and genuinely useful, this role offers the chance to have real impact. What you'll be doing Your focus will ...

Dynamics 365 Solutions Architect

Hiring Organisation
Xcede
Location
London, United Kingdom
Employment Type
Contract, Work From Home
Build workflows and automation using Power Automate. Implement plugins, custom APIs, and Dataverse extensions for advanced functionality. Integration & Extensibility Integrate D365 with external HR systems and microservices via REST APIs, and custom connectors. Manage data migration from legacy systems ensuring integrity and consistency. Optimize performance ...

Lead Data Engineer

Hiring Organisation
Lorien
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
Salary negotiable
Lead Data Engineer Hands-on technical leadership building data systems that actually work We're looking for a Lead Data Engineer to join an enterprise data engineering capability and play a critical role in designing, building, and improving real-world data systems . This is not a line … engineers and adjacent roles through design decisions, code, and delivery support Improve data sharing, onboarding of new data sources, and interoperability across teams and systems Introduce and evaluate new tools, patterns, and technologies where they genuinely add value - balancing innovation with pragmatism Build robust, production-grade solutions , not proofs ...

Technical Programme Manager - Workstream Lead

Hiring Organisation
Experis
Location
London, United Kingdom
Employment Type
Contract
delivery flow. * Support effective agile ways of working, including planning, ceremonies, prioritisation and delivery discipline. * Manage dependencies across other SAP workstreams, legacy systems, integration points, data migration activities, and third-party suppliers. * Proactively identify, manage, and escalate risks, issues, and decisions, driving timely mitigation and resolution. Assess ...

AWS Data Engineer - SC Cleared

Hiring Organisation
Sanderson Government and Defence
Location
London, United Kingdom
Employment Type
Contract, Work From Home
Contract Rate
£480 - £490 per day
understanding of working in secure, regulated, or classified environments Ability to work effectively within structured delivery frameworks Desirable Experience with large-scale or legacy system migration to cloud Knowledge of data governance, security, and compliance in public sector environments This role offers an immediate start for the right ...

Scrum Master - Active SC, Jira, Agile

Hiring Organisation
Hays Specialist Recruitment Limited
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
£545 - £620 per day
Nice to have: Experience working across large-scale client programmes Familiarity with government digital standards or delivery frameworks Exposure to integrating legacy systems and modern cloud-native platforms (e.g. AWS) Understanding of DevSecOps practices within secure environments Relevant Scrum certifications (CSM, PSM, SAFe Scrum Master ...

Full Stack Developer - .Net

Hiring Organisation
Hays Specialist Recruitment Limited
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
£400 - £410 per day
technical solutions. Nice to have: Experience working in secure or highly regulated environments. Knowledge of secure coding practices and compliance standards. Experience supporting legacy and modern hybrid systems. If you're interested in this role, click 'apply now' to forward an up-to-date copy of your ...

Salesforce Engineer (Financial Services Cloud)

Hiring Organisation
Morson Edge
Location
City of London, London, United Kingdom
Employment Type
Contract
standards, contributing to solution design, and ensuring all changes are appropriately documented and controlled. You will also support integration activity between Salesforce and surrounding systems, using appropriate integration patterns to enable seamless data and process flow across the wider enterprise landscape. Strong collaboration across internal teams and external partners … Cards, DataRaptors, and Integration Procedures) will be highly advantageous, particularly in enterprise-scale implementations. Additional experience integrating Salesforce with external or legacy systems is important, along with exposure to identity and verification tools such as Onfido or Experian being a plus. Relevant Salesforce certifications, including Administrator, Platform ...

Java Developer - Active SC, Java, Oracle WebLogic

Hiring Organisation
Hays
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£400.0 - £425.0 per day + up to £425pd (Inside IR35)
Java Developer Active SC Clearance is essential; NPPV3 would be advantageous Strong expertise in Java 11+ with experience supporting legacy systems Proven experience with Oracle WebLogic 11gR1 or similar Experience developing and supporting PL/SQL Hands-on experience with ElasticSearch development and support Nice to have ...

Avaloq Engineer

Hiring Organisation
Fuel Recruitment
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
GBP 700 Daily
Platform ecosystem, including RM Workbench, Middleware, and digital channels Develop and maintain APIs and event-driven integrations to enable Real Time data exchange across systems Enable seamless data flows to support client 360 views, portfolio insights, and transaction processing Contribute to core banking modernisation by decoupling product and data … layers from Legacy systems Support the implementation of a dynamic operational data layer to enable Real Time data consumption Ensure data quality, consistency, lineage, and compliance with regulatory requirements Enable end-to-end wealth journeys including onboarding, financial planning, portfolio management, and trading Support straight-through processing ...

Data Engineer Lead Role - Hybrid - Banking

Hiring Organisation
GCS
Location
City of London, London, United Kingdom
Employment Type
Contract
Contract Rate
£600 - £700/day Inside IR35
supporting modern data platform, with a particular focus on Databricks, cloud-based data engineering, and leading the migration of legacy Oracle systems into scalable, cloud-native environments. The role supports the organisation's data strategy especially on Finance and Regulatory domain by ensuring high-quality, reliable pipelines … environment management. Ensure governance, performance optimisation. Legacy Oracle Migration Leadership Lead and coordinate the migration of data assets from Oracle database systems to the modern cloud data platform. Oversee source-to-target mapping, data model redesign, and automated migration frameworks. Define strategy for retiring legacy ...

Security Architect - DV Cleared

Hiring Organisation
DATTalent ltd
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
£600 - £625 per day
modernise a core operational platform. Central to this is the design and build of a new, secure application and data environment, replacing a legacy system that has been in place for a number of years. This is a high-stakes programme operating within a sensitive environment. The organisation ...

Xero Trainer / Consultant

Hiring Organisation
Robert Half
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
£400 - £500 per day
essential Strong track record of implementing Xero for small business clients Experience supporting clients through full Xero setup and migrations from legacy systems Ability to troubleshoot and resolve complex Xero-related issues Experience delivering structured training to internal or external stakeholders Excellent communication skills, with the ability ...

Xero Consultant

Hiring Organisation
Robert Half Limited
Location
South East London, London, United Kingdom
Employment Type
Contract
Contract Rate
£400 - £500 per day
essential Strong track record of implementing Xero for small business clients Experience supporting clients through full Xero setup and migrations from legacy systems Ability to troubleshoot and resolve complex Xero-related issues Experience delivering structured training to internal or external stakeholders Excellent communication skills, with the ability ...

Boomi Developer

Hiring Organisation
BOSS Professional Services LTD
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
£575 - £675 per day
Specific Experience (Highly Desirable) Whilst ERP experience is a must, direct experience building integrations out of Infor LN (or legacy Baan systems). Familiarity with Infor LN’s database schemas and functional tables (Finance, Logistics, Procurement, Warehousing, or Manufacturing modules). Understanding of how Infor LN interacts ...

ERP Data Migration Lead Outside IR35

Hiring Organisation
Cathcart Technology
Location
City of London, London, Bishopsgate, United Kingdom
Employment Type
Contract
Contract Rate
£600 - £650/day
readiness across all domains, delivery phases, and regions. This will include the delivery of data from the various, internationally disparate legacy IT systems (including SAP R3/BO) to the new IFS solution. Both a business data workstream and a technical IFS data migration workstream ...

Full Stack Developer - Python/React/Javascript

Hiring Organisation
REAL Technical Solutions Limited
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
GBP Daily
cloud-based securities processing platform used by global institutions. This role focuses on data integration, migration and modernisation, connecting cloud platforms with complex Legacy systems. Role Description: The PTP Platform is a leading-edge, cloud-based Securities Processing solution that provides trade life cycle processing for a wide …/Javascript: Financial services/capital markets experience. Knowledge of trade life cycle processing. ETL and data warehouse experience. Docker and Kubernetes exposure. Distributed systems experience (Kafka, microservices, event streaming). Full Stack Developer - Python/React/Javascript Based in the City of London (2 days ...

Cut Over Manager

Hiring Organisation
Hays Specialist Recruitment Limited
Location
Uxbridge, Middlesex, England, United Kingdom
Employment Type
Contractor
Contract Rate
Salary negotiable
execution for a large-scale Oracle Fusion HCM transformation. This role will ensure a controlled, low-risk transition from legacy HR systems into Oracle Cloud, coordinating across multiple work streams and stakeholders. * Location: Uxbridge * Daily Rate: Flexible * Contract Length: Sep 2027 * Start Date: ASAP Key Responsibilities * Develop ...

DBT Architect/Lead Analytics Engineer

Hiring Organisation
GlobalLogic UK&I
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
GBP 35 Annual
/Lead Analytics Engineer, you will be the primary technical authority for our enterprise cloud migration. You will lead the transition from a Legacy Teradata environment to a modern AWS Lakehouse architecture. Your mission is to design the foundational dbt architecture that replaces 500+ complex BTEQ scripts with … macro development, and incremental materialization strategies. Deep experience with Databricks (Unity Catalog, SparkSQL) and Apache Iceberg on AWS S3. Ability to reverse-engineer Legacy Teradata/BTEQ and write highly optimized SQL for Databricks. Hands-on experience with Apache Airflow (ideally Astronomer) for managing complex dependency trees. Strong ...

Change Manager - Financial Crime

Hiring Organisation
Natwest CWS
Location
City of London, London, United Kingdom
Employment Type
Contract, Work From Home
change delivery of a new Customer Monitoring capability as part of a Financial Crime transformation programme, enabling the transition from a legacy rules-based Transaction Monitoring environment to a modern, model-driven and analytics-led platform that strengthens compliance, scalability, and risk detection. What you'll do: Lead … functional delivery across business, technology, operations, and vendor teams to implement the Customer Monitoring capability. Drive the transition from legacy Transaction Monitoring systems to a modern, analytics-led Financial Crime monitoring platform. Ensure successful delivery of change initiatives that meet regulatory, risk, and compliance requirements. Oversee ...

Change Manager - Financial Crime

Hiring Organisation
NatWest CWS
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
Salary negotiable
change delivery of a new Customer Monitoring capability as part of a Financial Crime transformation programme, enabling the transition from a legacy rules-based Transaction Monitoring environment to a modern, model-driven and analytics-led platform that strengthens compliance, scalability, and risk detection. What you'll do: Lead … functional delivery across business, technology, operations, and vendor teams to implement the Customer Monitoring capability. Drive the transition from legacy Transaction Monitoring systems to a modern, analytics-led Financial Crime monitoring platform. Ensure successful delivery of change initiatives that meet regulatory, risk, and compliance requirements. Oversee ...

Integration Architect

Hiring Organisation
Atrium Workforce Solutions UK Limited
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
GBP 680 Daily
work with Kafka, SQS, and SNS to enable scalable, resilient, and Real Time integrations. You'll lead integration across Legacy and modern systems, ensuring solutions are secure, observable, scalable, and GDS-compliant. Working closely with cross-functional teams and architects, you'll align on standards, patterns ...

IAM Architect

Hiring Organisation
Red King Resourcing
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£600 - £750/day INSIDE IR35
enables secure digital services, improves user experience, and supports long-term organisational objectives. The organisation currently operates a complex identity ecosystem comprising a legacy Student Information System (SIS), Active Directory, Microsoft Entra ID, and Auth0, with multiple identity stores and overlapping user management processes. Key Responsibilities Lead … technical assessments to understand current-state identity capabilities and challenges. Assess the existing identity architecture, including Active Directory, Microsoft Entra ID, Auth0, and legacy SIS integrations. Define a target-state identity operating model and architecture aligned to business and security requirements. Evaluate identity platform options and market offerings ...

Senior Kotlin Engineer (XP, GCP) - Investment Banking - London

Hiring Organisation
Salt Search
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
£500 - £800 per day
Capital Markets. You will join a high-calibre London-based front office engineering team working on a next-generation issuance platform replacing a legacy bookbuilding system. This is a hands-on engineering role with a strong emphasis on Extreme Programming (XP) practices, including mob programming, test-driven development … store Artifact Registry and Cloud Logging Key Management Experience with CI/CD and SDLC in regulated or enterprise environments Comfortable working on production systems requiring high availability and accuracy Engineers in this role: Work primarily in mobs, sharing ownership of design and code Build, test, and evolve services ...

IAM Specialist

Hiring Organisation
Red King Resourcing
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£600 - £700/day INSIDE IR35
enables secure digital services, improves user experience, and supports long-term organisational objectives. The organisation currently operates a complex identity ecosystem comprising a legacy Student Information System (SIS), Active Directory, Microsoft Entra ID, and Auth0, with multiple identity stores and overlapping user management processes. Key Responsibilities Lead … technical assessments to understand current-state identity capabilities and challenges. Assess the existing identity architecture, including Active Directory, Microsoft Entra ID, Auth0, and legacy SIS integrations. Define a target-state identity operating model and architecture aligned to business and security requirements. Evaluate identity platform options and market offerings ...