Date posted
Commute time
Locations
Type of Company
Job types
Salaries
Locations
Locations
Salaries
Date posted
Type of Company
Job types
)
Strong knowledge of the API/integration lifecycle, including design, deployment, and enhancement. * Expertise in RESTful & SOAP API design, APIM policy, and transformations. * Skilled in API/Integration security protocols & best practices. * Practical experience with Postman, API monitoring, and documentation tools. * Knowledge of Open API Specification, WSDL, SOAP, XSLT. * Application Insight proficiency in .NET and .NET Core (Web, API) and working knowledge of VS Code with Azure.
Strong knowledge of the API/integration lifecycle, including design, deployment, and enhancement. * Expertise in RESTful & SOAP API design, APIM policy, and transformations. * Skilled in API/Integration security protocols & best practices. * Practical experience with Postman, API monitoring, and documentation tools. * Knowledge of Open API Specification, WSDL, SOAP, XSLT. * Application Insight proficiency in .NET and .NET Core (Web, API) and working knowledge of VS Code with Azure.
NEW
Solution Architect - Location: Windsor, UK (Hybrid 1 day per week onsite) Type: Contract (6 months) | Rate: £500/day (Inside IR35) Start Date: 15 September 2025 - About the Role - Our client, a leading global organization, is seeking an experienced Solution Architect to play a key role in shaping and delivering scalable, secure, and efficient solutions within a large-scale transformation programme. You will be responsible for defining technology roadmaps, ensuring architectural best practices, and collaborating with stakeholders across business and IT functions. This is a hands-on, strategic role requiring strong architecture expertise, particularly in AWS integration, application hosting, governance, and security roadmaps, with the ability to influence at senior levels and guide implementation teams. Key Responsibilities
Solution Architect - Location: Windsor, UK (Hybrid 1 day per week onsite) Type: Contract (6 months) | Rate: £500/day (Inside IR35) Start Date: 15 September 2025 - About the Role - Our client, a leading global organization, is seeking an experienced Solution Architect to play a key role in shaping and delivering scalable, secure, and efficient solutions within a large-scale transformation programme. You will be responsible for defining technology roadmaps, ensuring architectural best practices, and collaborating with stakeholders across business and IT functions. This is a hands-on, strategic role requiring strong architecture expertise, particularly in AWS integration, application hosting, governance, and security roadmaps, with the ability to influence at senior levels and guide implementation teams. Key Responsibilities
NEW
)
Full Stack Engineer, GraphQL APIs, TypeScript, Node
Full Stack Engineer, GraphQL APIs, TypeScript, Node
Staffworx Limited
Brentford End, TW7
market rates, outside IR35, 6 months initial, 2 days week on site
Full Stack Software Engineer GraphQL | TypeScript | Cloud-Native - Based West London, Hybrid working, 1-2 days week on site. Outside IR35. 6 months initial, likely extensions. Were looking for aFull Stack Software Engineerwho loves building high-quality, scalable systems and isn't afraid to get deep into both the code and the infrastructure. If GraphQL APIs, TypeScript/Node.js backends and cloud-native deployments make you feel right at home, this is your stage. What you ll be doing * Design & buildrobust, scalableTypeScript/Node.jsservices andGraphQL APIsthat power real-world applications. * Write code that lastsclean, maintainable, well-tested, and resilient. * Shape our infrastructurethrough modern DevOps practices: CI/CD pipelines (Jenkins, Concourse), containerisation, Helm, and Kubernetes deployments.
Full Stack Software Engineer GraphQL | TypeScript | Cloud-Native - Based West London, Hybrid working, 1-2 days week on site. Outside IR35. 6 months initial, likely extensions. Were looking for aFull Stack Software Engineerwho loves building high-quality, scalable systems and isn't afraid to get deep into both the code and the infrastructure. If GraphQL APIs, TypeScript/Node.js backends and cloud-native deployments make you feel right at home, this is your stage. What you ll be doing * Design & buildrobust, scalableTypeScript/Node.jsservices andGraphQL APIsthat power real-world applications. * Write code that lastsclean, maintainable, well-tested, and resilient. * Shape our infrastructurethrough modern DevOps practices: CI/CD pipelines (Jenkins, Concourse), containerisation, Helm, and Kubernetes deployments.
Job Title: Salesforce Vlocity Developer - Location: Windsor, UK (Hybrid 1 day per week onsite) Contract Duration: 6 Months - Day Rate: £500 Inside IR35 - About the Role - We are looking for an experienced Salesforce Vlocity Developer to join a major business unit on a 6-month contract. This is a hybrid role requiring weekly onsite presence in Windsor, offering an exciting opportunity to work on cutting-edge Salesforce solutions within a collaborative team environment. Key Responsibilities * Design and develop custom Vlocity solutions on the Salesforce platform, including CPQ, CLM, and OmniStudio. * Translate business and product requirements into technical specifications. * Build and maintain Vlocity data models, including objects, fields, and relationships. * Develop custom Apex classes, triggers, and Lightning Web Components.
Job Title: Salesforce Vlocity Developer - Location: Windsor, UK (Hybrid 1 day per week onsite) Contract Duration: 6 Months - Day Rate: £500 Inside IR35 - About the Role - We are looking for an experienced Salesforce Vlocity Developer to join a major business unit on a 6-month contract. This is a hybrid role requiring weekly onsite presence in Windsor, offering an exciting opportunity to work on cutting-edge Salesforce solutions within a collaborative team environment. Key Responsibilities * Design and develop custom Vlocity solutions on the Salesforce platform, including CPQ, CLM, and OmniStudio. * Translate business and product requirements into technical specifications. * Build and maintain Vlocity data models, including objects, fields, and relationships. * Develop custom Apex classes, triggers, and Lightning Web Components.
NEW
)
We have an exciting opportunity for a Senior Salesforce Administrator / Developer(Technical Specialist) at NPL. The focus for this role is to lead on the design, development, and support of the platform. Youll be joining the Enterprise Systems team. Salesforce is becoming a crucial business tool within NPL and we require a Snr Salesforce Administrator/Developer(Technical Specialist) to support the adoption within the business. The person will be required to collaborate withkey stakeholders in the organisation, including Sales, Marketing, Commercial Excellence,business analysts,project managersand end-users to gather and analyse their business needs and requirements, and to consequently drive the development of the Salesforce platform in response to those needs to meet strategic objectives. This role will be looked upon to execute and lead on technical implementations
We have an exciting opportunity for a Senior Salesforce Administrator / Developer(Technical Specialist) at NPL. The focus for this role is to lead on the design, development, and support of the platform. Youll be joining the Enterprise Systems team. Salesforce is becoming a crucial business tool within NPL and we require a Snr Salesforce Administrator/Developer(Technical Specialist) to support the adoption within the business. The person will be required to collaborate withkey stakeholders in the organisation, including Sales, Marketing, Commercial Excellence,business analysts,project managersand end-users to gather and analyse their business needs and requirements, and to consequently drive the development of the Salesforce platform in response to those needs to meet strategic objectives. This role will be looked upon to execute and lead on technical implementations
NEWFEATURED
)
Hybrid Python Developer – 9-12 Month Contract (Outside IR35)
Hybrid Python Developer – 9-12 Month Contract (Outside IR35)
Halian Technology Limited
RG1, Reading
From £375 to £450 per day
HybridPython Developer 9-12 Month Contract (Outside IR35) * Location: Hybrid (1 day a week in London, UK) * Contract Duration: 9-12 months * Rate: £375-£450 per day (Outside IR35) Exciting Projects: Work on innovative digital solutions in a start-up environment. Flexible Working: Enjoy a hybrid role with one day a week in London. Collaborative Culture: Be part of a talented, supportive team that values your input. We are recruiting on behalf of an innovative Insurance company looking for experienced Python Developers. This is an excellent opportunity for experienced developers eager to work on exciting projects in a dynamic and fast-paced environment. Our client is a rapidly expanding start-up backed by a major insurer and specialising in pay-as-you-go car insurance growing quicklywith over a million customers.
HybridPython Developer 9-12 Month Contract (Outside IR35) * Location: Hybrid (1 day a week in London, UK) * Contract Duration: 9-12 months * Rate: £375-£450 per day (Outside IR35) Exciting Projects: Work on innovative digital solutions in a start-up environment. Flexible Working: Enjoy a hybrid role with one day a week in London. Collaborative Culture: Be part of a talented, supportive team that values your input. We are recruiting on behalf of an innovative Insurance company looking for experienced Python Developers. This is an excellent opportunity for experienced developers eager to work on exciting projects in a dynamic and fast-paced environment. Our client is a rapidly expanding start-up backed by a major insurer and specialising in pay-as-you-go car insurance growing quicklywith over a million customers.
NEW
)
Job Description Workday Integration Consultant - Key Responsibilities - Design, develop, and maintain Workday integrations including Core Connectors, EIBs, Studio, and custom solutions. Leverage Workday HCM core knowledge to deliver effective integration solutions. Perform XML/XSLT transformations and handle various file formats (CSV, XML, JSON, etc.). Work with APIs, Web Services (SOAP/REST), and file transfer protocols (SFTP/FTP). Ensure accuracy, compliance, and performance of integrations across HR, Payroll, Benefits, and Finance systems. Collaborate with business stakeholders to translate requirements and process logic into actionable code and functional solutions. Troubleshoot, optimize, and support integrations in production environments. Plan, prioritize, and deliver assigned work within agreed timelines. Required Skills & Qualifications
Job Description Workday Integration Consultant - Key Responsibilities - Design, develop, and maintain Workday integrations including Core Connectors, EIBs, Studio, and custom solutions. Leverage Workday HCM core knowledge to deliver effective integration solutions. Perform XML/XSLT transformations and handle various file formats (CSV, XML, JSON, etc.). Work with APIs, Web Services (SOAP/REST), and file transfer protocols (SFTP/FTP). Ensure accuracy, compliance, and performance of integrations across HR, Payroll, Benefits, and Finance systems. Collaborate with business stakeholders to translate requirements and process logic into actionable code and functional solutions. Troubleshoot, optimize, and support integrations in production environments. Plan, prioritize, and deliver assigned work within agreed timelines. Required Skills & Qualifications
Company Description - Founded by experienced entrepreneurs and engineers in 2016, Pismo is a technology company that provides a comprehensive processing platform for banking, card issuing and financial market infrastructure and helps customers innovate and build the next generation of banking and payment solutions. Pismo joined Visa in 2024. Leveraging Visas solutions, our core platform, and an expanding suite of capabilities, Pismo addresses the technological challenges that large banks, marketplaces, and fintech companies face in migrating from legacy systems to more advanced technology in the market. Pismos cloud-based platform empowers firms to build and launch financial products rapidly, scaling as they grow to have a broader audience while keeping high security and availability standards. Pismos 500+ employees are located in more than 10 countries around the wor
Company Description - Founded by experienced entrepreneurs and engineers in 2016, Pismo is a technology company that provides a comprehensive processing platform for banking, card issuing and financial market infrastructure and helps customers innovate and build the next generation of banking and payment solutions. Pismo joined Visa in 2024. Leveraging Visas solutions, our core platform, and an expanding suite of capabilities, Pismo addresses the technological challenges that large banks, marketplaces, and fintech companies face in migrating from legacy systems to more advanced technology in the market. Pismos cloud-based platform empowers firms to build and launch financial products rapidly, scaling as they grow to have a broader audience while keeping high security and availability standards. Pismos 500+ employees are located in more than 10 countries around the wor
Knowledge of HSE, Safety and Global Plant Layout practices (i.e., PIP, API, GAP, etc.)
Knowledge of HSE, Safety and Global Plant Layout practices (i.e., PIP, API, GAP, etc.)
All relevant international Codes and API/ISO standards for equipment installed on packages in both FEED and EPC environments.
All relevant international Codes and API/ISO standards for equipment installed on packages in both FEED and EPC environments.
Any company can tell you about how they are a multi award winning, market leading business and yes, we are both of those things in the world of IoT connectivity! But we're more than that. Our mission? To make IoT management a breeze for any device, anywhere. With over 10 million IoT subscriptions active in 165 countries and direct partnerships with 50 mobile networks , we connect you to more than 750 networks worldwide, delivering unmatched value across the IoT connectivity chain. Innovation is in our DNA , and we have an insatiable hunger to 'wow'! While we may not always get it right, our drive to collaborate, innovate, and achieve top-notch customer satisfaction never wavers. We offer industry expertise, stellar service support, and the most flexible, resilient, and secure connectivity solutions on the market.
Any company can tell you about how they are a multi award winning, market leading business and yes, we are both of those things in the world of IoT connectivity! But we're more than that. Our mission? To make IoT management a breeze for any device, anywhere. With over 10 million IoT subscriptions active in 165 countries and direct partnerships with 50 mobile networks , we connect you to more than 750 networks worldwide, delivering unmatched value across the IoT connectivity chain. Innovation is in our DNA , and we have an insatiable hunger to 'wow'! While we may not always get it right, our drive to collaborate, innovate, and achieve top-notch customer satisfaction never wavers. We offer industry expertise, stellar service support, and the most flexible, resilient, and secure connectivity solutions on the market.
We are seeking a skilled SAP Data Migration Specialist to join our team. This contract role sits inside IR35. Duration 6 months - Summary - The successful candidate will have experience in S4 Hana Greenfield data migration and multi LOBs such as Finance, Procurement, Manufacturing and Projects. This role requires meticulous attention to detail, a strong ability to work independently while supporting the team, and effective communications skills for collaboration with Business Users. Key Tasks * Develop and optimize SQL scripts for data extraction, transformation, loading (ETL). * Write robust, efficient, and scalable SQL code for data manipulation, reporting, and analytics across various platforms * Proficiency in writing complex SQL queries, stored procedures, and database triggers * Experienced S/4HANA Public cloud Data Migration consultant covering P2P, OTC, Financ
We are seeking a skilled SAP Data Migration Specialist to join our team. This contract role sits inside IR35. Duration 6 months - Summary - The successful candidate will have experience in S4 Hana Greenfield data migration and multi LOBs such as Finance, Procurement, Manufacturing and Projects. This role requires meticulous attention to detail, a strong ability to work independently while supporting the team, and effective communications skills for collaboration with Business Users. Key Tasks * Develop and optimize SQL scripts for data extraction, transformation, loading (ETL). * Write robust, efficient, and scalable SQL code for data manipulation, reporting, and analytics across various platforms * Proficiency in writing complex SQL queries, stored procedures, and database triggers * Experienced S/4HANA Public cloud Data Migration consultant covering P2P, OTC, Financ
Any company can tell you about how they are a multi award winning, market leading business and yes, we are both of those things in the world of IoT connectivity! But we're more than that. Our mission? To make IoT management a breeze for any device, anywhere. With over 14 million IoT subscriptions active in 165 countries and direct partnerships with 50 mobile networks , we connect you to more than 750 networks worldwide, delivering unmatched value across the IoT connectivity chain. Innovation is in our DNA , and we have an insatiable hunger to 'wow'! While we may not always get it right, our drive to collaborate, innovate, and achieve top-notch customer satisfaction never wavers. We offer industry expertise, stellar service support, and the most flexible, resilient, and secure connectivity solutions on the market.
Any company can tell you about how they are a multi award winning, market leading business and yes, we are both of those things in the world of IoT connectivity! But we're more than that. Our mission? To make IoT management a breeze for any device, anywhere. With over 14 million IoT subscriptions active in 165 countries and direct partnerships with 50 mobile networks , we connect you to more than 750 networks worldwide, delivering unmatched value across the IoT connectivity chain. Innovation is in our DNA , and we have an insatiable hunger to 'wow'! While we may not always get it right, our drive to collaborate, innovate, and achieve top-notch customer satisfaction never wavers. We offer industry expertise, stellar service support, and the most flexible, resilient, and secure connectivity solutions on the market.
Key Accounts - Contact Centre as a Service Support Engineer
Key Accounts - Contact Centre as a Service Support Engineer
Babble Cloud Limited
Reading, Berkshire
Competitive
Company Description - Why Babble? Babble is a Customer Experience-led growth business. As the ultimate Trusted Advisor for cloud-based technologies, we specialize in empowering businesses with the best solutions from the world's leading providers. * Microsoft Modern Work * Cybersecurity * Contact Centre Technology * Mobile Solutions * Communications & Connectivity - With nearly 15,000 customers, we're just scratching the surface of our potential. Many of our clients currently benefit from one or two of our technologies, presenting an incredible opportunity to introduce them to our full suite of market-leading solutions. Join us on this exciting journey and let's achieve greatness together! About Us | Leading UK Cloud Solutions Provider | Babble - Job Description - Join Our Dynamic Team as a Key Accounts - Contact Centre as a Service Support Engineer! Are you passionat
Company Description - Why Babble? Babble is a Customer Experience-led growth business. As the ultimate Trusted Advisor for cloud-based technologies, we specialize in empowering businesses with the best solutions from the world's leading providers. * Microsoft Modern Work * Cybersecurity * Contact Centre Technology * Mobile Solutions * Communications & Connectivity - With nearly 15,000 customers, we're just scratching the surface of our potential. Many of our clients currently benefit from one or two of our technologies, presenting an incredible opportunity to introduce them to our full suite of market-leading solutions. Join us on this exciting journey and let's achieve greatness together! About Us | Leading UK Cloud Solutions Provider | Babble - Job Description - Join Our Dynamic Team as a Key Accounts - Contact Centre as a Service Support Engineer! Are you passionat
Proficiency in API technologies, including RESTful APIs and platforms such as Apigee, with the ability to lead teams in designing robust and secure integration architectures.
Proficiency in API technologies, including RESTful APIs and platforms such as Apigee, with the ability to lead teams in designing robust and secure integration architectures.
350 exact matches jobs are outside your preferred location
)
A top-tier defense organization is looking for an experienced Axway API Developer / Administrator to join their team on a 6-month contract. * Axway's core products: Policy Studio, API Gateway, and API Manager. If you are an experienced professional with a background in API, MFT, or secure file transfers, this could be the perfect opportunity for you.
A top-tier defense organization is looking for an experienced Axway API Developer / Administrator to join their team on a 6-month contract. * Axway's core products: Policy Studio, API Gateway, and API Manager. If you are an experienced professional with a background in API, MFT, or secure file transfers, this could be the perfect opportunity for you.
NEWFEATURED
Senior API Technical Consultant (GraphQL Specialist)
Senior API Technical Consultant (GraphQL Specialist)
Staffworx Limited
London
market rates, outside IR35, 2 days on site
Lead the designand evolution of our API schemas, ensuring they meet the complex demands of a rapidly growing platform. * Expert levelGraphQL, including advanced API design, schema evolution, performance optimisation.
Lead the designand evolution of our API schemas, ensuring they meet the complex demands of a rapidly growing platform. * Expert levelGraphQL, including advanced API design, schema evolution, performance optimisation.
)
Up to £515 per day (Inside IR35) Remote / must be UK based - 12 months - My client is an instantly recognisable consultancy who seek a Senior Integration Developer, with active SC clearance and experience in Microsoft Dynamics 365 Finance, to lead the design and implementation of robust, secure, and scalable integrations for an end client. * Hands-on experience as a Senior Integration Developer, with D365 Finance integrations. * Active Security Clearance (SC) * Deep knowledge of REST APIs, OData, DMF packages, and data mapping (XSLT, XML, JSON, CSV). * Proficiency in tools like Postman, Azure Logic Apps, PowerShell, and C#. * Experience with ETL processes, error handling, idempotency, and throttling. * Strong understanding of secure data handling, encryption, and compliance standards. * Familiarity with monitoring tools like Application Insights and Log Analytics.
Up to £515 per day (Inside IR35) Remote / must be UK based - 12 months - My client is an instantly recognisable consultancy who seek a Senior Integration Developer, with active SC clearance and experience in Microsoft Dynamics 365 Finance, to lead the design and implementation of robust, secure, and scalable integrations for an end client. * Hands-on experience as a Senior Integration Developer, with D365 Finance integrations. * Active Security Clearance (SC) * Deep knowledge of REST APIs, OData, DMF packages, and data mapping (XSLT, XML, JSON, CSV). * Proficiency in tools like Postman, Azure Logic Apps, PowerShell, and C#. * Experience with ETL processes, error handling, idempotency, and throttling. * Strong understanding of secure data handling, encryption, and compliance standards. * Familiarity with monitoring tools like Application Insights and Log Analytics.
NEW
Up to £515 per day (Inside IR35) Remote / must be UK based - 3 months initially (open to extension) My client is an instantly recognisable consultancy who seek a - to lead the design and implementation of robust, secure, and scalable integrations for an end client. * Hands-on experience as a Senior Integration Developer, with D365 Finance integrations. * Deep knowledge of REST APIs, OData, DMF packages, and data mapping (XSLT, XML, JSON, CSV). * Proficiency in tools like Postman, Azure Logic Apps, PowerShell, and C#. * Experience with ETL processes, error handling, idempotency, and throttling. * Strong understanding of secure data handling, encryption, and compliance standards. * Familiarity with monitoring tools like Application Insights and Log Analytics. * Industry experience within financial services * Experience with Microsoft Power Platform (Power Automate, Powe
Up to £515 per day (Inside IR35) Remote / must be UK based - 3 months initially (open to extension) My client is an instantly recognisable consultancy who seek a - to lead the design and implementation of robust, secure, and scalable integrations for an end client. * Hands-on experience as a Senior Integration Developer, with D365 Finance integrations. * Deep knowledge of REST APIs, OData, DMF packages, and data mapping (XSLT, XML, JSON, CSV). * Proficiency in tools like Postman, Azure Logic Apps, PowerShell, and C#. * Experience with ETL processes, error handling, idempotency, and throttling. * Strong understanding of secure data handling, encryption, and compliance standards. * Familiarity with monitoring tools like Application Insights and Log Analytics. * Industry experience within financial services * Experience with Microsoft Power Platform (Power Automate, Powe
NEW
)
Business Analyst, Data Integration, Order Fulfilment
Business Analyst, Data Integration, Order Fulfilment
Harvey Nash
London
£600 - £650 per day + Inside IR35
£600- £650pd via Umbrella London (Remote) A global technology Financial Services business are currently seeking a Business Analyst to join them on a long term contract in London. The role requires excellent data integration and process change experience, alongside direct order to fulfilment/ order to cash experience. This will be alongside direct Mulesoft or SAP experience. * Experience working as a Business Analyst in a global Financial Services or Technology business * Experience working with SAP or MuleSoft * Excellent Data Integration experience * Direct Order to Fulfilment, Order to Cash experience * Very strong verbal and written communication skills If you meet these requirements please apply for immediate consideration.
£600- £650pd via Umbrella London (Remote) A global technology Financial Services business are currently seeking a Business Analyst to join them on a long term contract in London. The role requires excellent data integration and process change experience, alongside direct order to fulfilment/ order to cash experience. This will be alongside direct Mulesoft or SAP experience. * Experience working as a Business Analyst in a global Financial Services or Technology business * Experience working with SAP or MuleSoft * Excellent Data Integration experience * Direct Order to Fulfilment, Order to Cash experience * Very strong verbal and written communication skills If you meet these requirements please apply for immediate consideration.
NEW
)
Business Analyst, Data Integration, Order Fulfilment
Business Analyst, Data Integration, Order Fulfilment
Harvey Nash
London
£600 - £650 per day + Inside IR35
£600- £650pd via Umbrella London (Remote) A global technology Financial Services business are currently seeking a Business Analyst to join them on a long term contract in London. The role requires excellent data integration and process change experience, alongside direct order to fulfilment/ order to cash experience. This will be alongside direct Mulesoft or SAP experience. * Experience working as a Business Analyst in a global Financial Services or Technology business * Experience working with SAP or MuleSoft * Excellent Data Integration experience * Direct Order to Fulfilment, Order to Cash experience * Very strong verbal and written communication skills If you meet these requirements please apply for immediate consideration.
£600- £650pd via Umbrella London (Remote) A global technology Financial Services business are currently seeking a Business Analyst to join them on a long term contract in London. The role requires excellent data integration and process change experience, alongside direct order to fulfilment/ order to cash experience. This will be alongside direct Mulesoft or SAP experience. * Experience working as a Business Analyst in a global Financial Services or Technology business * Experience working with SAP or MuleSoft * Excellent Data Integration experience * Direct Order to Fulfilment, Order to Cash experience * Very strong verbal and written communication skills If you meet these requirements please apply for immediate consideration.
NEW
)
Azure Analytics & Integration stack (e.g., Databricks, Synapse, Logic Apps, API Management) o API frameworks (SOAP, REST, WebSocket)
Azure Analytics & Integration stack (e.g., Databricks, Synapse, Logic Apps, API Management) o API frameworks (SOAP, REST, WebSocket)
)
Solid experience with Python and FastAPI for backend/API development.
Solid experience with Python and FastAPI for backend/API development.
)
Experience with MuleSoft and API Gateways.
Experience with MuleSoft and API Gateways.
NEW
Previous work in API integration
Previous work in API integration
NEW