Senior web developer hourly rate london jobs

Hi, My name is Junior, i manage a small hotel in London and have recently set up a new website with wix I hope i can get some assistance, We are a hotel and we use wix for our homepage for our website. We us book now buttons on our site to redirect guest to our booking engine which is with , I have set up google analytics but i have no idea if it is tracking correct the data, i also set up google tag manager to get the third cookies from the booking engine, but again i don't think its set up correctly. I need help to make sure everything is set up correctly so i can see the full customer journey and also in google analytics help to find out the data i need once everything is

I'm seeking an advanced C# developer with prior experience in creating desktop applications on Windows. Familiarity with TWAIN integration is crucial. Key Requirements: - Advanced C# Knowledge: The ideal candidate should be comfortable and well-versed in advanced concepts. - Windows Desktop Application Development: Previous experience in developing desktop applications on Windows is a must. - TWAIN Integration: You should have prior experience integrating TWAIN for image scanning functionalities. This is a challenging project that requires a high level of expertise in C# and experience in developing Windows desktop applications, particularly with TWAIN integration. If you're confident in your skills and have a solid track record in similar projects, I'd like to hea...

Looking for a talented React Frontend developer to assist in creating a sophisticated web application. Key requirements: - Proven experience building web applications using React framework - Familiarity with creating intuitive dashboards - Experience implementing authentication features - Ability to integrate a functional chatbot - Detail-oriented and exceptional UI/UX skills - Knowledge in frontend performance optimization Strong applicants will have a depth of experience in the above areas and be ready to hit the ground running. Let's connect to discuss the details further.

...teaching methods to make different Arabic dialects closer than ever and to enable foreign students to speak & communicate in Arabic with different Arab nationalities in the fastest way possible. * Job Summary: We are looking for a Software Developer Freelancer who will help us with the integration of Stripe within our systems. We already configured Stripe and are currently using it for our subscriptions but manually updating the payments in our education management software where we manage students, tutors, schedules, and billing). The software developer will mainly need to focus on automating this existing process to reduce the total time we spend and complexity. * Responsibilities ??‍♀️ 1. Refinement and Planning Refining the integration scope based on the e...

We are seeking a skilled developer with expertise in customizing XFileSharing Pro to enhance our website's payment capabilities. The project involves integrating additional payment options, with a focus on cryptocurrency, and revamping the payment page to accommodate these new options. We also require integration with a third-party payment gateway () to generate custom payment links. If you have experience with XFileSharing Pro, payment gateways, and cryptocurrency processing, we would like to hear from you. Key Requirements: Proven experience with XFileSharing Pro script customization. Expertise in integrating third-party payment gateways. Familiarity with cryptocurrency payment processing. Ability to design and revamp payment pages. Strong understanding of security and best

...providing continuous value to the client? • Business Case: What does the overall business case and financial opportunity to introduce and develop the service from 2025-2030? Please provide as a overview/recommendation for the board. Please assume the following to indicate the Price Point, Pay Back Period and GTM (go to market) strategy (standard fit, optional or subscription models including take rate assumptions) for the overall Safety and Security package. o Volumes 2025: 400,000, increasing 7.5% every year up to and including 2030. o Investment costs: 10% of the overall projected revenue (2025-2030). o Maintenance cost for the overall Safety and Security package will be £50,000 a year with a one-off payment in year 3 of £100,000. o Retailer margins are 5% ...

...Operations – Technical Writing team writes and publishes technical documents and associated content for products and solutions. The team is responsible for articulating complex technical concepts and tasks through simple descriptions and instructions. We are looking for a Senior Technical Writer with a passion for writing and technology, strong communication skills, and a progressive outlook. You will be creative and innovative, curious and willing to learn, and wanting to make a difference. You will work directly with senior management to help us research and transform complex technical concepts, specifications, and procedures into user-oriented information for non-technical and technical audiences for developing high-quality software documentation that meets user ...

I'm in need of an ASP.NET developer to help me implement user authentication, database integration, and file uploading functionalities for a small project. Below are the details of the project requirements: - User Authentication: The system should allow users to register using their email and create a password. They should also be able to log in using the same credentials. - Database Integration: I need the system to store user profiles, transactional records, and product or service listings. The database should be seamlessly integrated with the ASP.NET application. - File Uploading: The project involves a file uploading feature. Users should be able to upload files to the system. I'm looking for someone with experience in ASP.NET development, particularly in implemen...

I recently purchased the Lavarel Hyip Pro Script on Codecanyon. I'm looking for a skilled developer who has experience with this specific script to help me with some customizations. Your main tasks will include: - Adding specific conditions to the Investment Plans section, including the creation of different conditions like F1, F2, etc. - Implementing a ranking system on the platform. - Associating a rate exchange bonus to point and saving it to the database. The ideal freelancer will: - Have prior experience with Lavarel Hyip Pro Script. - Possess a strong understanding of scripting languages as well as database management. - Be able to deliver results quickly, as I'm looking for this project to be completed as soon as possible. Looking forward to receiving y...

I'm in need of a skilled developer to build an efficient gaming marketplace. The platform should be designed to operate similar to with a few specific requirements in mind. Key components of the platform include: - User Registration and Login: The platform should allow for user registration and login with appropriate details, ensuring a personalized experience for users. - Instant Delivery via Email: Upon processing of a purchase, instant delivery of the gaming product should be sent to the user via email. This is a crucial feature that should be handled effectively and securely. - Product Search and Filtering: The platform should have a robust search and filtering system in place to help users easily navigate, search, and find the gaming products they are interested

I'm looking for a skilled frontend developer to help me build a modern, responsive web application. The project requires a deep understanding of HTML, CSS, JavaScript, Angular, and React. Key requirements: - Proficient in HTML, CSS, JavaScript, Angular, and React - Strong experience in developing responsive web applications - Prior experience with implementing user authentication and authorization systems - Capable of integrating animations and transitions in web pages Your role will be to: - Develop a fluid, responsive, and user-friendly web application - Implement user authentication and authorization features - Ensure a seamless and visually appealing user experience with animations and transitions Your expertise in frontend technologies and fr...

I'm in need of a proficient Microsoft power apps developer to create a simple yet functional staff scheduling tracker. The scheduling is related to a consulting business. This involves: - Implement data entry feature to manually enter: employee list (name, role, hourly cost, start date for the specific cost [i.e. the cost of the single employee could change over time]), job list (job name, client, billable value, target margin, start date, job owner [i.e. owner is form employee list], list of employee assigned to the job), list of legal Holiday, company holiday, employee specific holiday - Implementing for each job a view to manually fill, for each employee assigned to that job (i.e. each employee could be assigned to 1 or more jobs), hours to be charged to the specifi...

I'm in need of a proficient web developer to construct a lively online platform, focus being to spotlight and exchange HTML, CSS, and JavaScript projects. The platform will be a hotspot for developers to flaunt their skills, communicate and brainstorm on various front-end projects. Key Features: - Development of User profiles: This will include a detailed assessment of users' skills to provide a comprehensive view of their abilities. Evaluation Protocol: - The users' front-end skills will be ascertained and demonstrated via pertinent certifications and badges earned. This implies that the platform needs a functionality to issue and display these achievements. Skills and experience: - Proficiency in HTML, CSS, and JavaScript. - Past experience in developing ...

I'm looking for a Unity 3D developer to create a mobile action game. Key Project Details: - Game Type: The game will be an action-packed experience - Platform: The target platform for the game is mobile devices Special Requirements: - In-App Purchases: The game will have a in-App purchase system. - Dynamic Maps: The game should have a map that changes every so often. Ideal Skills and Experience: - Proficient in Unity 3D development - Experience in mobile game development - Familiarity with implementing in-app purchases - Ability to create dynamic game maps. If you have the right experience in game development and Unity 3D, feel free to bid on this project.

...on the needs of my website and due to costs, I do not necessarily need a super website made of scratch, a good template (I got envato premium with lots of templates) , I only need it to be secure to got a nice website or a WIX service, SQUARESPACE can be used if it is easier for you and match the requeriments, better for costs. or we can use some envato tempaltes i just got a few nice, web designer-developer will suggest best option based in money and needs. EXAMPLES i like this I just need a website with my portfolio displayed in a nice way and a contact form

I'm seeking a proficient Full Stack Java Developer to create a web application. Even though I haven't specified the use of certain frameworks, familiarity with Spring Boot, Hibernate, and Angular will be useful. Your primary role will focus on: - Developing a highly responsive web application from scratch. - Implementing MySQL as the preferred database management system. Candidates who have prior experience in full-stack development and database management using MySQL are highly desirable. This is a project that demands robust technical skills, so a sound understanding of various Java frameworks and web application development is essential.

Here's some information on how the API calls on how the "idToken" is received. Step 1 Login Flow & API call: 1. On the web page, Fill up the email & password on the login page. Press on "login" 2. A POST API call is made to "" with returns set-cookies in the response header. It contains the "APPSESSID" cookie. This cookie will be used in the next API call. Step 2 On the web page, Once you've landed on the homepage, Click on "Competitions" in the navigation tabs on the Left: 1. This would make a POST API call to "" which uses the "APPSESSID" cookie mentioned above. 2. The response of this API call should return "idToken" as one of the field Here are the Acceptance Criteria...

I have a single page website in progress, utilizing HTML and Bootstrap. I am looking for a skilled developer to finish the Single webpage developed. The webpage is partially completed. Ideal skills and experience: - Proficient in HTML and Bootstrap - Good understanding of responsive design Tasks may include, but not limited to: - Completing unfinished coding - Possibly adding new functionalities - Fixing any existing bugs that might be identified SIMPLE 1 DAY WORK, Need fast person no time wasters

I'm in immediate need of a highly skilled React Native developer with experience in PHP to urgently address and fix issues with expo-notifications in our project. We have a critical demo scheduled for 9 AM EST tomorrow. The selected developer must be able to start immediately, use a time tracker for all billed hours, and ensure the solution is fully functional by the deadline. Please apply only if you have specific expertise in React Native and PHP, and can work efficiently under tight deadlines. Direct experience with expo-notifications is a must. No inefficiencies or unnecessary complexities - straight to the point execution needed.

I need a skilled Java developer specializing in back-end development who can use MySQL as their database technology. The main task for the developer is to work on API development, ensuring the smooth transaction of data between the server and our end users. Ideal Skills and Experience: - Proficient in Java and backend development - Extensive experience with MySQL database technologies - Experience in API development and management

I require an experienced React Native developer for a full-time role. This position is focused on mobile app development for both iOS and Android platforms. A uniquely qualified candidate will have: - Expertise in React Native and mobile development - Strong understanding of UI/UX design - Familiarity with API integration In this role, you will be working according to the detailed design and requirements provided. This is a challenging yet rewarding opportunity to showcase your development skills as you help bring our mobile application to the next level.

I'm seeking an expert in Excel and VBA who can work on an an existing financial model. The primary tasks will involve optimizing formulas, macros, and implementing data validation. I am looking for an hourly regular working engagement where the person will sit with me from time to time online and solve for things one at a time. I cant share workbooks as I have some IP related restrictions so person will have to work on my system, remotely. For Faridabad, Haryana based freelancers, we can do it in physical mode too. Key areas of focus will be: - Refining Formulas and Calculations. - Improving Data Organization and Management - Managing , improving the existing VBAs

I'm looking for a skilled Swift developer to assist me with the creation of a user-friendly iPhone application. The main tasks would involve iOS app development and UI/UX design. The app is intended to be relatively straightforward, focusing on simplicity and ease of use. Key requirements: - Proficiency in Swift - Experience with iOS app development - Ability to create simple, intuitive UI/UX designs This project would be ideal for a developer with a good eye for design and a passion for creating user-friendly applications.

I will be choosing someone one hour from now. Answer me this questions: Are you available immediately? We have a demo tomorrow 9am EST What is your experience with PHP? What AI tools do you use to make your devleopment faster? Are you comfortable working hourly?

I am writing with excitement and a bit of nervousness as I'm on the brink of publishing my own app. It's been a labor of love, and now I'm eager to share it with the world. However, navigating the process of publishing an app can be a bit daunting, and I find myself in need of some guidance. I know you're experienced in this field, and I admire your expertise. Would you be willing to spare some time to lend me your insights and possibly assist me through this process? Your support would mean the world to me, and I am genuinely grateful for any assistance you can offer. Thank you for considering my request. Yours regard. Alok

I need a talented senior React JS developer to take over the front-end development of my project. I need help to create a responsive ui based on screen resolution. Which will bind the email address as in Outlook view Key Tasks: - Handling front-end development effectively - Implementing high quality user interfaces Skills & Experience: - At least 5 years of experience with React JS - Proficiency in Redux is a must - Familiarity with RESTful APIs would be a great advantage

I'm looking for a Django expert skilled in website development. My project is an E-Parking solution, and although I've managed to do most of it, I need some additional features added. Primary Responsibilities: - Add features to existing E-Parking solution Ideal candidates should possess a strong background in Django and a good understanding of database management and API integration. Experience with developing E-Parking solutions or similar will be a great advantage. You should be able to understand my requirements clearly and work efficiently to implement these features to my satisfaction.

...Requirements: - Experience in real estate wholesaling or similar field - Ability to handle the entire acquisition process independently - Proficiency in deal analysis and negotiation - Strong communication and organizational skills - Access to necessary tools and resources for skip tracing and cold calling - Ability to record calls for accountability purposes Payment: We are offering a compensation rate of $1 per hour for a minimum of 20 hours per week at the start, with the potential for higher pay after the business closes its first deal. Please only apply if this arrangement is acceptable to you. If you are interested and meet the requirements, please submit your proposal detailing your relevant experience and how you plan to handle the tasks mentioned above. We look forwar...

We require an experienced WHMCS PHP programmer with knowledge in WHMCS design to rectify issues with our custom front end. The drawbacks we are facing pertain to: - Navigation glitches: We are specifically having issues accessing certain sections of the platform. - Design inconsistencies: The layout of our site seems to be inconsistent across various pages. - Functionality errors: Althou... - Functionality errors: Although not detailed, we are experiencing significant functionality problems. The ideal candidate for this role should be detail-oriented, have excellent debugging skills, and a solid background in WHMCS interface customization. Please specify your experience with WHMCS in your proposal. We require a skilled WHMCS Programmer who can fix the issues we are facing, on Hourly...

I''m looking for ​an expert ​in Canadian pensions ​and personal tax, with full knowledge of CPP, OAS, GIS, ​and BC Senior Supplement benefits. I​ am not looking for generic or investment advice, but personalized consulting at an hourly rate by video. ​You would advise me between these two scenarios: whether I should take the OAS and GIS now and defer my drawdowns of RRSP and LIRA, or defer OAS to age 70 and draw down my RRSP now, based on income and tax projections. You must have financial modelling skills and have done this kind of analysis before. You must have excellent English skills. I will require you to participate in a preliminary voice interview, for which I may pay. Reply with your non-binding estimate of for how many hours of work you think this ...

As a client, I'm looking for an experienced developer to create a comprehensive WordPress plugin for cargo logistics and warehouse rental. The emphasis will be on the shipment tracking feature within this plugin. The main feature of this plugin is Cargo Logistic, focusing on detailed shipment tracking. This feature should provide a comprehensive view of the shipment's journey, including its current location and expected delays & the warehouse rental fees Features: Shipment Management,Shipment Status Update,Shipping Charges,Shipment Tracking Shipment Documents,Shipment Labels,Excel Import and Export,Multiple Shipment Management Users and Permissions,Internal Messaging,Shipment Barcode,Payment Gateways Global Configurations,Shipping Rate,Proof of Delivery,Bulk S...

We have a server of rohan some one using packets or ddos to crash ure server

I'm in search of a developer proficient in PHP, React JS, and Python to help me create a dynamic and interactive web application. Key Responsibilities: - The main task will be website development, focusing on creating an interactive web application. Ideal Skills and Experience: - Proficiency in PHP, React JS, and Python. - Previous experience developing interactive web applications. - Understanding of UI/UX principles for crafting engaging user experiences. The web application will primarily serve as an interactive platform, so prior experience in developing similar applications will be a big plus.

Hi, I'm looking for someone who can write script to automate daily data importing from csv files into a google sheet. We use a new google sheet each week to calculate production for each day, see example here: We have two online platforms that ...attached - the one ending in "new_" is the retail report, the other the wholesale report. I need the final process to be simple for my kitchen team to use ideally with a user interface where they can complete the data import without accessing code, they will select the date that the product in each report relates to, whether it's wholesale or retail, and upload the report. Happy to negotiate rate as I'm not certain of the size of this project.

I will be choosing someone one hour from now. Answer me this questions: Are you available immediately? What is your experience with react native? What AI tools do you use to make your devleopment faster? Are you comfortable working hourly?

We are seeking an experienced web developer to create an advanced instant quote form on our WordPress-based trucking company website. The form will integrate Google Maps for autocomplete suggestions and pull real-time data from Google Sheets to provide visitors with instant truckload quotes. Key Features Required: Google Maps Integration: Autocomplete suggestions for 'Pickup City, State' and 'Delivery City, State' using Google Maps API. Google Sheets Integration: Dynamically pull data from a Google Sheet that includes truckload rates, which are updated weekly. The data includes Pickup and Delivery points, Dead head radius, Max weight, Rate, and Rate per mile. Form Requirements: Fields for Pickup City, State; Delivery City, State; Pickup ...

I am in need of a skilled developer to create an educational app for the iOS platform. Key Requirements: - Your primary task will be developing a feature-rich educational iOS app. - The app is intended to serve as a learning tool, so it should be user-friendly, engaging, and interactive. - I would like the app to have the capability of including quizzes and information boxes. These features are key to creating an effective learning platform. - Prior experience in educational app development will be a plus. Ideal Skills and Experience: - Proficiency in iOS app development. - Experience in creating educational apps. - Ability to implement interactive features like quizzes. - A keen eye for user interface design to ensure the app is engaging and easy to navigate. If you are conf...

...12:30am). It should also factor in specific overtime rules for the workplace, including: - Weekly overtime after 40 hours. -All hours on any given workday shall be paid at the straight time rate of pay unless forty (40) hours have already been worked at straight time. No matter the length of route: example- a driver's bid/scheduled route may be 10.8 hours, as long as the employee does not work any additional hours other than those bid/scheduled, they will be compensated at straight time rate of pay unless forty (40) hours have already been worked at straight time. Hours already compensated at the overtime rate will not be considered when calculating overtime after 40 hours in a week. - If performing extra work in addition to the employee's bid/scheduled r...

I'm in need of a skillful full stack web app developer with expert-level knowledge in HTML, JavaScript, and PHP. The primary objective of this project is to develop a comprehensive web application. Key Features: - Display Business Services - Sell Products Online - Collect User Data through Forms - Provide Content - Job Portal These features should seamlessly combine to create a dynamic, user-friendly platform. The web application aims to reach a diverse range of users including the general public, business professionals, and job seekers but is open to anyone who finds it useful. Ideal candidates must have substantial experience in both front-end and back-end development. I'm looking for someone who can comprehend the project's needs and execut...

As a React Front-End Developer I require a professional who can skillfully incorporate Forms and validation, Dynamic data rendering, Responsive design, along with , CraftJs and MUI libraries into my project. More specifically, the project demands: - Integration of Forms and validation: You must be able to handle complex forms and efficiently implement form validation. - Dynamic data rendering: The project requires handling and displaying dynamic data efficiently. - Responsive design: Your ability to ensure that the design is responsive across various devices. - Implement CraftJs and MUI: You should have experience with these libraries and be able to effectively incorporate them into the project. - Wireframe and Design: I have a ready wireframe and design which you will need to

We're in search of a highly versatile .NET developer for our undisclosed project. While we haven't stated specific skills or project type, candidates should have: - Broad knowledge in .NET and its most popular programming languages (i.e., C# programming, ASP.NET development, and SQL database) - Experience in various .NET projects (i.e., web and desktop applications, as well as enhancement of existing .NET applications) - Proficiency in Windows, Linux, and Mac development platforms Your flexibility and adaptability are our key considerations as project specifics will be discussed upon engagement.

Hi, I require data extraction from 358 scanned Portuguese invoices & receipts: date, vendor, amount. Date: in TEXT format ddmmyyyy (29022024) Vendor name: All in UPPER like ADICAO DISTRIB EXPRESS S/A, ADP COMERCIO DE ALIMENTOS LTDA, APS RESTAURANTE & MERCEARIA EIRELI Amount: in TEXT format 12.345.67 Flat rate 2 NZD per 100 invoices/receipts (Portuguese). Ongoing project opportunity. Please start your bid "2NZD" I appreciate you reading my post

I'm looking for a skilled and efficient Photoshop expert to update my hairstyle in a picture. The primary task is to replace my current braids in the photo with straight hair in my senior quality of the edit should be seamless and realistic. I uploaded a photo of the senior portrait I would like to use (blue background). I also uploaded three reference photos of the altered hair I would like to have. Not sure if this is something somebody could do… Key Requirements: - Proficiency in Photoshop - Experience in hair styling edits - Ability to deliver the edited picture within a day I appreciate your swift response.

...skilled professionals who can: - Effectively engage with these leads via phone - Articulately convey the viability and value of our products - Transition these leads into confirmed sales appointments Given this is not a time-sensitive project, I am open to a flexible working arrangement and encourage the freelancer to take the necessary time to nurture these leads and ensure a high conversion rate. While there is no immediate hurry, I appreciate regular progress reports and updates and leads to be responded to within 30 minutes of them being posted on the app we use for our leads as quicker engagement will allow us to be more likely to be hired for the job. We offer CCTV Installations for homes and business and have 2 main systems to choose from that we sell making it easy an...

I am writing with excitement and a bit of nervousness as I'm on the brink of publishing my own app. It's been a labor of love, and now I'm eager to share it with the world. However, navigating the process of publishing an app can be a bit daunting, and I find myself in need of some guidance. I know you're experienced in this field, and I admire your expertise. Would you be willing to spare some time to lend me your insights and possibly assist me through this process? Your support would mean the world to me, and I am genuinely grateful for any assistance you can offer. Thank you for considering my request. Yours regard. Alok

Cloud Restaurant Website & Mobile App Development I will not be interested in your offer unless I see your Proposals in response to deep reading and understanding of the project requirements (only seniors make bids! The project has a Penalty clause for the deadline) I'm on the lookout for a talented web and mobile app developer who can help bring my cloud restaurant concept to life. Here's what I need: Features: 1. Online Ordering - For easy and convenient customer orders. 2. weekly menu (a page to show our weekly menu) 3. Menu Management - Ability to add, edit, remove, and categorize menu items based on my needs, plus setting item availability. 4. Delivery Tracking - Allowing customers to check their food order status. 5. Nutrition Coaching Reservation - Capa...

~10 php files in stock Rework everything - rewrite texts - change graphics and make it modern corporate. the design requirement is a modern corporate style, one of the main requirements for the landing page is trust the same requirements as for landing pages for affiliate marketers - PPC google ads companies The user must trust the design - the content - aif-usa com a couple of links as an example for additional content The theme of the design must correspond to the direction of the company’s activities: The company is globally engaged in transportation and logistics - WAREHOUSING SERVICES - Import Export operations The company is globally engaged in transportation and logistics - WAREHOUSING SERVICES - Import Export operations One of the company’s projects is the resale...

I need an experienced Python programmer to modify an Instagram comment script I already have. The modifications will primarily focus on comment targeting specificity. Key project tasks: - The script already logs in to multiple Instagram accounts, provided in a file, and writes comments. This functionality is to be preserved. - The main edit entails tailoring the script to target specific user accounts. I want the script to focus its commenting on these specified accounts. - The usernames of these particular accounts will be provided in a file. You must incorporate this file into the script logic to direct commenting activity. Ideal skills for this task: - Proficient in Python scripting. - Previous experience in working with Instagram's API is preferred. - Excellent probl...

...assistance with my site in maintaining, developing and marketing my WordPress website. WordPress Maintenance ( monthly retainer) : I need ongoing, monthly WordPress maintenance to ensure that my site continues to function smoothly. This includes: - Troubleshooting and bug fixes - Plugin updates and compatibility checks - Security monitoring and backups Marketing Strategies (paid hourly) : In addition, I am interested in implementing a comprehensive marketing strategy that includes: - Content Marketing and SEO: Craft engaging content for my site that is also SEO-optimized. - Social Media Marketing: Harness the power of social platforms to reach a wider audience. - Email Campaigns: Cultivate trust and maintain connection with my audience through regular, targeted emails. ...

I'm looking for a skilled Swift developer to help build a small iOS app that will require user authentication and push notifications. Key Requirements: - Develop an iOS app - Implement User Authentication - Integrate Push Notifications - Ensure seamless functionality between the features - Provide support and maintenance post-development The app is intended to be user-friendly and efficient, supporting a smooth login process and real-time notifications. Prior experience in developing similar apps and a good understanding of iOS app development guidelines are highly preferred. Please provide examples of your previous work and any specific expertise you may have in user authentication and push notifications for iOS.