What is a drupal developer仕事

絞り込む

私の最近の検索
次の条件で絞り込む:
予算
to
to
to
種類
スキル
言語
    ジョブステータス
    2,000 what is a drupal developer 仕事が見つかりました。次の価格: USD

    I need an expert developer in Magento, My website has the prices of Argentina with all its taxes, and two languages: Spanish and English. I need it to detect if the IP is abroad, that is, outside Argentina, show other prices (WITHOUT LOCAL TAXES) in both languages

    $128 (Avg Bid)
    $128 平均入札額
    47 入札

    I'm seeking an experienced Fullstack developer well versed in Flutter and FlutterFlow, for the development of an MVP mobile and destokp application, compatible with both iOS and Android. The application must include the following functionalities: - User Authentication - Payment Integration - File Storage - Music Player - Deadline Management and Calendar Utility - Integration with Music Distributors - File Sharing with Variable Access Levels The main objective of this app is to facilitate communication and interaction. Ideal candidates will have extensive experience in the above skill set, a strong understanding of FlutterFlow, and a portfolio showcasing similar completed projects. Important speak spanish.

    $40 / hr (Avg Bid)
    $40 / hr 平均入札額
    82 入札

    I'm looking for a skilled developer who can work with Angular, Node.js, C#, and C++. Unfortunately, I missed answering the question about the project's nature and main goal, but here's an overview of what I need: - You'll be working on a software project that involves these technologies. - Your tasks may include front-end and back-end development, and potentially some native app development. - You must be proficient in all these languages/technologies. Please reach out with your experience in these technologies and a brief overview of any similar projects you've worked on.

    $35 (Avg Bid)
    $35 平均入札額
    15 入札

    I would like to have an urgent abap help over a live call. This is very important we have to sit and program together until we finish. its a long call

    $14 / hr (Avg Bid)
    $14 / hr 平均入札額
    6 入札

    Description: We are seeking a proficient Wix developer with a keen eye for design to collaborate on an immediate project. The primary tasks involve ensuring the responsiveness of the website across all devices, creating an inner page layout for case studies, uploading content, and implementing minor design enhancements. Requirements: - Proficient in Wix development, including advanced knowledge of its features and capabilities. - Demonstrated ability to design visually appealing and user-friendly interfaces. - Experience in optimizing websites for responsiveness across various devices. - Ability to commence work immediately and deliver timely results. - Strong attention to detail and dedication to quality assurance. If you possess the requisite skills and are availab...

    $36 (Avg Bid)
    $36 平均入札額
    12 入札

    I'm in need of a CSS specialist who can meticulously recreate a graphic using CSS, ensuring the appearance and effects remain consistent across different devices and browsers. Expectations: - Recreate the graphic involving rings/circles, focusing on replicating the gradient color, glow/light shadows/neon effect, and depth. - The placement of rings/circles doesn't need to be identical to the reference image, but the overall look and effects must be maintained. Key Requirements: - Strong CSS skills with a proven track record in creating visually appealing and interactive designs. - Familiarity with various CSS effects, particularly gradient colors, glow, and depth. - Ability to ensure compatibility and responsiveness across different browsers and platforms. ...

    $60 (Avg Bid)
    保証

    Need a flutterflow developer who can work with in team and have experience in this, have knowledge of css and html, authentication and authorization, usages of swagger end points

    $246 (Avg Bid)
    $246 平均入札額
    10 入札

    I'm in need of a developer proficient in Python who can create a video tutorial. The tutorial should showcase the process of building a user authentication login page for a web application using the Microsoft Graph API. The loging should just allow pre-registered users (from azure dashboard) to enter the app. Ideally the should build a little login page using streamlit! Key Requirements: - Expertise in Python: Comprehensive proficiency in Python is a must, as the tutorial is centered around this language. - Familiarity with Microsoft Graph API: The ability to leverage the Microsoft Graph API for user authentication is essential. - Video Creation: While I'm not looking for a professional video maker, t...

    $90 (Avg Bid)
    $90 平均入札額
    11 入札

    I am in need of an Angular developer to tackle two core tasks in our ongoing project. I seek expert help in front-end development and UI/UX design. We have a design concept and a wireframe to work with. This is not a basic project; the UI/UX design can be termed as intermediate, it has complex features. Your responsibilities will include: - Implementing this intermediate UI/UX design in a responsive, user-friendly manner - Conducting front-end development Ideal Skills: - Proven Angular development experience - Substantial knowledge in front-end technologies like HTML, CSS and JavaScript - Proficiency in UI/UX software such as Adobe Suite, Sketch, etc. - Experience working with wireframes and design concepts - Ability to deal with and implemen...

    $374 (Avg Bid)
    $374 平均入札額
    20 入札

    I'm in need of a skilled .Net developer with a strong background in C# programming. The project at hand involves the creation of a web application, specifically a content management system (CMS). Key requirements: - Proficiency in C# programming is essential - Strong grasp of the .Net framework - Experience in developing web applications using ASP.Net MVC - Prior experience with CMS development is highly preferred Your primary responsibility will be to develop a robust, efficient, and user-friendly CMS. This involves creating a system that allows for easy management and modification of digital content. If you have a proven track record in C# development, particularly within the context of web applications and ...

    $15 / hr (Avg Bid)
    $15 / hr 平均入札額
    106 入札

    I need a Flutter developer to work on an exciting project, should speak Arabic. The app sells and buys things, it is an e-commerce app multi-vender. please attached your work links

    $495 (Avg Bid)
    $495 平均入札額
    94 入札

    I'm seeking a talented React JS developer to help fix some UI and functionality issues in my project. The bugs are more on the intermediate level, involving the malfunctioning of certain features. Key Tasks: - Identify and diagnose the existing issues in the UI - Fix the functionality problems that are impairing the user experience The ideal candidate must have: - Proven experience in React JS development - Strong problem-solving skills - A proactive attitude in identifying and resolving bugs - Previous experience in debugging intermediate level issues Please include your experience in your application, and ideally, some examples of past work where you've dealt with similar bugs.

    $4 / hr (Avg Bid)
    $4 / hr 平均入札額
    44 入札

    ...Front-end: React or Angular for building a dynamic web application. Back-end: Node.js with Express for server management and API integration. Database: MongoDB or PostgreSQL for storing session data securely. Authentication: OAuth for handling secure authentication with streaming services. Technical Requirements and Development 1. Secure Authentication: Implement OAuth or a similar secure authentication protocol to allow users to log into their streaming services without storing their credentials. 2. Device Management: Develop a system to manage devices that can stream content, ensuring only authorized users can access the services during their stay. 3. Session Management: Ensure that user sessions are automatically ended upon checkout, or provide a simple ...

    $723 (Avg Bid)
    $723 平均入札額
    49 入札

    I'm seeking a talented Android app developer to create a comprehensive educational platform. The app will focus on engaging the user in their learning process through interactive quizzes. Key Features: - Development for Android platform Ideal Skills and Experience: - Proficient in Android app development - Experience in building educational apps would be a plus - Familiarity with integrating interactive quizzes - Strong understanding of UI/UX for educational purposes Your role will be instrumental in shaping a platform that combines educational content with interactive assessments. This is an opportunity to make a significant impact in the field of mobile education.

    $220 (Avg Bid)
    $220 平均入札額
    44 入札

    I'm seeking a talented web developer to build an E-commerce platform dedicated to physical products. As the ideal candidate, your skills and expertise should cover: - Extensive e-commerce website development experience - Familiarity with creating websites oriented towards selling physical products - Proficiency in integrating Bank Transfers and PayPal payment methods onto websites Your prime responsibility will be crafting a reliable, user-friendly e-commerce website that can facilitate seamless transactions. Knowing how to make a site that's easy to navigate and appealing to potential customers is critical to your role. Your dedication and attention to detail will directly influence the success of our virtual store. Let's create an e-com...

    $550 (Avg Bid)
    $550 平均入札額
    244 入札
    Trophy icon Tron Smart Contract Developer 4 日 left

    We are looking for a skilled Tron developer to join our team and help develop a smart contract for a wallet application. The ideal candidate should have experience with Tron blockchain development and be familiar with BIP 39 or BIP 44 for address generation. Responsibilities: 1) Develop a smart contract on the Tron blockchain for a wallet application. 2) Implement functionality for address generation using BIP 39 or BIP 44. 3) Ensure that fees for all wallet transactions, including sending TRX or any ERC10 or ERC20 tokens, are deducted from a specified multiple accounts assigned in the smart contract, and not from user. 4) Also user need to pay the fees to the contract as an escrow, i.e. user will not pay the transaction fee, the transact...

    $1000 (Avg Bid)
    保証
    $1000
    2 エントリー

    We have built a customized website in core php and need another experienced developer to join the team to fix some bugs, We are looking for a very experienced php developer for our project, you must have at least 12-15 years of experience with a good reference . Must have experience in multi-user programming, must know how to do quality coding, fix sql injections Conditions: You must be a independent freelancer. and share with some of your customized applications that u have worked on.

    $7 / hr (Avg Bid)
    $7 / hr 平均入札額
    83 入札

    In need of a proficient Lightspeed Ecom specialist to assist with theme customization and product import and setup. This is a long-term project with no strict deadline, so I'm looking for someone who can offer dedicated, ongoing support. Key Responsibilities: - Customize the theme of my Lightspeed Ecom store to align with my brand and optimize user experience. - Import and set up products on the platform, ensuring they are accurately categorized, tagged, and presented well. Ideal Experience & Skills: - Strong background in working with Lightspeed Ecom, including previous theme customization projects. - Proven expertise in product import and setup, particularly in an ecommerce context. - Ability to understand and reflect my brand in the design of the store. -...

    $14 / hr (Avg Bid)
    $14 / hr 平均入札額
    98 入札

    Laravel and Flutter dev Developer needed, only who know both of them.

    $96 (Avg Bid)
    $96 平均入札額
    30 入札

    I'm in need of a full-stack developer to create a custom-built site for me. The specific skill set I'm looking for includes: - Expertise in both front-end and back-end development - Proven experience with PHP, JavaScript, HTML5, CSS3,reaact Nextjs React Native - Ability to manage server side languages, web application architecture, data storage solutions I haven't detailed the key functionalities and features for my site yet, but I expect the chosen participant to be proficient in implementing diverse web functions when necessary. Prior experience in similar projects will be highly considered. Looking forward to your bids!

    $538 (Avg Bid)
    $538 平均入札額
    150 入札

    I urgently need a CodeIgniter expert with 2-3 years of experience to help me complete a project in 7 days. The project involves developing a new feature for my existing website. More specifically, I require the integration of search and filter options. These additions are crucial for the website's user interface and overall functionality. Key responsibilities include: - Understanding current website structure and design - Implementing search and filter options - Ensuring seamless performance and user experience Ideal candidate should possess: - 2-3 years of hands-on experience with CodeIgniter - Strong proficiency in front-end technologies like HTML, CSS, and JavaScript - Proven track record of developing and integrating new website features - Ability to work ...

    $18 - $150
    シール NDA
    $18 - $150
    7 入札

    Make the website same as the existing website, studio.d-id.com. The Backend will be provided. Please share your thoughts on how you would approach this project and what experience you bring to the table.

    $13 / hr (Avg Bid)
    $13 / hr 平均入札額
    130 入札

    ...experienced professional to assist me in creating a Drupal website, developing Moodle courses, and integrating the two platforms seamlessly. Key Project Details: - Drupal Website Development: I'm looking for someone who has extensive experience in Drupal to create a professional, user-friendly, and responsive informational website. - Moodle Course Creation: The ideal candidate will be able to develop engaging and interactive Moodle courses consisting of text-based lessons, video tutorials, and interactive quizzes. The courses should be structured in a way that is both informative and engaging for learners. - Drupal and Moodle Integration: I'm looking for someone who has experience in integrating Drupal websites w...

    $17 / hr (Avg Bid)
    $17 / hr 平均入札額
    57 入札

    I'm seeking an experienced WordPress developer to craft an e-commerce website primarily using Easy Digital Downloads. Here's what I'm looking for: - Create an intuitive and seamless e-commerce experience. - Integrate Easy Digital Downloads as the core marketplace plugin. - Set up multiple Indian payment gateways, such as Net Banking, BHIM, GPay, and Phone Pay, ensuring security and ease of use. - Optimize site for performance, scalability, and SEO. Ideal Skills: - Proficiency in WordPress & Easy Digital Downloads - Experience with payment gateway integration - Strong portfolio with e-commerce examples - SEO and performance optimization expertise The successful freelancer will demonstrate a strong understanding of e-commerce strategies, particularl...

    $110 (Avg Bid)
    $110 平均入札額
    57 入札

    Hi Marc Developer, I noticed your profile and would like to offer you my project. We can discuss any details over chat.

    $66 (Avg Bid)
    $66 平均入札額
    1 入札

    Hi Marc Developer, I noticed your profile and would like to offer you my project. We can discuss any details over chat.

    $69 (Avg Bid)
    $69 平均入札額
    1 入札

    It is necessary solve two bugs to a Laravel application regard the frontend of condition use php 7.4. if it is necessary you must do changes to the database and the backend

    $27 (Avg Bid)
    $27 平均入札額
    61 入札

    I'm looking for a professional who can assist with securing approval for our Facebook Developer app. The app in question involves social media integration to the stackpost & ChatPion apps. Key tasks include: - Guiding through the approval process - Ensuring the app meets Facebook's requirements - Resolving any issues that may arise The project requires someone with a deep understanding of Facebook's policies and API requirements. Prior experience in securing approvals for similar apps is a significant advantage. Key skills and experience: - Proficient in Facebook Developer guidelines - Experience in securing app approvals - Familiarity with social media integration - Excellent problem-solving skills

    $12 (Avg Bid)
    $12 平均入札額
    1 入札

    I have a desktop application made using Electron software for electrochemistry experiments and I'm looking for a skilled front-end developer to help with software packaging and COM port detection. Ideal Skills and Experience: - Expertise in Front-End Development, specifically with Javascript and HTML - Experience with Electron software - Prior experience with arduino and python, a bonus - Strong understanding of software packaging in Electron applications The application should be compatible with Windows operating system. I need help fixing certain issues like the selecting the COM Port, the functionality needs to be re-written so that it is performed by Electron's WebAPI rather than Python(current). The start-up image must be the company ...

    $84 (Avg Bid)
    $84 平均入札額
    28 入札

    I'm in need of a skilled PHP developer to create a custom admin dashboard. The primary goal of this project is to provide a user-friendly interface for my data, with the following features in mind: - **Data Visualization**: I want the dashboard to be able to display key data pertinent to my business. This may include sales data, user activity, and website traffic. - **User Management**: While not explicitly stated, I understand the importance of user management in an admin dashboard. Therefore, building a system that allows for user management is a crucial part of this project. - **Role-based Access Control**: I want the dashboard to have role-based access control. This means that users will have different levels of access based...

    $16 / hr (Avg Bid)
    $16 / hr 平均入札額
    116 入札

    I'm seeking an experienced Flutter developer to assist in the creation of an Android application. Key Points: - The main purpose of the app is not yet defined. We are open to ideas and suggestions. - We don't have a specific design in mind, so I'll need the developer to lead the design process. - The primary platform for this app is Android. Requirements: - Proficiency in Flutter and Dart - Experience in designing mobile applications - Strong problem-solving skills and creativity - Ability to work independently and think critically

    $61 / hr (Avg Bid)
    $61 / hr 平均入札額
    79 入札
    android app developer 6 日 left
    認証完了

    Hello am looking for someone to deploy my dating app in playstore i have a source code and i need someone to make the apk file change the app names fix few things and upload it to playstore, i need immediately

    $39 / hr (Avg Bid)
    $39 / hr 平均入札額
    76 入札

    I'm in need of an experienced PHP backend developer who can assist me with urgent server configuration and API integration tasks. Specifically, I would require the following: - Server Configuration: I need someone who is well-versed in server setup and configuration, ensuring a smooth and efficient back-end infrastructure. The ideal candidate should be able to ensure optimal performance and security. - API Integration: There is a need for the integration of an 'informative application' API. This task requires someone with prior experience in integrating custom APIs and a strong understanding of how to effectively connect APIs for seamless functionality. Ideal Skills and Experience: - Proficient in PHP for backend development. - St...

    $80 (Avg Bid)
    $80 平均入札額
    26 入札

    I'm in need of a developer proficient in Python who can create a video tutorial. The tutorial should showcase the process of building a user authentication login page for a web application using the Microsoft Graph API. The loging should just allow pre-registered users (from azure dashboard) to enter the app. Ideally the should build a little login page using streamlit! Key Requirements: - Expertise in Python: Comprehensive proficiency in Python is a must, as the tutorial is centered around this language. - Familiarity with Microsoft Graph API: The ability to leverage the Microsoft Graph API for user authentication is essential. - Video Creation: While I'm not looking for a professional video maker, t...

    $25 (Avg Bid)
    $25 平均入札額
    11 入札

    Hiring a skilled WordPress Developer for ongoing agency client work. IMPORTANT: - Must be available to work 8 hours per day during US Central Time (Monday to Friday) - All work must be performed on a Windows Remote Desktop which comes with fast internet, strong processor and license to all required tools like Photoshop, code editor etc. The developer will be responsible for daily tasks that include updating web pages, integrating new features into existing WordPress sites, and handling some graphic-related tasks, such as designing and setting up email newsletter templates. Requirements : - Proficiency in WordPress, including themes and plugins - Experience with HTML, CSS, JavaScript, and PHP - Ability to work with graphic design tools such as Adobe Photoshop...

    $19 / hr (Avg Bid)
    $19 / hr 平均入札額
    310 入札
    Flutter Socket Developer Needed 6 日 left
    認証完了

    I am looking for a Flutter developer with experience in working with sockets to help me for application. Ideal Skills and Experience: - Proven experience in developing Flutter applications - Extensive experience with socket programming - Previous work on real-time chat applications preferred Please note, I am only looking for individual developers, no companies.

    $27 (Avg Bid)
    $27 平均入札額
    14 入札

    We're looking for a seasoned backend developer adept at working with the platform. Our project primarily involves rectifying some issues and implementing standout features. The scope of work includes: - Implementing a seamless payment processing system. - Addressing some undisclosed issues. - Incorporating a solid user authentication system. - Optimizing the platform's performance. Prospective freelancers should possess proven experience in backend development, with solid understanding of different programming languages. Practical exposure to database management or mobile app development would be a plus, but is not a mandatory requirement. Prior experience with platform is a necessity. A prompt turnaround ...

    $128 (Avg Bid)
    $128 平均入札額
    32 入札

    I'm looking for an experienced Excel Power-BI professional to assist me with various tasks. Key requirements: - Proficiency in Excel Power-BI. - Demonstrated experience in data analysis, dashboard creation, and report generation. - Ability to work with minimal supervision. I will share more details in via chat box. Only interested person placed a bid Thanks

    $13 (Avg Bid)
    $13 平均入札額
    11 入札

    I'm seeking a Django and Python Fullstack developer who can lend their expertise to my application project. The chosen freelancer should excel in creating: - Robust user authentication and authorization systems - Seamless database integration - Responsive design that adapt to various devices I have certain design ideas but I would highly appreciate guidance to help realize these concepts. The freelancer should possess a strong grasp of user-centric design and prove instrumental in translating these concepts into a streamlined, functional, and easy-to-use interface. Ideal skills: Python, Django, Database Management, User Interface Design, User Experience Design, and Responsive Web Design. It's a bonus if the candidate has a knack for m...

    $579 (Avg Bid)
    $579 平均入札額
    70 入札

    I require a skilled MERN developer who can also work with Flutter, for a month-long project focusing on developing a mobile application. Key Deliverables: - Develop a mobile application using Flutter - Ensure the application is compatible with both iOS and Android platforms Ideal Skills: - Proficiency in MERN stack - Strong experience in Flutter - Previous experience in mobile application development - Ability to work with both iOS and Android platforms The project is time-sensitive, so promptness in delivering quality work is a must.

    $445 (Avg Bid)
    $445 平均入札額
    51 入札

    I'm in need of an experienced web developer to create an e-commerce website for me. The site will need to cater to customers' needs and provide a seamless shopping experience. Key Skills: - Proficiency in e-commerce web development - Ability to integrate payment methods securely - Strong understanding of UI/UX principles - Time management skills to deliver within a month

    $141 (Avg Bid)
    $141 平均入札額
    65 入札
    Created a Website with 3D Logo 6 日 left
    認証完了

    Experienced Web Developer for IT Managed Services Company Website Company: Tymor Technologies Description: Tymor Technologies, a leading IT managed services provider, is seeking a highly skilled and experienced web developer to design and develop a professional website that reflects our brand and services. The website should closely resemble the style and functionality of Ntiva, featuring a 3D logo and animations. The website will include over 25 pages of content, each with unique images and content relevant to the IT managed services industry. Key Requirements: Proven Experience: Demonstrated experience in web development, with a portfolio showcasing similar projects. Design Expertise: Ability to create a website with ...

    $307 (Avg Bid)
    $307 平均入札額
    42 入札

    As an innovative company in need of a Jr. Flutter Developer with 1-2 years of experience, we are seeking a capable individual to join our team on a monthly basis. The successful candidate will work on mobile application projects. Key Responsibilities: - Development of mobile applications utilizing Flutter - Incorporation of high-quality UI/UX Design and seamless User Experience - Efficient integration of third-party APIs - Proper State Management to ensure the application runs smoothly Extra: - Previous experience with Audio Video Call projects will be a plus The ideal candidate must have: - 1-2 years of experience in Flutter development - Strong understanding of UI/UX design principles - Proven experience in API integration - Solid grasp of state man...

    $372 (Avg Bid)
    $372 平均入札額
    64 入札

    I need an experienced Wordpress developer to create a custom online form on my website using WPForms. The form should save all submitted data to a database. Here are the specifics: - **Export Data:** The form's data should be exported in Excel format. - **Client Communication:** The data collected needs to be sent to the client as a PDF document. - **Form Fields:** The form should include fields for 'Contact Information', 'Service Request Details' and 'User Feedback'. This project also includes the task of taking a form I already have in PDF format, and converting it to a WPForms. Please note that this form is quite complex, so experience with custom fields and complex form layouts is desired. I...

    $35 (Avg Bid)
    $35 平均入札額
    96 入札

    Hello, I'm in need of a skilled UI developer with solid PHP experience to assist with a project. Strong UI Experience + PHP Experience - Have to fix few pages design & layout change for 1 page. Its 4 - 5 hrs work for experience , i will share FTP detail & task detail document in DM Max Budget 1000 INR Regard

    $12 (Avg Bid)
    $12 平均入札額
    12 入札

    I'm currently on the search for a skillful web developer - preferably one with a proven track record in crafting effective e-commerce sites. It's crucial that your portfolio showcases expertise in creating sites that not only feature a blogging platform but also effectively integrates social media functionalities. Your background should include: - Developing engaging e-commerce websites to showcase tangible products - Creating intuitive UIs that make product discovery and purchase simple - Incorporating a blogging platform into a business website - Implementing social media functionalities into a website The primary aim here is to architect a website for my business that serves as an attracting platform for visito...

    $308 (Avg Bid)
    $308 平均入札額
    95 入札

    I'm searching for a proficient mail developer who can accomplish the following tasks: - Write engaging email copy. - Create a Zimbra mailer using either SOAP API or EWS. You must have experience with all mentioned platforms, namely Zimbra, SOAP API, and EWS (Exchange Web Services). The developed Zimbra mailer needs to have the functionality to send emails. Kindly bid if you have the necessary skills and experience. Look forward to working with professionals in this area.

    $576 (Avg Bid)
    $576 平均入札額
    27 入札

    I'm looking for a skilled PHP Laravel developer to work on a project basis. The ideal candidate should have expertise in the following areas: - Frontend Development - Backend Development - Database Management

    $4 / hr (Avg Bid)
    $4 / hr 平均入札額
    55 入札

    I'm looking for an experienced Python developer who has previously worked with options Greeks and the Zerodha API. Your main tasks will involve: - add third order greeks to an existing code The ideal candidate should have a strong command over Python, especially the Pandas library, and a thorough understanding of financial markets, particularly options Greeks. Prior experience working with the Zerodha API will be highly beneficial for this role. I look forward to your proposals!

    $15 (Avg Bid)
    $15 平均入札額
    5 入札

    We are seeking an experienced Shopify developer to create a custom tracking system for our Shopify store. This system will manage and update the status of our workflow and must be capable of sending notifications via email or text. Additionally, we are looking to integrate this system with Klaviyo for enhanced notification capabilities. Key Features Needed: Status Tracking: Ability to update and track the following statuses: Checked in in Queue Work In-Progress Waiting on Customer Waiting for Parts Complete Ready for Pick-up Notifications: Send automated notifications via email or text. Potential integration with Klaviyo for advanced notification options. Requirements: Proven experience in developing Shopify applications or integrations. Strong understanding of Shopify&#...

    $44 (Avg Bid)
    $44 平均入札額
    19 入札