Creating a Step-by-Step Guide on How to Build Your Own WhatsApp from Scratch

How to build whatsapp

If you’re looking to create your own messaging app like WhatsApp, there are a few things you need to know. WhatsApp is not just a simple chat application; it also provides voice calling, video calling, group chat, file sharing, and many more features. In order to build a similar app, you need to understand the technology and architecture behind it.

One of the first things you need to do is choose a backend for your app. There are several options available, but one of the most popular choices is MBaaS (Mobile Backend as a Service). MBaaS provides a cloud-based backend infrastructure, which makes it easy to integrate various features like real-time messaging, push notifications, and user authentication. You can choose from providers like Firebase, Parse, or Apphitect.

Next, you need to decide on the programming languages and frameworks to use. WhatsApp is built using a combination of XMPP (Extensible Messaging and Presence Protocol), MySQL for database management, and various open-source libraries. You can find the source code and documentation for these technologies to study and follow.

After setting up your backend and choosing the right tools, you need to focus on the core features of your app. In order to create a WhatsApp-like experience, you need to implement features like chat synchronization, group chats, message encryption, voice and video calling, and chatbots for automated customer support. It’s also important to ensure the security and privacy of your users’ data, as well as prevent the spread of fake news or false information.

If you’re a business looking to build a messaging app like WhatsApp, it’s essential to provide excellent customer support. You can integrate features like in-app support chat, FAQs, and user forums to assist your customers. Additionally, you can use third-party SDKs like Contus Fly or Mesibo to add voice and video calling capabilities to your app.

In conclusion, building a WhatsApp-like app requires a combination of technical expertise, careful planning, and attention to detail. By following the steps and tips outlined in this article, you can create a powerful communication application that meets the needs of businesses and individuals alike.

How to Build a Chat Application Like WhatsApp

Building a chat application like WhatsApp requires a careful and systematic approach to ensure the accuracy, reliability, and security of the messaging platform. WhatsApp, known for its real-time messaging capabilities, encrypted communication, and user-friendly features, has become one of the most popular messaging applications worldwide.

Here are the steps to build a chat application similar to WhatsApp:

1. Define the Project Scope:

Clearly define the goals, target audience, and features of your chat application. Determine whether you want to build a standalone chat application or integrate it with other platforms and services.

2. Choose the Right Technologies:

Study the different technologies available for building a chat application. Consider using backend technologies like Ejabberd for real-time chat synchronization or third-party SDKs for easy integration. Ensure the technologies you choose align with your project requirements.

3. Ensure Security and Compliance:

Security and privacy are crucial for a messaging application. Implement end-to-end encryption to protect user messages and ensure compliance with relevant privacy regulations. Regularly update your application to prevent security breaches and unauthorized access.

4. Handle Large User Base and Group Chats:

WhatsApp’s popularity stems from its ability to handle enormous user bases and group chats. Design your database schema, backend, and infrastructure to handle rapid growth and ensure smooth performance for your users.

5. Implement User-Friendly Features:

Pay attention to the features that make WhatsApp popular, such as easy media sharing (photos, videos), voice, and video calling. Consider adding additional features like chatbots to improve user engagement and experience.

6. Design an Intuitive User Interface:

Create a user interface that is easy to navigate and visually appealing. Include features like notifications and message read/unread status to enhance user experience and keep them engaged.

7. Optimize for Multiple Platforms:

Ensure your chat application is available on various platforms like iOS, Android, Windows, and the web. Develop platform-specific applications or use frameworks for cross-platform development to reach a wider audience.

8. Test, Test, Test:

Thoroughly test your chat application for usability, functionality, and security. Identify and fix any bugs or performance issues before making your application available to your customers.

9. Deploy on the Cloud:

Consider using cloud infrastructure to deploy your chat application. Cloud-based solutions like MBaaS (Mobile Backend as a Service) can provide scalability, easy setup, and maintenance for your application.

10. Growth and Customer Support:

Continuously monitor user feedback and complaints to enhance the application’s performance and address any issues. Provide excellent customer support to build trust and retain your customer base.

In conclusion, building a chat application like WhatsApp may seem challenging, but by following these steps and utilizing the right technologies, you can create a secure and user-friendly messaging app that rivals WhatsApp’s success.

Should you create a WhatsApp-like project for your business

If you are considering creating a WhatsApp-like project for your business, there are several factors that you should take into account before making a decision. While developing a chat application similar to WhatsApp may seem like an attractive idea, it is essential to assess whether it aligns with your business goals and requirements.

One of the critical aspects to consider is whether your business needs to have real-time messaging capability. If instant communication is crucial for your daily operations or if you want to offer enhanced customer service through direct messaging, developing a WhatsApp-like app might be a suitable solution. Instant messaging apps enable you to promptly send and receive messages, share media files, and engage in voice and video calls, thereby fostering effective communication.

You should also evaluate the available APIs and SDKs that can facilitate the development of a WhatsApp-like app. There are various options such as Mesibo, CometChat, SendBird, and Chat SDK, among others, which offer backend services for messaging synchronization, offline message support, and group chats. When choosing an API or SDK, consider factors such as ease of integration, documentation quality, and compliance with your business requirements.

Furthermore, you must examine the cost implications associated with developing a WhatsApp-like project. Some APIs and SDKs offer free plans with limited features, while others require a monthly subscription or have a paid pricing structure. Assess your budget and growth projections to choose a solution that aligns with your financial capabilities and future scalability needs.

If you decide to proceed with building a WhatsApp-like project, you will need to hire an expert team with the necessary technical skills and experience in developing real-time messaging apps. These professionals can guide you through the steps of app development and assist you in choosing the right technology stack, such as XMPP or Ejabberd, to ensure a solid foundation for your project.

Another key consideration is the potential for chatbot integration. WhatsApp-like apps can benefit from chatbots that automate customer inquiries and provide instant responses. If you envision incorporating chatbot capabilities into your app, ensure that the chosen API or SDK supports chatbot integration.

In conclusion, creating a WhatsApp-like project for your business can offer several advantages, including improved communication, enhanced customer service, and efficient messaging. However, it is crucial to thoroughly evaluate your business needs, available resources, and technical requirements before committing to such a project. With the right approach and expert guidance, building a WhatsApp-like app can be a valuable addition to your business.

How to build a messaging app using SDKs

If you are an expert developer looking to build a messaging app, using SDKs (Software Development Kits) can simplify the process. SDKs provide pre-built libraries and tools that enable developers to add messaging functionality to their applications more easily. This article will guide you through the necessary steps to create a messaging app using popular SDKs.

  1. Choose the right SDK: There are various options available, such as ChatSDK, SendBird, Contus, CometChat, and more. Research and choose an SDK that best suits your requirements.
  2. Read the documentation: After selecting an SDK, read their documentation thoroughly. This will help you understand the SDK’s features, functionalities, and how to integrate it into your app.
  3. Follow the code examples: Most SDKs provide sample code that demonstrates the implementation process. Follow these examples to understand how to use the SDK effectively.
  4. Build the chat interface: Use the SDK’s provided components to create chat-related functionalities like real-time messaging, group chats, voice and video calls, and chatbots.
  5. Implement security measures: Ensure that your app follows security standards and protocols to protect user data. Implement authentication mechanisms and encryption techniques to enhance privacy and prevent unauthorized access.
  6. Implement notifications: Users should receive notifications for new messages, group invitations, and other relevant activities. Integrate push notification services like Firebase Cloud Messaging or Apple Push Notification Service to send real-time alerts to users.
  7. Sync data across devices: Implement data synchronization mechanisms to ensure messages, chats, and other app data are consistent across devices. Use technologies like MySQL or MBaaS (Mobile Backend as a Service) to achieve this.
  8. Enhance user experience: Add features like media/file sharing, emojis, reactions, user profiles, and read receipts to make the app more engaging and user-friendly.
  9. Ensure compliance with regulations: If you’re building a messaging app for businesses or paid services, ensure compliance with applicable regulations, such as GDPR, CCPA, and data protection laws. Provide clear terms of service and privacy policy to protect user data and maintain transparency.
  10. Test and debug: Perform rigorous testing to identify and fix any bugs or issues. Test the app on different platforms and devices to ensure compatibility.
  11. Deploy the app: Once testing is complete, deploy the app on the desired platforms, such as iOS, Android, or web. Publish the app on respective app stores, like the Apple App Store or Google Play Store.
  12. Monitor and analyze: After launching the app, monitor its performance, user interactions, and growth metrics. Utilize analytics tools to gain insights into user behavior and identify areas for improvement.

By following these steps and utilizing the features provided by SDKs, you can build an excellent messaging app. However, keep in mind that building a successful messaging app takes time, dedication, and continuous improvements. Study the best practices, follow expert advice, and hire professionals if necessary to ensure your app’s success.

Contus Fly

Contus Fly is a prominent chat SDK that businesses can use to build their own WhatsApp-like messaging application. It offers excellent features such as chatbots, video and audio calls, file sharing, push notifications, and synchronization across devices. The Contus Fly documentation provides developers with all the necessary information and APIs to easily integrate the chat functionality into their applications.

Contus Fly uses the popular XMPP (Extensible Messaging and Presence Protocol) and Ejabberd for communication and presence. It also offers SDKs for iOS, Android, and web, making it easy for developers to build cross-platform chat applications. The Contus Fly SDKs have active developer communities and excellent support, ensuring developers can get the help they need while building their chat projects.

Contus Fly follows the paid monthly growth pricing model, which means businesses will pay based on their monthly active users. This can be an advantage for companies with fluctuating user bases, as they only pay for the users who are actively using the chat service.

In terms of data security and privacy, Contus Fly ensures the confidentiality and authenticity of the chats by using end-to-end encryption. This helps prevent any false or leaked messages during the chat sessions. Additionally, Contus Fly provides features like message forwarding and message deletion, allowing users to have control over their chat history.

If you’re looking to build a chat application like WhatsApp, Contus Fly is an excellent choice. The extensive documentation, active developer community, and reliable features make it a recommended option for businesses of all sizes.


SendBird is a popular chat API and messaging SDK that developers can use to build real-time communication features into their applications. It offers a wide range of functionalities including group chats, one-on-one messaging, push notifications, and file sharing.

With SendBird, businesses can create their own chat application with excellent security measures in place. The platform follows industry-standard encryption technologies to ensure the confidentiality and integrity of messages. SendBird also provides active support to its customers, with paid plans available for additional features and support.

SendBird’s backend is built on a cloud-based infrastructure, which provides excellent scalability and reliability. The company’s APIs are easy to integrate with various platforms and technologies such as iOS, Android, JavaScript, Unity, .NET, and React Native. Developers can quickly set up a chat feature in an app by following the step-by-step integration guide provided on SendBird’s webpage.

One of the prominent features of SendBird is its ability to create chatbots. Developers can use this function to automate certain tasks and enhance the user experience. Chatbots can perform a variety of actions, such as sending automated replies, providing in-app support, and delivering personalized content.

SendBird also offers video chat capabilities through its SendBird Calls product. This allows businesses to easily integrate video calling into their applications, providing a more interactive communication experience for users.

SendBird is an excellent choice for businesses looking to build their own messaging app or add real-time communication features to their existing applications. It provides a reliable and secure infrastructure along with a wide range of functionalities to support different use cases.

Integration Steps

To integrate SendBird into your application, follow these steps:

  1. Sign up for a SendBird account on their website.
  2. Create a new application.
  3. Retrieve your unique API keys provided by SendBird.
  4. Install the SendBird SDK into your application project.
  5. Initialize the SendBird SDK using your API keys.
  6. Implement the necessary code to handle chat functionalities, such as sending messages, creating group chats, and managing users.
  7. Test the chat functionalities in your application to ensure everything is working correctly.
  8. Deploy your application to make it live for users to utilize the chat features.

Other Messaging APIs and Technologies

Aside from SendBird, there are several other messaging APIs and technologies that developers can consider for building chat applications:

API/Technology Description
CometChat A messaging API that offers integration with popular platforms and technologies such as iOS, Android, React Native, and JavaScript.
Mesibo An open-source messaging platform that provides real-time chat API and backend infrastructure.
Ejabberd An XMPP-based messaging server that developers can use to build their own chat applications.
Apphitect An API and SDK provider that offers chat and messaging solutions for businesses.
Mesibo An open-source messaging platform that provides real-time chat API and backend infrastructure.
MySQL A popular open-source database management system that can be used to store chat data.

When choosing a messaging API or technology, it is important to consider factors such as ease of integration, scalability, security, and support. Each platform may offer different features and pricing structures, so it is recommended to research and compare multiple options before making a decision.


ChatSDK is a powerful open-source tool that allows you to easily build a chat application similar to WhatsApp. It provides a wide range of functions and features for real-time communication, such as sending messages, voice and video calls, group chats, push notifications, presence status, and more.

One of the key components of ChatSDK is the ejabberd XMPP server, which ensures reliable and secure message transmission. With ChatSDK, you can create your own messaging application or integrate it into your existing business webpage or application.

To build a chat application like WhatsApp using ChatSDK, you should follow these steps:

  1. Install and configure the ejabberd XMPP server.
  2. Integrate ChatSDK into your project by adding the required code snippets and libraries.
  3. Create a user interface for your chat application, including features like chat bubbles, user profiles, and chat history.
  4. Implement the necessary APIs for sending and receiving messages, managing contacts, and handling other functionalities.
  5. Ensure synchronization between devices and offer support for active chat sessions and presence notifications.
  6. Implement additional features like chatbots, file sharing, voice and video calls, and group chats as per your project requirements.
  7. Test the application thoroughly to ensure its functionality and security.
  8. Publish and market your chat application to attract users and grow your customer base.

ChatSDK also provides excellent documentation and support, which can be very helpful in building your chat application. You can find the complete source code and related resources on the official website of ChatSDK.

If you don’t have the expertise or time to build the chat application yourself, you can also hire an expert development team or companies like Contus, CometChat, or Mesibo, which offer paid services for building custom chat applications. These companies provide off-the-shelf solutions and customization options for your specific needs.

In conclusion, ChatSDK is a popular and excellent choice for building chat applications with real-time communication features. With its easy integration and extensive features, you can create a highly functional and secure chat application like WhatsApp. Follow the recommended steps and utilize the available resources to ensure the reliability, security, and ease of use of your application.



ApphiTect is a comprehensive suite of tools and libraries that developers can use to build WhatsApp-like applications. With ApphiTect, you can find the necessary SDKs and create the code needed to create a business-focused messaging application like WhatsApp.

One of the key features of ApphiTect is its excellent security and compliance with customer data protection and privacy. It uses advanced encryption techniques and security protocols to ensure the confidentiality and integrity of chats and other data.

In addition to security, ApphiTect also offers a range of useful functions for businesses, such as group chats, voice and video calls, presence check, message forwarding, and synchronization across multiple devices.

To build an application using ApphiTect, developers should follow a set of steps provided in the documentation. The documentation includes detailed guidelines on how to set up the development environment, integrate the required SDKs, and implement the desired features.

ApphiTect uses XMPP and ejabberd as the backend technology for real-time messaging. It also provides a push notification service to ensure that users receive instant updates even when they are not actively using the application.

One of the prominent features of ApphiTect is its easy integration with other applications and services. Developers can leverage this functionality to integrate ApphiTect with their existing business systems and workflows, leading to increased productivity and efficiency.

ApphiTect is developed by a company called Cometchat and is known for its expertise in building messaging applications. With years of experience, Cometchat has built a reputation for delivering high-quality software solutions that meet the needs of businesses of all sizes.

In conclusion, if you are looking to build a WhatsApp-like application, ApphiTect is an excellent choice. It provides all the necessary tools and resources to ensure the growth and success of your business. Whether you are a seasoned developer or just starting your journey, ApphiTect will guide you through the process and help you build a cutting-edge messaging application.

Hire expert developers for your next project

If you are planning to build your own messaging app like WhatsApp, it’s important to hire expert developers who have the necessary skills and experience in building such applications. Here, we will discuss the key aspects to consider when hiring developers for your project.

  1. Expertise in chat and communication technologies: The developers should have a deep understanding of the chat and communication technologies such as XMPP, which forms the backbone of messaging apps like WhatsApp. They should be familiar with the backend technologies like Ejabberd, as well as the documentation and APIs related to building chat applications.
  2. Experience in building messaging features: The developers should have prior experience in building messaging features like group chats, voice and video calls, and media sharing. They should also be able to integrate chatbots and other add-ons to enhance the functionality of the app.
  3. Focus on security and privacy: Messaging apps deal with sensitive user data, so it’s crucial to ensure the highest level of security and privacy for your users. The developers should have experience in implementing end-to-end encryption, compliance with data protection laws, and measures to prevent unauthorized access and data breaches.
  4. Knowledge of third-party integrations: A messaging app like WhatsApp often requires integration with third-party services like Amazon Web Services (AWS). The developers should be familiar with these integrations and be able to implement them seamlessly into your app.
  5. Ability to handle high user activity: WhatsApp is a popular messaging app with millions of active users. The developers you hire should have experience in developing scalable solutions that can handle high user activity and ensure a smooth user experience even during peak usage times.
  6. Check their portfolio and client testimonials: Before making a hiring decision, review the developers’ portfolio and check if they have previously built messaging apps or similar projects. Reading client testimonials will give you an idea of their expertise and reliability.
  7. Consider hiring from trusted sources: There are several reputable companies and freelancing platforms that offer expert developers. Some popular sources include Apphitect, Contus, and Chatsdk. Research and choose a source that best suits your requirements and budget.
  8. Offer competitive pay: To attract top-notch developers, you should be prepared to offer competitive compensation. Remember, hiring skilled professionals comes at a cost, but it will be worth it if you want to build a successful messaging app like WhatsApp.

In conclusion, building a messaging app like WhatsApp requires a team of expert developers who possess the right skills and experience. By following these tips and considering the factors mentioned above, you can hire the best developers for your next project and ensure its success.


CometChat is a prominent and excellent messaging platform that can be used to build a WhatsApp-like application. It offers various types of messaging, including text messages, voice calls, push notifications, and group chats. CometChat uses a backend-as-a-service (BaaS) approach, with MySQL as its database and cloud synchronization for real-time updates.

To create a WhatsApp-like app using CometChat, you will need to follow these steps:

  1. Create a CometChat account and set up your project.
  2. Integrate CometChat’s APIs into your application’s backend, using the provided documentation.
  3. Implement the necessary frontend components to handle chat messages and user presence.
  4. Ensure security and data compliance by following CometChat’s guidelines.
  5. Offer support for offline messaging and message synchronization.
  6. Implement features like voice calls, chatbots, and message forwarding to enhance the user experience.
  7. Check for growth and performance issues and optimize your app accordingly.

In addition to CometChat, there are other useful sources and tools available to build WhatsApp-like applications. Some popular options include Apphitect, Mesibo, and Mbaas. Depending on your specific requirements, hiring an expert developer or a development company might be a good option.

CometChat provides an excellent set of APIs and features that make it easy to build a WhatsApp-like application. It ensures the privacy and security of your customer data and offers seamless integration with your existing web or mobile application.

It’s important to note that building a WhatsApp-like app requires compliance with privacy regulations and data security policies. Ensure that you follow the necessary guidelines to protect user information and maintain data confidentiality.


Mesibo is a real-time messaging API and chat SDK that offers excellent communication features for businesses and developers. It can be used to build applications similar to WhatsApp, allowing users to send messages, make voice calls, share media files, and create group chats.

One of the prominent technologies Mesibo uses is XMPP (Extensible Messaging and Presence Protocol), which ensures the security and reliability of the messaging platform. Mesibo also offers chatbots, data synchronization, and compliance with GDPR (General Data Protection Regulation) for businesses to comply with privacy and security regulations.

Mesibo’s documentation provides developers with step-by-step instructions on how to build their own messaging app using Mesibo’s source code. The documentation also includes a list of useful resources and tips to prevent common pitfalls in messaging app development.

For businesses looking to build their own messaging app, Mesibo is a recommended choice due to its excellent features, security, and reliability. Mesibo follows the business model of a paid monthly subscription, which allows businesses to have access to all of Mesibo’s features and ongoing support.

Mesibo is an excellent choice for businesses that want to create their own customer support or communication app. By using Mesibo’s API and SDK, businesses can provide real-time messaging and support to their customers on various platforms such as webpages, Windows applications, and mobile apps.

Some popular messengers built with Mesibo include Contus Fly, Apphitect, and Ejabberd. These messengers have successfully implemented Mesibo’s real-time messaging features and have gained a significant user base.

In conclusion, Mesibo is a powerful and highly customizable messaging platform that businesses and developers can use to build their own real-time communication apps. With its excellent features and support, Mesibo is a reliable choice for businesses that require secure and efficient messaging services.

Security Tips and Useful Features

Security Tips and Useful Features

When building a messaging app like WhatsApp, it is essential to prioritize the security and privacy of your users. Here are some tips and features to consider:

  • End-to-End Encryption: Implement end-to-end encryption to ensure that only the intended recipients can access the messages.
  • Secure User Authentication: Use strong authentication methods like two-factor authentication to verify the identity of users.
  • Regular Security Audits: Conduct regular security audits to identify and fix any vulnerabilities in the app.
  • Privacy Settings: Provide users with privacy settings to control who can see their profile, status, and last seen details.
  • Message Encryption: Encrypt all messages sent through the app to prevent unauthorized access.
  • Backup Encryption: Encrypt user backups to protect their data in case of device loss or theft.
  • Social Engineering Awareness: Educate users about social engineering attacks and how to detect and prevent them.

In addition to security, here are some useful features to consider adding to your messaging app:

  • Audio and Video Calling: Offer voice and video calling functionalities to enhance communication.
  • Media Sharing: Allow users to share photos, videos, and other files with their contacts.
  • Push Notifications: Implement push notifications to keep users informed about new messages even when the app is not in use.
  • Offline Messaging: Enable users to send and receive messages even when they are offline, ensuring seamless communication.
  • Integration with Other Services: Provide integration with popular services like Google Drive or Dropbox for easy file sharing.
  • Real-time Chat Sync: Keep chats synchronized across devices to ensure users can seamlessly switch between platforms.
  • Prominent Documentation and Support: Create comprehensive documentation and offer excellent customer support to assist users with any issues or questions.

By following these tips and incorporating these features into your messaging app, you can ensure the reliability, security, and confidentiality of user communication. It will also contribute to the growth of your business by attracting more users and businesses that value secure and feature-rich messaging platforms.

To Sum Things Up

Building a messaging application like WhatsApp involves a series of steps and the use of various technologies. In this article, we delved into the process of creating a chat application from scratch.

First, we discussed the importance of choosing the right backend technologies such as Ejabberd, XMPP, or Amazon SNS to handle real-time messaging and push notifications. We also highlighted the need to ensure compliance with privacy and data security regulations.

Next, we explored the different types of chats that can be implemented, including one-on-one chats, group chats, and voice chats. We also recommended considering adding chatbots to enhance the communication experience.

We then discussed the various features and functionalities that a messaging application should offer, such as the ability to send messages, share media files, and support end-to-end encryption.

Furthermore, we mentioned some prominent companies in the industry that offer chat application development solutions, such as Contus, Sendbird, and ChatSDK. These companies can provide the necessary support and expertise to build a successful messaging application.

In terms of growth and monetization, we suggested exploring options like offering a freemium model with monthly paid subscriptions or incorporating advertisements into the application.

To conclude, building a messaging application like WhatsApp requires careful planning and a thorough understanding of the technologies and steps involved. By following the recommendations in this article and conducting further research, businesses can create an excellent messaging platform to support their customer communication needs.


When it comes to building a messaging app like WhatsApp, it’s important to rely on reliable sources for growth, data storage, and backend support. Here are some of the sources you can follow to build your own WhatsApp-like application:

  • WhatsApp API: WhatsApp offers an excellent API that developers can use to integrate messaging, voice, and video sharing features into their own application. It also provides documentation and support for developers to ensure smooth integration.
  • Ejabberd: Ejabberd is a popular XMPP server used for real-time chat applications. It offers excellent synchronization and message delivery features, making it a suitable backend choice for WhatsApp-like apps.
  • Chat SDKs: There are various chat SDKs available, such as Contus Fly, Apphitect, and SendBird. These SDKs provide easy integration for chat functionalities, allowing you to build a WhatsApp-like app quickly.
  • AWS (Amazon Web Services): AWS offers cloud services like EC2, S3, and RDS, which can be used to host your application and store data securely. It provides scalability and reliability, making it an ideal choice for a messaging app.
  • MySQL: If you prefer a traditional database system, MySQL can be used to store user data, chats, and other information. It is widely used and offers good performance.
  • Chatbot integration: Adding chatbot integration to your WhatsApp-like app can enhance the user experience. You can use platforms like Chatfuel and Chatteron to create and integrate chatbots.

These sources will provide you with the necessary tools and technologies to build a secure and feature-rich messaging app like WhatsApp. Remember to follow the compliance and security guidelines to ensure the privacy and security of your users’ data.


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