Introduction

Signal is a popular encrypted messaging application that has gained significant attention. The project is open source, making it possible for developers to build and run their own instances. This guide covers the process of compiling and running the latest Signal Android client.

Obtaining the Source Code

Start by cloning the official Signal Android repository from GitHub:

git clone https://github.com/signalapp/Signal-Android.git
cd Signal-Android

After cloning, check the available tags to find version 7.40.0:

git tag | grep "v7.40"
git checkout tags/v7.40.0 -b working-branch

Verify the checkout was successful:

git log -1 --oneline

Project Setup in Android Studio

Open the project in Android Studio (version 2024.3.1 or later recommended). The build system will automatically begin downloading dependencies. Ensure your network connection is stable during this phase.

If you encounter network errors such as timeout issues or SSL handshake failures, retry the synchronization. For building version 7.39.3 and later, Android SDK Platform 35 is required. Install it before proceeding if not already available.

Running the Application

Once dependency synchronization completes successfully, connect a device with USB debugging enabled. Select your device from the target dropdown and click the run button to deploy the application.

The application should launch directly on the connected device.

Server-Side Considerations

Signal has also open-sourced its server implementation, which is available in a separate repository. This raises an interesting question: can developers host their own Signal server for private or organizational use?

Self-hosted deployments are indeed possible and allow complete control over the messaging infrastructure while maintaining end-to-end encryption for all communications.