Compiling Stalwart JMAP from the source has the main advantage that binaries are built with optimizations specific to your hardware which may result in better performance. Another advantage is that you may enable or disable features to suit your needs.

To compile Stalwart JMAP you need the latest version of Rust as well as Clang version 10 or greater.

Install Rust

The fastest way to install rust is with rustup. On Unix systems run the following in your terminal, then follow the onscreen instructions

curl --proto '=https' --tlsv1.2 -sSf | sh

If you are running Windows 64-bit, download and run rustup‑init.exe, then follow the onscreen instructions.

Install Clang

If you are using Ubuntu Linux, you may install clang running:

sudo apt install clang

On MacOs execute:

brew install --with-toolchain llvm

Clone Repo

Clone the Stalwart JMAP repository:

git clone
cd jmap-server


Compile Stalwart JMAP by executing:

cargo build --release

Once the compilation process is completed, the Stalwart JMAP binary will be available under target/release/stalwart-jmap.