For compiling this extension Boost, OpenSSL, and Protobuf libraries are required as dependencies.
An example installation on Ubuntu 16.04:
$ apt install build-essential libprotobuf-dev libboost-dev openssl protobuf-compiler $ add-apt-repository ppa:ondrej/php $ apt install php7.1-cli php7.1-dev php7.1-mysql php7.1-pdo php7.1-xml $ pecl install mysql_xdevapi
This extension requires a MySQL 8+ server with the X plugin enabled (default).