Download  http://pecl.php.net/package/scrypt

GitHub repo  https://github.com/DomBlack/php-scrypt

Install PECL

pecl install scrypt

Use Linux command lines to install

Note: Change  /usr/bin/  to the path where your own PHP bin file is located.

wget http://pecl.php.net/get/scrypt-1.4.2.tgz
tar xf scrypt-1.4.2.tgz
cd scrypt
/usr/bin/phpsize
./configure --enable-scrypt --with-php-config=/usr/bin/php-config
make && make install

Add configurations in php.ini file.

;Enable scrypt extension module
extension=scrypt.so