make sure you have at least redis v4.0+
redis-server --version
redis-cli --version
install the build-essential package
apt-get install build-essential
git clone https://github.com/RedisLabsModules/rejson.git
cd rejson/
make
cd src/
mkdir /etc/redis/modules/
mv rejson.so /etc/redis/modules/
add this line to /etc/redis/redis.conf
loadmodule /etc/redis/modules/rejson.so
restart redis server
service redis-server restart
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