Pros:
MySQL natively support (With cymysql)
Completed Open Source Project, no further development needed

Cons:
No longer maintained, potential safety issue
Not compatible with some mainstream cipher (AES-GCM)

Due to the lack of dependencies and the removal of the M2Crypto library from YUM, the experience of installing Shadowsocks-manyuser on CentOS 8 will not be enjoyable without a reference guide.

WARNING: Shadowsocks-manyuser is incompatible with Python3 standard, thus, the safeness guarantee will be gone in 2 months.

WARNING: Shadowsocks-manyuser is officially deprecated. You shouldn’t follow this tutorial.

Install Dependencies

yum install

wget python27 gcc swig openssl-devel redhat-rpm-config python2-devel tar make git

To note that on CentOS 8, install by yum with one calling may not work as expected. Please double check to make sure you have everything listed installed.

Install pip and something should be installed by pip

wget https://bootstrap.pypa.io/get-pip.py
python2 get-pip.py
pip install pyparsing
pip install cymysql
pip install m2crypto

Optional: Install libsodium (To support CHACHA20 encryption)

# Download, Unzip, Compile and Install
wget -N --no-check-certificate https://download.libsodium.org/libsodium/releases/LATEST.tar.gz 
tar zvxf LATEST.tar.gz 
cd libsodium-* 
./configure 
make && make install
# Add link to system library
echo "/usr/local/lib" >> /etc/ld.so.conf
ldconfig 
# Expect no output info. Otherwise something went wrong

Installation and configuration of Shadowsocks-manyuser

Thanks to Clowwindy, Mengskysama and all the other developers for making this project possible.

git clone -b manyuser https://github.com/mengskysama/shadowsocks-rm.git
cd shadowsocks-rm/shadowsocks/ # Enter the directory
vi config.py # Edit configuration file

Run Shadowsocks-manyuser

python2 servers.py # In the directory, call by hand. 
/usr/bin/python2 {DIRECTORY}/shadowsocks-rm/shadowsocks/servers.py # Full path might be needed

By the way, I am very glad and surprised to see the CentOS community is keeping making solid progress, despite being slow and late. I feel supported when I see the operating system I choose to use is being maintained well.