namecoin-install, updated 31.12.2023

install namecoin-core from https://www.namecoin.org/download/ | Namecoin Core Client (Stable Release)
install ncdns from https://www.namecoin.org/download/

add binaries to path. change "namecoin-nc22.0" and "ncdns-0.3-linux-x86_64-e41ca2" to the versions you downloaded
echo -e "export PATH=\$PATH:$HOME/namecoin-nc22.0/bin\nexport PATH=\$PATH:$HOME/ncdns-0.3-linux-x86_64-e41ca2/bin" >> .bashrc
source $HOME/.bashrc

edit /etc/resolv.conf (sudo), add at the beginning of file:
nameserver 127.0.0.1

nameserver needs to be able to bind to port 53
sudo setcap CAP_NET_BIND_SERVICE=+ep ncdns

start it (username and password doesnt matter, its localhost):

namecoind -rpcuser=username -rpcpassword=password
ncdns -ncdns.bind 127.0.0.1:53 -ncdns.namecoinrpcusername username -ncdns.namecoinrpcpassword password

test

curl namecoin.bit
curl bartsch.bit
firefox http://bartsch.bit

debugging
if you get this error:
[ERROR] ncdns.backend: failed to query namecoin: stat : no such file or directory
the error message is bullshit, real error is that rpc login failed, check that namecoind and ncdns uses same username and password