To host a local repository for Chocolatey either as server for self-hosted packages or as proxy server for any NuGet server/the official chocolatey repository server we use Solartype Nexus3: sonatype.com - Nexus3. Nexus3 is also useable for hosting a simple, easy-to-manage repository for the APT-package manager.

1. Download Debian 12 Server from here: debian.org/distrib and install your machine.
2. Install Java 17:

   sudo apt install openjdk-17-jdk

3. Add user nexus to run Nexus3:

   adduser nexus

4. Download the latest Nexus3 from https://help.sonatype.com/en/download.html
5. Unpack it to /opt/:

   tar xzvf <downloaded-tar-package>.tar.gz -C /opt

6. Change owner of unpacked files:

   chown nexus -R /opt/nexus-<version>

7. Make binary executeable:

   chmod +x /opt/nexus-<version>/bin/nexus

8. Create systemservice with the name nexus.service and copy it to /etc/systemd/system (keep in mind to add the nexus version):

   nexus.service

   [Unit]
   Description=nexus service
   After=network.target
    
   [Service]
   Type=forking
   Environment="NEXUS_SECRETS_KEY_FILE=/opt/sonatype-work/nexus3/keystores/nexus.secrets.json"
   LimitNPROC=65536
   LimitNOFILE=65536
   ExecStart=/opt/nexus-<version>/bin/nexus start
   ExecStop=/opt/nexus-<version>/bin/nexus stop 
   User=nexus
   Restart=on-abort
   TimeoutSec=600
    
   [Install]
   WantedBy=multi-user.target

   cp nexus.service /etc/systemd/system

   systemctl start nexus.service

   systemctl enable nexus.service

9. When everything was successful, enter the webservice with http://<ip>:8081/
10. The password for admin is located under /opt/sonatype/sonatype-work/nexus3/admin.password after entering the password, it's forced to be changed.

    cat /opt/sonatype/sonatype-work/nexus3/admin.password

    The installation of Nexus is now finished!

To add a new NuGet (Chocolatey) repository proxy add a new nuget (proxy). To proxy the official Chocolatey repository add the following URL as URL:

https://community.chocolatey.org/api/v2/

Finally save the proxy repository.

If the repository should also host packages locally add a new nuget (hosted).

To make the proxy-repository and all local hosted packages available through one URL, add a nuget-group on the repository tab. Then add both nuget-proxy and nuget-hosted to the group.

Sourced from:

• github.com/sonatype-nexus-community
• howtoforge.com - install Nexus3 on Ubuntu22
• stackoverflow.com - Nexus serve up chocolatey