Dokuwiki
Dokuwiki is a wiki which stores its content in text files. Having no database makes maintaining it simpler, and it's not tied to any particular domain name so you can easily copy the files to a different domain if you need to.
Installation
Log into your system with:
ssh myusername@mydomain -p 2222
Using cursor keys, space bar and Enter key select Administrator controls and type in your password.
Select Add/Remove Apps then dokuwiki. You will then be asked for a domain name and if you are using FreeDNS also the code for the domain which can be found under Dynamic DNS on the FreeDNS site (the random string from "quick cron example" which appears after update.php? and before >>). For more details on obtaining a domain and making it accessible via dynamic DNS see the FAQ. Typically the domain name you use will be a subdomain, such as wiki.mydomainname.net. It will need to be a domain which you have bought somewhere and own and not one of the FreeDNS subdomains, otherwise you won't be able to get a SSL/TLS certificate for it.
After the install has completed go to Security settings and select Create a new Let's Encrypt certificate and enter the domain name that you are using for Dokuwiki. If you're using the "onion only" version of the system then you don't need to do this. If the certificate is obtained successfully then you will see a congratulations message.
Initial setup
If you have just obtained a Lets Encrypt certificate as above then go to About on the administrator control panel and you should see your Dokuwiki domain listed there along with an onion address. You can then navigate to your site in a browser.
To see the login password for your site go to Passwords on the Administrator control panel and select the appropriate username and app. The passwords will be different for each user and may not be the same as the password which you used to originally ssh into the system.