Assuming you are on a Debian/Ubuntu based distro, make sure you have the following packages installed build-essential golang

However Gotify recomends using docker to build plugins
https://gotify.net/docs/plugin-deploy#with-docker-recommended

make GOTIFY_VERSION=“v2.0.5” FILE_SUFFIX=“for-gotify-v2.0.5” build

Use the gotify version according to the one installed on your system.
EX: make GOTIFY_VERSION="v2.4.0" FILE_SUFFIX="for-gotify-v2.4.0" build
for the latest release

the on build/you should have some .so files, copy the one for your machine arch to gotify plugins dir data/plugins

where a build for gotify v2.4.0 https://nowtransfer.de/3460c8e86670
copy only the one needed

You can get the rss of new releases with rss, and use rss plugin for Gotify
https://github.com/solarkennedy/gotify-rss
https://piraces.dev/short-bits/github-releases-feed-atom/

Debian can also be FreeBSD https://wiki.debian.org/Debian_GNU/kFreeBSD

Unfortunately died last year

Used duckdns for some years, but after some issues migrated to https://desec.io/

• https://desec.io
• https://nsupdate.info
• https://www.duckdns.org

For personal use https://forgejo.org/ or https://gogs.io/ should be enough