K. Corporation

Publicly accessible:

This Website: Pure HTML and CSS, no JavaScript garbage. Lightweight, functional, no stupid slow animations that destroy the website when opened on a 4:3 monitor.
Plik (Source Code): A temporary file upload system, provides a lot of features and is written in Go.; It allows multi-file upload and time limitations or destroy-after-download options; Currently, the file size limit is 20GB.
SearX (Source Code): A Metasearch engine, meaning it gathers the search results of multiple search engines.; The user can customize almost anything, their setup is saved in the cookies or in a generated search URL.
Matrix/Synapse (Webpage): Matrix is a decentralized communication protocol, providing great privacy and independence.; You can integrate Bots, Bridges to other services and other awesome features.; The Synapse Server is one of multiple options for a matrix homeserver. It is the largest and most refined variant and consumes a fairly small amount of ressources.

If you use and like these services, consider donating some pennies to their creators. If you feel extra generous, feel free to donate some money to me. However, I created this site and host those applications because I wanted to learn the process and to use them myself and I am not dependent on any donations.

Private Services:

Mail Server (Postfix, Dovecot, OpenDKIM): My own Mail Server, capable of sending and receiving mail from everywhere.; Postfix is a minimal mail server, responsible for transfering the data.; Dovecot is a IMAP server with top-of-the-line security. It's job is to store the mail and make it accessible for the client.; OpenDKIM allows DKIM authentication, needed for secure mail transfer. Without it, your mails would be blocked by big providers like Gmail etc.; Recently, I've added SpamAssassin, created by Apache. This filters spam mails with customizable domain lists.
SyncThing (Source Code): A file synchronization program.; In contrast to a cloud, SyncThing creates actual copies of the desired files and synchronizes them between devices, making them available offline on all devices.; I mainly use SyncThing for music, documents and some programming stuff.
Nextcloud (Source Code): Nextcloud is a full on cloud service with many features.; The admin can integrate many apps like calendar, Element, Kanban and others.; It is like GDrive, but better, cheaper and more customizable.
Gitea (Gitea): Not much to explain. It is a Git Server, so that I can keep my stuff in my own hands.; I use Gitea, because it provides a great UI and isn't too heavy.; Other alternatives would have been GitLab or cgit, but Gitea has a good balance.

These services are not publicly accessible, because it would exceed my budget and resources to make it available to everyone. I also run some services on a local homeserver like piHole, Unbound, Snowflake, Octoprint and Jellyfin, but they are not directly accessible from the outside world.

Maybe I'm going to write a more detailed description of the services, their installation and everything else, but I don't have time for that right now.