Matrix is a pure vanilla server, made for people who want to get back to the roots of what Vanilla is supposed to feel like. Don't come expecting /sethome, /home, /tpa, or the usual convenience stuff, because even though those kinds of commands exist in vanilla, we feel they take away from the original game.
The map is limited to 50k in every direction for building, with the space beyond that kept for custom trade villagers, games, and other extra stuff. Any fancy tricks or commands we do have are handled with command blocks, and everything has been tested to work properly in 1.15.
If you're looking for a straightforward survival world with a vanilla feel, Matrix keeps it simple on purpose. There's still room for building, exploring, and messing around with the extra features outside the main build area, but the core idea stays the same: keep it close to real vanilla.