Survival Engineers is a Space Engineers Server

From the devs:

Summary
Pistons have been added in Space Engineers - they can be used to build advanced machinery. Also, faction founders and leaders can now enable auto-approval for new members. Players will now be able to see a notification on HUD when somebody is hacking/grinding their ship (does not apply to armors). Thrusters can be used without cockpit - through the terminal - which enables the option to create missiles with warheads, turret countermeasures, small drones which grind enemy ships by using grinder and other. Blast door blocks has been also added in the game; it's similar to armor, but thinner, so it can slide between two layers of armor (very useful for airtight door and hangar bays).