I know hardcoe is about drinking, and eating, and slow stempacks...
However can you do hardcoe without your companions dieing?

I like the idea of drinking, and eating, but on my first play through my NPC friends seem to do... stupid things >.>.
I plan on going explosives + melee, and I am sure far more then once a companion will rush in right when I throw my bomb /sigh .

From what I've heard; companion death = permanent in hardcoe.

Companions can die when playing with hardcoe on. If you're on the PC you can probably set them essential with console commands.

You should also look into Spray N' Pray

Yes, they can die. Armor them up, watch their health.

Yep they can. Lost Boone on my way to vault 22 by swarm of rapist bees. Barely escaped with both legs, right hand, head and torso crippled. Managed to kill few of those fragging insects with few frag mines and frag grnades. Was on lvl 12 at that time. Gonna head there soon with ED-E and Cas and give them some payback!

I lost ED-E outside Vault 22 by some Cazadors. I lost Boone at Black Mountian via Super-Mutant with Incenerator...

There's like 3 mods in the new vegas nexus that lets you flag all companions as essential, so no permanent death. Highly recommend if you don't like that aspect of HC.