Joining a Tilde

Joining a Tilde

How to get an account on a shared unix server, make the SSH key you need, and stay safe once you are in. Adapted from the tilde repo wiki.

Why Join

A real linux or BSD system to learn on, usually free
Your own page at host/~you on the web, and often gopher or gemini too
IRC chat, games, mail, and tools written by your neighbours
Small communities run by volunteers: no ads, no tracking, human scale
A tradition in continuous use going back to 1960s timesharing (see Pubnix History)

Pick a Server

Browse the member list at tildeverse.org/members. A quick guide by temperament:

tilde.town: the most community features and built-in tools; slower, careful manual signup
tilde.club: a plain, standard unix box
tilde.pink: gopher and gemini culture
envs.net: minimalist, long service list, popular
tilde.team: teaching and learning unix
cosmic.voyage: collaborative science-fiction writing
rw.rs: experimental, minimal, 199X aesthetic; open source and free to join
sdf.org: not a tildeverse member, but the original pubnix; signup is fast and many services become available with a one-time membership payment

Each host's signup page is linked from its homepage. Signup asks for a username (lowercase; it becomes your ~name everywhere), an email address, your SSH public key, and sometimes a sentence about what you want to do. Approval is manual on most tildes: expect days, not minutes.

Make an SSH Key

SSH replaces passwords with a key pair: the private key stays on your computer, the public key goes to the server.

ssh-keygen -t ed25519 -C "you@example.com"

Accept the default path ~/.ssh/id_ed25519
Set a passphrase; it protects the key if your computer is lost
Send the server only the .pub file: cat ~/.ssh/id_ed25519.pub
The file without .pub is private and never leaves your computer

Already have a key? Reuse it, or make a second one just for tildes: ssh-keygen -t ed25519 -f ~/.ssh/id_ed25519_tilde. A host entry in ~/.ssh/config keeps logins short:

Host tilde.town
    User yourname
    IdentityFile ~/.ssh/id_ed25519

First Login

The first connection asks you to trust the server's host key: type yes
If the host issued a password, change it with passwd
Create your site directory if needed: mkdir public_html && chmod 755 public_html (check the host's docs for the right name)
Write ~/.plan and ~/.project files; test with finger yourname@host
Read the motd, the host's wiki, and say hi on IRC

Staying Safe on a Shared Machine

A tilde is one computer that many people share. Assume little is private.

chmod 700 ~ makes your home directory private, but check the host's norms first: some tildes expect readable homes for finger and .plan culture
Assume everything under public_html, public_gopher, and public_gemini is public, because it is
Never store passwords, private keys, or API tokens on the shared host
Use one keypair per device: if a device is lost, you revoke only that key
Put a passphrase on every private key; ssh-add loads it into ssh-agent so you type it once per session
Check ~/.ssh/authorized_keys occasionally for entries you do not recognize
Turn on two-factor login where offered (tilde.club supports TOTP via .google_authenticator)
Keep your signup email current so admins can reach you

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