Depthline is built around a simple idea:

You write something true, send it into the ether, and let it find the person it's meant to find.

A thought.
A confession.
A question.
A tiny win.
A heavy night.
A feeling you don't want to turn into a post.

Depthline gives that message somewhere to go.

Not a stage.
A current.

Depthline is built for honesty, tenderness, and human contact.

You can be messy here. You can be lonely, confused, scared, angry, hopeful, strange, tender, or unsure. That's part of being human, and this place exists to give those feelings somewhere to breathe.

The ether has boundaries because people do.

Don't post threats, harassment, hate, sexual content involving minors, private personal information, spam, or anything meant to target, shame, exploit, or endanger another person.

Messages may be removed, held for review, or hidden if they cross those lines. Accounts aren't used here, but abusive access can still be blocked.

Depthline may also use automated review tools to help flag messages before they appear publicly. If the ether gets noisy or unsafe, moderation may become stricter for a while, including requiring approval before messages appear.

The goal is not to make Depthline sterile.
The goal is to keep it human.

Honest is welcome. Cruel is not.

When you throw a message, it floats in the ether — visible to other people browsing the feed — until someone finds it and chooses to respond.

That response opens a private conversation between the two of you.

When someone opens your message to reply, Depthline holds it for them for up to 5 minutes. During that time, it disappears from the feed, giving them a small protected space to write back.

If they send a reply, the conversation begins.

If they pass, leave, or the timer runs out, your message returns to the ether.

If nobody responds within 7 days, the message expires and returns to your inbox marked “returned.”

From there, you can throw it again.
You can rewrite it.
You can let it go.

A returned message is not a rejection.

It just means the current didn't catch it that time.

Depthline does not use accounts.

No email address. No password. No username. No profile.

When you first visit, your browser quietly generates a random ID — something like a3f9bc02-7d1e-... — and stores it in your browser's localStorage.

That random ID is your Depthline identity.

It lets the app remember your throws, conversations, blocks, reports, and recovery phrase without asking for your name or email.

This means:

This is by design.

Depthline gives your messages a temporary home without asking you to build a public self around them.

Every Depthline identity comes with a recovery passphrase — four words, something like tide · ember · hollow · glass.

You can find yours at the bottom of your inbox.

That passphrase is the only way to carry your identity across devices or browsers. If you want to use Depthline on your phone and your laptop as the same person, enter your passphrase on the restore session page.

Write it down somewhere safe. Screenshot it. Treat it like a password.

If you lose it, there is no recovery.

The passphrase is the identity.

Without it, a new device becomes a new person.

Depthline stores the minimum needed to make the app work.

That's it.

Depthline does not store read receipts. It does not show typing indicators. It does not build profiles from what you write. It does not run analytics on your message content.

To prevent abuse, Depthline counts how many messages are thrown from each IP address per day. This count resets at midnight and is not linked to your random ID in any other way. It is not stored beyond the current day.

The database runs on Cloudflare D1, a serverless SQLite product. Cloudflare's own infrastructure logging may record request metadata — such as IP addresses and timestamps — at the network level. That happens outside Depthline's direct control.

Messages in the ether expire after 7 days if nobody responds.

There is no manual cleanup button. The server marks old messages as expired the next time someone loads the feed.

When someone opens your message to respond, it is held for 5 minutes. If they navigate away, hit pass, or the timer runs out, the message returns to the ether automatically.

The current keeps moving.

No message gets stuck forever.

Once someone replies to your message, a private conversation begins.

That conversation stays in both users' inboxes until it is ended.

Either person can end, report, or block at any time.

Ended conversations stay visible in your inbox as a record, but they can't be continued.

Every connection on Depthline begins from the ether.

You send something real. Someone answers. For a little while, there is a thread.

Depthline is private by shape, anonymous by design, and temporary where it needs to be.

It is not built around followers, faces, likes, or performance.

It is built around the message.

The strange one.
The honest one.
The one you almost didn't send.

You throw it into the ether.

Somewhere, someone may find it — not because they know who you are, but because something in what you wrote reached them.