---
title: Backend overview
description: What the c15t consent backend does, and when to use Inth or run
  @c15t/backend yourself with your own SQL database.
group: self-host
lastModified: "2026-10-10T16:01:45+01:00"
---
## Start with Inth

[Inth](https://inth.com) is the recommended backend for c15t applications. Use
the endpoint supplied by your project in the [framework quickstart](/docs/frameworks).
You get a backend connection without running the SQL service described in these
guides.

Self-hosting runs `@c15t/backend` in your own server, and your app connects to
it with the same hosted mode it would use for Inth. Choose it when you need to
operate the service yourself. You own database provisioning, migrations,
backups, policy configuration, signing secrets, availability and upgrades.

## What the backend provides

|Capability|How clients use it|
|--|--|
|Reusable configuration|`/manifest` publishes policy rules, translation configuration and IAB metadata for caching and local resolution.|
|Request initialization|`/init` resolves the policy for a request's location, language and privacy signals.|
|Consent persistence|Subject endpoints record confirmed category receipts and retrieve current choices.|
|Identity links|`PATCH /subjects/:id` links a device subject to an external identity, such as a signed-in account.|
|Legal-document versions|An authenticated release endpoint stores the current document identity. Exported helpers sign and verify document snapshots.|

For Next.js request rendering, prefer the cached manifest path described in
[data fetching](/docs/concepts/data-fetching). A browser-only application can use
regular initialization. A static frontend can use either Inth or a separately
deployed self-hosted backend; static hosting does not require offline mode.

## What offline mode changes

`offline()` resolves policy in the browser and keeps choices in browser
storage. It never calls a backend, so no consent records exist and policy lives
in your code. Use it for local development and tests. Not recommended for
production environments. See [choose your setup](/docs/concepts/choose-your-setup).

## Operate your own backend

Start with the [self-hosted quickstart](/docs/self-host/quickstart), then review
[database setup](/docs/self-host/guides/database-setup) and
[configuration](/docs/self-host/api/configuration). Use
[HTTP endpoints](/docs/self-host/api/endpoints) to integrate a custom server
client, and [policy configuration](/docs/self-host/guides/policy-packs) when you
own the policy manifest.