Guides

Database Setup

The c15t backend requires a database to store consent records, subjects, audit logs, and policies. Five adapters are supported — choose the one that matches your existing stack.

Adapters

Kysely

c15t.ts

import { c15tInstance } from '@c15t/backend';
import { kyselyAdapter } from '@c15t/backend/db/adapters/kysely';
import { Kysely, PostgresDialect } from 'kysely';
import { Pool } from 'pg';

const db = new Kysely({
  dialect: new PostgresDialect({
    pool: new Pool({ connectionString: process.env.DATABASE_URL }),
  }),
});

export const c15t = c15tInstance({
  adapter: kyselyAdapter(db),
  trustedOrigins: ['https://example.com'],
});

Drizzle

c15t.ts

import { c15tInstance } from '@c15t/backend';
import { drizzleAdapter } from '@c15t/backend/db/adapters/drizzle';
import { drizzle } from 'drizzle-orm/node-postgres';

const db = drizzle(process.env.DATABASE_URL);

export const c15t = c15tInstance({
  adapter: drizzleAdapter(db),
  trustedOrigins: ['https://example.com'],
});

Prisma

c15t.ts

import { c15tInstance } from '@c15t/backend';
import { prismaAdapter } from '@c15t/backend/db/adapters/prisma';
import { PrismaClient } from '@prisma/client';

const prisma = new PrismaClient();

export const c15t = c15tInstance({
  adapter: prismaAdapter(prisma),
  trustedOrigins: ['https://example.com'],
});

TypeORM

c15t.ts

import { c15tInstance } from '@c15t/backend';
import { typeormAdapter } from '@c15t/backend/db/adapters/typeorm';
import { DataSource } from 'typeorm';

const dataSource = new DataSource({
  type: 'postgres',
  url: process.env.DATABASE_URL,
});

export const c15t = c15tInstance({
  adapter: typeormAdapter(dataSource),
  trustedOrigins: ['https://example.com'],
});

MongoDB

c15t.ts

import { c15tInstance } from '@c15t/backend';
import { mongoAdapter } from '@c15t/backend/db/adapters/mongo';
import { MongoClient } from 'mongodb';

const client = new MongoClient(process.env.MONGODB_URI);

export const c15t = c15tInstance({
  adapter: mongoAdapter(client),
  trustedOrigins: ['https://example.com'],
});

Migrations

To create & update the database you can use the migrator which is included in the CLI:

npx @c15t/cli

Table Prefix

If you share a database with other applications, use tablePrefix to namespace the c15t tables:

c15tInstance({
  adapter: kyselyAdapter(db),
  tablePrefix: 'c15t_',
  trustedOrigins: ['https://example.com'],
});

This prefixes all table names (e.g. c15t_subject, c15t_consent, c15t_audit_log).

Schema Overview

The backend creates and manages these tables:

Table	Purpose
`subject`	Consent subjects (users/devices). Tracks identification status and external IDs.
`consent`	Append-only consent records. Stores preferences, jurisdiction, IP, and timestamps.
`domain`	Domain/website configuration for multi-domain setups.
`consent_policy`	Versioned consent policies.
`consent_purpose`	Maps consent purposes to categories.
`audit_log`	Immutable log of all consent-related actions.