Migrating from Clerk to Kernia

Move Clerk users, organizations, sessions, social accounts, and MFA into Kernia.

A Clerk migration usually involves users, organizations, memberships, invitations, social accounts, phone numbers, email verification, and MFA state. Treat it as a staged data migration with a frontend cutover, not a find-and-replace of SDK calls.

Inventory

Export or enumerate:

Users, primary email, verified emails, usernames, and phone numbers.
External accounts and provider account ids.
Organizations, memberships, roles, and invitations.
MFA methods and whether they can be migrated safely.
Active sessions and device state.
Webhook consumers that currently depend on Clerk events.

Kernia setup

auth.py

from kernia.plugins.organization import organization
from kernia.plugins.username import username
from kernia.plugins.phone_number import phone_number
from kernia.plugins.two_factor import two_factor

auth = init(KerniaOptions(
    database=adapter,
    secret=env.KERNIA_SECRET,
    base_url=env.KERNIA_BASE_URL,
    plugins=[
        organization(),
        username(),
        phone_number(send_sms=sms_client.send),
        two_factor(),
    ],
))

Mapping

Clerk	Kernia
User	`user` row.
Email address	User email and verification state.
External account	`account` row.
Organization	Organization plugin tables.
Membership	Membership rows with role mapping.
Invitation	Organization invitation rows.
MFA	Two-factor and passkey plugins where supported.

Passwords and sessions

If password hashes are not exportable in a supported format, require password reset or staged reauthentication. Do not claim silent password migration unless you can verify the exported hash format and rewrite it into Kernia after sign-in.

Active Clerk sessions usually should not be imported. Plan a sign-in cutover and keep the old system available only long enough to finish migration.

Frontend changes

Replace Clerk UI components with calls to Kernia routes or the compatible JS client. Keep protected backend data behind Python route checks, not frontend-only auth guards.

Webhooks

Replace Clerk webhook consumers with Kernia hooks or audit events. If billing, provisioning, or CRM sync depends on Clerk user events, replay the equivalent Kernia events in staging.

Validation

Test email sign-in, social sign-in, organization switching, role checks, invitation accept, phone verification, MFA enrollment, logout, and account deletion before production cutover.