To implement a passwordless login using a one-time code sent via email in Ory Kratos, you need to follow these steps: 1. Specify the email field as the identifier for the one-time code strategy in the Identity Schema. This can be done by setting the

identifier

field to

true

and the

via

field to

email

under the

code

credentials in your identity schema. Here is an example:

json {   "<http://ory.sh/kratos|ory.sh/kratos>": {     "credentials": {       "code": {         "identifier": true,         "via": "email"       }     }   } }

(Source: [Customize identity schemas](https://www.ory.sh/docs/kratos/manage-identities/customize-identity-schema#passwordless-one-time-code-login-identifier)) 2. Ensure you have a reliable email delivery provider. This is crucial for the reliable delivery of one-time codes. You can set up your own SMTP provider for full control over the email delivery process. More information on this can be found [here](https://www.ory.sh/docs/kratos/emails-sms/sending-emails-smtp). 3. Customize the login and registration email templates to match your brand. More information on how to do this can be found [here](https://www.ory.sh/docs/kratos/emails-sms/custom-email-templates). Please note that when implementing the one-time code strategy, MFA via code to SMS/email cannot be used for passwordless login if it is enabled ([source](https://www.ory.sh/docs/kratos/mfa/mfa-via-sms)). For more detailed information, you can refer to the [Ory Kratos Passwordless Authentication with One-Time Code](https://www.ory.sh/docs/kratos/passwordless/one-time-code) guide.