BLESS
An SSH Certificate Authority that runs as an AWS Lambda function
...Instead of managing the authorized_keys of a host, or controlling who has access to SSH Private Keys, hosts just need to be configured to trust an SSH CA. BLESS should be run as an AWS Lambda in an isolated AWS account. Because BLESS needs access to a private key that is trusted by your hosts, an isolated AWS account helps restrict who can access that private key, or modify the BLESS code you are running. AWS Lambda functions can use an AWS IAM Policy to limit which IAM Roles can invoke the Lambda Function. If properly configured, you can restrict which IAM Roles can request SSH Certificates.