The Highway MASA is a ruby-on-rails web application.
It provides operator access to create IDevID certificates, storing the resulting public parts into a database. A manufacturer would run this part, and then install the public and private key pairs into a device as part of the assembly line, perhaps via a JTAG interface that initializes the firmware content, or perhaps as the last step of a quality assurance initial boot.
The release 0.50 of the Highway MASA supports PKCS7 signed voucher requests, and generates PKCS7 signed vouchers. It does no supply chain management, and likely has some logic missing to do all of the required nonce processing.
This release does not provide the audit log functionality.
There are few negative (challenge, or attack) test cases.
The above limitations are not a result of planning or intent, but just the result of getting an initial set of green tests done.
As part of the Minerva project two public MASA have been set up.