Add builds via builder-db command?

[reynir]

Currently, the only way to populate a builder-web instance is by running builder-web and uploading builder execution files. This requires having set up a user with builder-db add-user first while ensuring correct permissions. For testing purposes it could be nice to be able to do it directly with the builder-db command. However, this might require quite a bit of code changes.

[hannesm]

\o/