Following up on #41750 and #41751. Thanks to the efforts by @jellybob there is potentially a new version of mimemagic, see jellybob/mimemagic#3. The library will read the mime database at runtime from the database file if the file is present on the system. The database can usually be installed with the system package manager. With this approach it is compliant to release the gem as MIT licensed again. We could release this version as 0.3.7. However it is still expected that there is some disruption to be caused by the new installation method; and also depending on if 0.3.6 is yanked once again or kept around.

Since you seem to be working on another solution (comment by @georgeclaghorn #41750 (comment) and comment by @rafaelfranca #41751 (comment)) it would be good to hear your opinion on this.

See also rails/marcel#23 and rails/marcel#26.