Installing Crimson manually over Byzantium

[dos]

@tracy

gcc-7-base (7.5.0-5)

See:

PureOS Crimson Development Report: January and February 2026 – Beta Released

gcc-7-base used to be present in PureOS 9 (amber). Usually such packages would have been removed automatically once they’re made redundant, but apparently it didn’t happen in your cases.