Defined but not used: ‘runRoot’

In the use of ‘head’

Failed to parse D:\a\sandwich\sandwich\sandwich-contexts\test\Spec\NixContexts\PostgreSQL.hs: ParseFailed (SrcLoc "D:\\a\\sandwich\\sandwich\\sandwich-contexts\\test\\Spec\\NixContexts\\PostgreSQL.hs" 7 1) "Parse error: import"

The qualified import of ‘Data.Set’ is redundant