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The helm package command from Helm versions before 4.0.0 cannot produce non- reproducible archives.
Since Helm version 4.0.0, it is possible to produce reproducible archives, even with the --sign option. The package archive entries get a constant uid/gid and fixed POSIX permissions. The file modification time is set to the source files' modification time.
Consider setting a constant file modification time, for example using find $PACKAGE_CONTENTS_DIRECTORY -exec touch -d "2000-01-01 00:00:00" {} +
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