There is a new pull request by tranzystorek-io against master on the void-packages repository

https://github.com/tranzystorek-io/void-packages cargo-sparse-index
https://github.com/void-linux/void-packages/pull/43172

common/build-style/cargo.sh: switch to sparse index protocol
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#### Testing the changes
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A patch file from https://github.com/void-linux/void-packages/pull/43172.patch is attached