Can the Merkle tree guarantee that a commit hasn't been tampered with?
The hash chain provides integrity within a repository: changing any file requires recomputing every ancestor hash up to the commit, which would alter the commit hash. An attacker would need to forge a new commit hash. For remote repositories, you verify the commit hash through HTTPS (PKI) or by comparing against a trusted copy. The Merkle structure makes tampering expensive but doesn't prevent it remotely without an authenticated channel.
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Merkle Trees: How Git Detects Changes in MillisecondsGit hashes files into nested cryptographic trees to skip unchanged directories in one comparison, finding changes across millions of files faster than scanning.
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