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  * [the release notes]source:relnotes.txt@1346 announcing v0.6 on September 24, 2007, including improved performance and packaging
 
 ## Detailed Design Docs
+ * [mutable.txt]source:docs/mutable.txt, explaining the interesting crypto tricks that go into secure distributed mutable files
  * [FileEncoding](FileEncoding), explaining how we turn files into shares, with verifiable hashes; This is mostly concerned with chunking and Merkle trees.
  * [ShareEncoding](ShareEncoding), explaining how we turn a chunk into shares: Reed-Solomon, FEC, that stuff