Content Addressable Files over Bitcoin

C:// is an immutable URI scheme for referencing B:// protocol files, a simple Bitcoin file storage protocol.

The file system is constructed from Bitcoin transactions, and is instantly serviced through HTTP/HTTPS endpoint.


Having immutable files on the blockchain is not enough, since you still have to trust the server that is providing the file itself. However, if you have a hash of the file contents, you can build deterministic applications. This means that you can be certain that you are working with the file system and content that you need without risk.
Further the blockchain cannot get hacked. You have bullet proof applications – now possible.
If files can be immutably stored AND deterministically served, we can build absolutely deterministic applications. 

We can even treat them like local files because it’s now possible to use ANY 3rd party file server WITHOUT having to trust them. 

C:// deals only with the referencing part.

  • Write: Write with B://, a simple protocol for writing immutable files to Bitcoin
  • Read: Read with C://, a content addressed URI scheme for B:// files. The URI is derived from the content.

Instead of using the B://{{transaction id}} URI scheme, you use the new C://{{sha256(content)}} to store and serve files. An example HTTP implementation:{{SHA256(content)}}

With C://, you can use any Bitcoin file serve provider WITHOUT having to trust them at all, because you can effortlessly verify the authenticity 100% client-side. All you need to do is compare the URI with the SHA256 of the file itself.