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Ledgerlets API

An API for a free service to create proof of existence evidence for documents and files on the blockchain.


Problem: You need to create a proof that you owned a certain document or picture at a specific point in time. This can be a commercial agreement or a contract, a 'source' for an investigative article you're working on or a picture that captures an important situation in a specific time. You can do this today by creating a hash and storing it on the bitcoin or ethereum blockchain but that can become quite expensive if you have tens or more files. Furthermore, this method is highly inefficient and can cause congestion on the blockchain. Ledgerlets aim to solve this problem by creating hourly batches of file hashes and only store the hash of the list on the blockchain. It adds one more step to the process, but the main value is the ability to offer this service for free and to avoid "spamming" the blockchain with a transaction for each document proof

How It's Made

There are 2 operations provided in this API. A POST action that takes a SHA256 signature and stores it in an hourly batch file A GET action that takes a SHA256 signature and provides information of when the file was "signed" on the blockchain and what's the supporting batch file There's also a runner in the background that does all of the work of signing the batch file.

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