Write some Software

I would like to build simple web based application which will calucate 256sha hash of some document or digital file and send the hash of the file to the bitcoin network after. 1. Need to calculate 256sha hash of some document/file in browser via simple web UI. [login to view URL] 2. Cryptographic hash of the entire document, is after stored in a 40-byte slot included in every bitcoin block, called OP_RETURN. That slot can be used for storing messages and other arbitrary data. 3. Once the transaction is confirmed on the blockchain I should be able to check raw bitcoin transaction and its hash to be able to proof that some file existed in some point of time. This application can be quite easily developed using [login to view URL] , bitcoincore and angular.js . Unfortunately I do not have the right skills so someone with experience in cryptography and blockchain apps is needed. One important thing the app should be build on bitcoin blockchain but preferably using another blockchain using the same 256sha cryptography as bitcoin. This blockchain is basically connected with bitcoin network using merged mining technology. I would suggest to check this reddit post, where timestamping discussed in details [login to view URL] I am looking for backend developer who will help with the cryptographic side of the project and make it work with simple frontend which is now being designed and will be coded by my frontend developer.