Proven immutable data stored on the Steem blockchain

#3 Product of the DayFebruary 04, 2019's service is pretty straightforward. If you have a document of which you want to know with 100% certainty that it's contents has not been changed, tampered with or altered in any form, use works by fingerprinting your file (no matter how big), without the need to upload it, inside your browser.

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13 Reviews5.0/5
Hi Product hunters! Last week on cryptotwitters @btsfav was requesting a blockchain based product which I thought would be cool to make! A simple blockchain (proof of time) storage of file hashes to proof file integrity based on a trustless environment. And this is what I made - - a 24hr weekend endeavour using all tools out there: - Developer SDK's - - thank you @bramk for reminding me - Bootstrap, Cryptojs and Filehashing, Filesaver.js - I think is a nice little web app focussing on 1 thing only, namely generating an offline file hash/fingerprint and optionally storing it on the Steem blockchain for proof of time. You can use it for example in fav's usecase: "So I got a signed PDF, and all parties need to be able to verify the hash on chain via a tool to check whether it's still the original file". Thanks @fav for the inspiration! Let me know what you think?
@roelandp This is such a brilliant idea!
@roelandp "So I got a signed PDF, and all parties need to be able to verify the hash on chain via a tool to check whether it's still the original file" - this is a scenario I have came across many times. Few days I came across a solution for the shipping industry where "Title deed", Bill of Lading etc are handled using a blockchain based solution. This can be extended to such use cases IMHO. Also the best part I see is that this on a public blockchain in the true sense of "public ledger" ideology as opposed to be on a "private chain".
@bobinsonkb oh yes that shipping thing is interesting. And you have all the "provenance" initiatives. I like the Steem chain indeed for being available publicly and also the fast confirmation times and fee-less posting, which has low entry barriers for users to start using services like these 😉

Steem Blockchain has some brilliant qualities and is worth looking into.


Built on the immutable Steem Blockchain but a talented developer


Early days - more users will arrive

thank you for the review 🙇
This is a nice little app that utilizes Steem blockchain in a brilliant way :) Love it!

The users can either 'proof' something, simply by uploading a file, or 'validate' a file!


I think that this product comes to solve a common issue. Easy to use, it can be used by a variety of individuals or even businesses.


It needs to be communicated and promoted.

Steem as a blockchain platform offers the ideal environment for building social and crowd-related Dapps. The platform has an already existing community of users to increase Dapp adoption and utility with little cost.


Built on a proven/scalable blockchain Steem. Blockchain immutability feature accredits product's credibilty and integrity. Easy to use.


Early days... Will get better with more use and reviews.

Thank you Mainframe for your comments.