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PoEx on NPM

Mon, 26 February 2018

We have long made use of free and open source software, programming languages, and blockchain libraries and tools. Now it’s our chance to give back.

We’ve staked our claim on with the @poexio organization scope, which will be our conduit for releasing software for the JavaScript and Node.js ecosystems.

We’ve just released @poexio/blockcypher, a flexible Node.js client for the BlockCypher API and a fork of the official SDK, updated to use native JavaScript ES6 promises, and with a configurable URL endpoint. The code is available under a generous MIT License.

Watch for us on and at our home on GitHub.

Price status info for our API users

Mon, 15 January 2018

As Bitcoin transaction fees have increased sharply in the past year, we have been careful to set a sufficient docproof price so that a proof of existence can be confirmed in the blockchain as quickly as possible, ideally in the next block.

We display the fee denominated in mBTC on the docproof web page (including in a QR code), and in satoshis for our API users when they register a hash. However, the exact price was missing when checking the status of a docproof via our API. This has been remedied in our most recent update.

While we are committed to keeping version 1 of our API stable, we haven’t stopped working on new features to bring you in 2018.

Happy New Year from the PoEx Team!

Check your proofs with Bitcoin Testnet

Fri, 10 November 2017

If you’re new to Bitcoin or just wanting to experiment with blockchain applications, there’s an alternative Bitcoin blockchain called Testnet that is free to use.

If you want to try out our Proof of Existence service before committing to a transaction on the main Bitcoin blockchain, we have deployed a copy of the site at that accepts Testnet coins and creates docproofs on the Testnet3 network.

The advantages of using Testnet are that transactions tend to be confirmed faster, and it does not require buying or spending real bitcoins.

There are some disadvantages, however. Since Testnet is used for serious protocol stress-testing and even network attacks, it can perform erratically and become unreliable.

You should also be aware that Testnet could change at any time and so does not guarantee a proof of existence in the way that the real Bitcoin blockchain does.

Nevertheless, there is no risk to trying it out. We invite you to use for sampling our service or testing your applications in a live environment.

The Testnet wiki page has more information on how to create and fund a testnet wallet.

HB436 signed and placed on Bitcoin blockchain

Mon, 2 October 2017

New Hampshire House Bill HB436, which exempts persons using cryptocurrencies like Bitcoin from registering as money transmitters, was signed into law by Governor Chris Sununu in June 2017.

With the assistance of one of the bill’s sponsors, NH State Legislator Keith Ammon, the Governor’s office used PoEx’s Proof of Existence service to attest the text of the bill on the Bitcoin blockchain by embedding the cryptographic hash of the PDF in a confirmed transaction.

Rep. Michael Costable Jr. also posted a video of the crypto bill signing on Facebook.


Wed, 13 September 2017

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