blockchain official documentation I am developing a system of administrative management. The project is migrating from PHP to C ++. With the new requirements we want to work with blockchain. But when looking for more about it, despites generic tutorials, I almost always find links to blockchain implementations like Bitcoin or Eterium. But I need to implement something pure, from scratch.

Where can I find the official documentation of blockchain technology ??
Where can I find the official documentation of blockchain technology


Nowhere. There is no official body in charge of "blockchain technology". 

There are many different individuals, groups and organisations all doing their own "blockchain" work more or less independently. They will often base their blockchain partly on older blockchain ideas. Each of these groups may or may not publish a definition of the blockchain they are using.

One example is the Bitcoin Developer Reference written by some ever-changing random group of mostly anonymous/pseudonymous people whose motives and accuracy you have to make your own judgement about. I suspect they are mostly OK but you have no recourse if I or they are wrong misleading or even maliciously deceptive.

The nearest thing to an official definition would probably be Satoshi Nakamoto's white paper published in October 2008. If you read and understand that, you are well-placed to implement your own blockchain. You'll need a grounding in basic cryptographic principles and algorithms (don't write your own cryptographic algorithms).


  we want to work with blockchain.


If this comes from marketing, ignore them and just add the word "blockchain" liberally to product names, documentation etc :-)

Note that The Economist Sept 1st 2018 has a 12-page section on blockchain

Although mostly positive about blockchain, it does have many cautions.


  because of its decentralised nature, a blockchain will always be slower and more cumbersome than a standard database.


Their separate lead article says:


  A few organisations, such as SWIFT, a bank payment network, and Stripe, an online payments firm, have abandonded blockchain projects, concluding that costs outweigh benefits. Most other projects are experimental.


The idea of replicated peer-to-peer databases with strong controls on integrity based on public-key cryptography goes back to at least 1984 when Ray Ozzie et-al formed Iris associates to develop Lotus Notes. Anyone selecting "blockchain" needs to have a deep understanding of which of it's characteristics are vital to their project, what alternatives exist and what the trade-offs are.