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https://github.com/eric-erki/awesome-blockchains

A collection about awesome blockchains - open distributed public databases w/ crypto hashes incl. git ;-). Blockchains are the new tulips 🌷🌷🌷. Distributed is the new centralized.
https://github.com/eric-erki/awesome-blockchains

List: awesome-blockchains

Last synced: 16 days ago
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A collection about awesome blockchains - open distributed public databases w/ crypto hashes incl. git ;-). Blockchains are the new tulips 🌷🌷🌷. Distributed is the new centralized.

Awesome Lists containing this project

README 

        

Mining Digital Gold one Block at a Time?! • Don't Expect to Get Insanely Rich (Quick) • Tulips :tulip::tulip::tulip: (like Blockchains) are Great and Gorgeous (and will Endure)  



```ruby

b0 = Block.first(

        { from: "Dutchgrown", to: "Vincent", what: "Tulip Bloemendaal Sunset", qty: 10 },

        { from: "Keukenhof",  to: "Anne",    what: "Tulip Semper Augustus",    qty: 7  } )



b1 = Block.next( b0,

        { from: "Flowers",    to: "Ruben",   what: "Tulip Admiral van Eijck",  qty: 5  },

        { from: "Vicent",     to: "Anne",    what: "Tulip Bloemendaal Sunset", qty: 3  },

        { from: "Anne",       to: "Julia",   what: "Tulip Semper Augustus",    qty: 1  },

        { from: "Julia",      to: "Luuk",    what: "Tulip Semper Augustus",    qty: 1  } )

...

```



(Source: [`blockchain_with_transactions.rb`](blockchain.rb/blockchain_with_transactions.rb))



# Awesome Blockchains



A collection about awesome blockchains - open distributed databases w/ crypto hashes incl. git ;-).  Blockchains are the new tulips :tulip::tulip::tulip:.



Contents:



- [Frequently Asked Questions (F.A.Q.s) & Answers](#frequently-asked-questions-faqs--answers)

- [Do-It-Yourself (DIY) - Build Your Own Blockchain](#do-it-yourself-diy---build-your-own-blockchain)

  - [Python](#python) • [Ruby](#ruby) • [JavaScript](#javascript) • [Java](#java) • [Go](#go)

- [Blockchain Articles](#blockchain-articles)

- [Blockchain Books](#blockchain-books)

- [Blockchain (Lite) Crypto Hash Libraries](#blockchain-lite-crypto-hash-libraries)

- [Git, Git, Git - The Stupid Content Tracker with Crypto Hashes](#git-git-git---the-stupid-content-tracker-with-crypto-hashes)

- [Classic Tulip Mania](#classic-tulip-mania)

- [Awesome Awesomeness](#awesome-awesomeness)



## Frequently Asked Questions (F.A.Q.s) & Answers



**Q: What's a Blockchain?**



A: A blockchain is a distributed database with a list (that is, chain) of records (that is, blocks) linked and secured by

digital fingerprints (that is, cryptho hashes).

Example from [`blockchain.rb`](blockchain.rb/blockchain.rb):



```

[#,

 #,

 #,

  ...

```



![](i/blockchain-jesus.png)



**Q: What's a Hash? What's a (One-Way) Crypto(graphic) Hash Digest Checksum**?



A: A hash e.g. `eb8ecbf6d5870763ae246e37539d82e37052cb32f88bb8c59971f9978e437743`

is a small digest checksum calculated

with a one-way crypto(graphic) hash digest checksum function

e.g. SHA256 (Secure Hash Algorithm 256 Bits)

from the data. Example from [`blockchain.rb`](blockchain.rb/blockchain.rb):



```ruby

def calc_hash

  sha = Digest::SHA256.new

  sha.update( @timestamp.to_s + @previous_hash + @data )

  sha.hexdigest   ## returns "eb8ecbf6d5870763ae246e37539d82e37052cb32f88bb8c59971f9978e437743"

end

```



A blockchain uses



- the block timestamp (e.g. `1637-09-15 20:52:38`) and

- the hash from the previous block (e.g. `edbd4e11e69bc399a9ccd8faaea44fb27410fe8e3023bb9462450a0a9c4caa1b`) and finally

- the block data (e.g. `Transaction Data...`)



to calculate the new hash digest checksum, that is, the hash

e.g. `be50017ee4bbcb33844b3dc2b7c4e476d46569b5df5762d14ceba9355f0a85f4`.



**Q: What's a Merkle Tree?**



A: A Merkle tree is a hash tree named after Ralph Merkle who patented the concept in 1979

(the patent expired in 2002). A hash tree is a generalization of hash lists or hash chains where every leaf node (in the tree) is labelled with a data block and every non-leaf node (in the tree)

is labelled with the crypto(graphic) hash of the labels of its child nodes. For more see the [Merkle tree](https://en.wikipedia.org/wiki/Merkle_tree) Wikipedia Article.



Note: By adding crypto(graphic) hash functions you can "merkelize" any data structure.



**Q: What's a Merkelized DAG (Directed Acyclic Graph)?**



A: It's a blockchain secured by crypto(graphic) hashes that uses a directed acyclic graph data structure (instead of linear "classic" linked list).



Note: Git uses merkelized dag (directed acyclic graph)s for its blockchains.



**Q: Is the Git Repo a Blockchain?**



A: Yes, every branch in the git repo is a blockchain.

The "classic" Satoshi-blockchain is like a git repo with a single master branch (only).



## Do-It-Yourself (DIY) - Build Your Own Blockchain



![](i/fake-dilbert-blockchain.png)



[Python](#python) •

[Ruby](#ruby) •

[JavaScript](#javascript) •

[Java](#java) •

[Go](#go)



### Python



**Let's Build the Tiniest Blockchain in Python Series** by Gerald Nash



- [**Let's Build the Tiniest Blockchain In Less Than 50 Lines of Python (Part 1)**](https://medium.com/crypto-currently/lets-build-the-tiniest-blockchain-e70965a248b), July 2016

- [**Let's Make the Tiniest Blockchain Bigger With More Lines of Python (Part 2)**](https://medium.com/crypto-currently/lets-make-the-tiniest-blockchain-bigger-ac360a328f4d), July 2016



[**Build Your Own Blockchain: A Python Tutorial**](http://ecomunsing.com/build-your-own-blockchain)

by Eric Munsing, March 2017, [(Source)](https://github.com/emunsing/tutorials/blob/master/BuildYourOwnBlockchain.ipynb)



[**Learn Blockchains by Building One (in Python)**](https://hackernoon.com/learn-blockchains-by-building-one-117428612f46)

by Daniel van Flymen, September 2017, [(Source)](https://github.com/dvf/blockchain) -- The fastest way to learn how Blockchains work is to build one



**Build Your Own Blockchain (in Python 3) Series** by Jack Schultz, [(Source)](https://github.com/jackschultz/jbc)



- [**Part 1: Creating, Storing, Syncing, Displaying, Mining, and Proving Work**](https://bigishdata.com/2017/10/17/write-your-own-blockchain-part-1-creating-storing-syncing-displaying-mining-and-proving-work/), October 2017

- [**Part 2: Syncing Chains From Different Nodes**](https://bigishdata.com/2017/10/27/build-your-own-blockchain-part-2-syncing-chains-from-different-nodes/), October 2017

- [**Part 3: Writing Nodes that Mine and Talk**](https://bigishdata.com/2017/11/02/build-your-own-blockchain-part-3-writing-nodes-that-mine/), November 2017



[**A Practical Introduction to Blockchain with Python**](http://adilmoujahid.com/posts/2018/03/intro-blockchain-bitcoin-python/)

by Adil Moujahid, March 2018, [(Source)](https://github.com/adilmoujahid/blockchain-python-tutorial)



### Ruby



[**How Does Bitcoin Force Consensus Among Byzantine Generals?**](http://www.akitaonrails.com/2017/11/01/how-does-bitcoin-force-consensus-among-byzantine-generals) by Fabio Akita, November 2017



[**blockchain-lite - Build your own blockchains with crypto hashes; revolutionize the world with blockchains, blockchains, blockchains one block at a time!**](https://planetruby.github.io/calendar/advent2017/01-blockchain-lite) by Gerald Bauer, Ruby Advent Calendar 2017 / Day 1, December 2017



[**merkletree library - Build Your Own Crypto Hash Trees; Grow Your Own Money on Trees**](https://planetruby.github.io/calendar/advent2017/19-merkletree.html) by Gerald Bauer, Ruby Advent Calendar 2017 / Day 19, December 2017



[**centralbank command line tool (and library) - Print Your Own Money / Cryptocurrency; Run Your Own Federated Central Bank Nodes on the Blockchain Peer-to-Peer over HTTP**](https://planetruby.github.io/calendar/advent2017/24-centralbank.html) by Gerald Bauer, Ruby Advent Calendar 2017 / Day 24, December 2017



### Crystal



[**Write your own blockchain and Proof-of-Work (PoW) algorithm using Crystal**](https://medium.com/@bradford_hamilton/write-your-own-blockchain-and-pow-algorithm-using-crystal-d53d5d9d0c52) by Bradford Lamson-Scribner, May 2018,

[(Source)](https://github.com/bradford-hamilton/crystal-blockchain)



### JavaScript



[**Writing a Tiny Blockchain in JavaScript**](https://www.savjee.be/2017/07/Writing-tiny-blockchain-in-JavaScript/)

by Xavier Decuyper, July 2017



[**Node.js Blockchain Imlementation: BrewChain: Chain+WebSockets+HTTP Server**](http://www.darrenbeck.co.uk/blockchain/nodejs/nodejscrypto/) by Darren Beck, November 2017, [(Source)](https://github.com/dbbddb/BrewChain) -- Protecting the tea making ledger from unscrupulous colleagues



[**Build your own Blockchain in Javascript/Visualization of Blockchains**](https://github.com/nambrot/blockchain-in-js) by Nam Chu Hoai,  January 2018



### TypeScript



[**Naivecoin: a tutorial for building a cryptocurrency**](https://lhartikk.github.io) by Lauri Hartikka, [(Source)](https://github.com/lhartikk/naivecoin)



### Java



[**Creating Your First Blockchain with Java, Part 1**](https://medium.com/programmers-blockchain/create-simple-blockchain-java-tutorial-from-scratch-6eeed3cb03fa) by Kass, December 2017, [(Source)](https://github.com/CryptoKass/NoobChain-Tutorial-Part-1)



### Kotlin



[**Let's implement a cryptocurrency in Kotlin**](https://medium.com/@vasilyf/lets-implement-a-cryptocurrency-in-kotlin-part-1-blockchain-8704069f8580) by Vasily Fomin, July 2018,

[(Source)](https://github.com/VasilyFomin/kCoin)



### Go



**Building Blockchain in Go Series** by Ivan Kuznetsov, [(Source)](https://github.com/Jeiwan/blockchain_go)



- [**Part 1: Basic Prototype**](https://jeiwan.cc/posts/building-blockchain-in-go-part-1/), August 2017

- [**Part 2: Proof-of-Work**](https://jeiwan.cc/posts/building-blockchain-in-go-part-2/), August 2017

- [**Part 3: Persistence and CLI**](https://jeiwan.cc/posts/building-blockchain-in-go-part-3/), August 2017

- [**Part 4: Transactions 1**](https://jeiwan.cc/posts/building-blockchain-in-go-part-4/), September 2017

- [**Part 5: Addresses**](https://jeiwan.cc/posts/building-blockchain-in-go-part-5/), September 2017

- [**Part 6: Transactions 2**](https://jeiwan.cc/posts/building-blockchain-in-go-part-6/), September 2017

- [**Part 7: Network**](https://jeiwan.cc/posts/building-blockchain-in-go-part-7/), October 2017



Blockchain Series in Go by by Coral Health [(Source)](https://github.com/mycoralhealth/blockchain-tutorial)



- [**Code your own blockchain in less than 200 lines of Go!**](https://medium.com/@mycoralhealth/code-your-own-blockchain-in-less-than-200-lines-of-go-e296282bcffc) by Coral Health, January 2018

- [**Part 2: Networking — Code your own blockchain in less than 200 lines of Go!**](https://medium.com/@mycoralhealth/part-2-networking-code-your-own-blockchain-in-less-than-200-lines-of-go-17fe1dad46e1) by Coral Health, February 2018

- [**Code your own blockchain mining algorithm in Go!**](https://medium.com/@mycoralhealth/code-your-own-blockchain-mining-algorithm-in-go-82c6a71aba1f) by Coral Health, March 2018



### Talk Notes



- [**Blockchain! Blockchain! Blockchain! - Build Your Own Blockchains in JavaScript from Zero (Scratch)**](https://github.com/geraldb/talks/blob/master/blockchain.md) by Gerald Bauer, Vienna.js, September 2017

- [**Blockchain! Blockchain! Blockchain! - Build Your Own Blockchains in Ruby from Zero (Scratch)**](https://github.com/geraldb/talks/blob/master/blockchain_ruby.md) by Gerald Bauer, Vienna.rb, Dezember 2017

- [**Blockchain vs (Hyper) Ledger -- Inside (Hyper) Ledger Lite - Add Transactions One Block at a Time and Balance the Accounts (Books)**](https://github.com/geraldb/talks/blob/master/hyperledger.md) by Gerald Bauer, Hyperledger Vienna, March 2018

- [**Blockchain! Blockchain! Blockchain! - Build Your Own Blockchains in Go from Zero (Scratch)**](https://github.com/geraldb/talks/blob/master/blockchain_go.md) by Gerald Bauer, Vienna.go, April 2018



### More



See [**Build your own Blockchain / Cryptocurrency**](https://github.com/danistefanovic/build-your-own-x#build-your-own-blockchain--cryptocurrency) @ Build your own (insert technology here)



### Samples



#### Blockchain from Scratch - Ruby Version



```ruby

class Block



  attr_reader :timestamp

  attr_reader :data

  attr_reader :previous_hash

  attr_reader :hash



  def initialize(data, previous_hash)

    @timestamp     = Time.now

    @data          = data

    @previous_hash = previous_hash

    @hash          = calc_hash

  end



  def self.first( data="Genesis" )    # create genesis (big bang! first) block

    ## note: uses all zero for previous_hash ("0")

    Block.new( data, "0000000000000000000000000000000000000000000000000000000000000000" )

  end



  def self.next( previous, data="Transaction Data..." )

    Block.new( data, previous.hash )

  end



private



  def calc_hash

    sha = Digest::SHA256.new

    sha.update( @timestamp.to_s + @previous_hash + @data )

    sha.hexdigest

  end



end  # class Block



#####

## let's get started

##   build a blockchain a block at a time



b0 = Block.first( "Genesis" )

b1 = Block.next( b0, "Transaction Data..." )

b2 = Block.next( b1, "Transaction Data......" )

b3 = Block.next( b2, "More Transaction Data..." )



blockchain = [b0, b1, b2, b3]



pp blockchain



```



(Source: [`blockchain.rb`](blockchain.rb/blockchain.rb))



will pretty print (pp) something like:



```

[#,

 #,

 #,

 #]

```



Comments from the [reddit ruby posting](https://www.reddit.com/r/ruby/comments/70c30f/build_your_own_blockchain_in_20_lines_of_ruby/):



> Wait, so a blockchain is just a linked list?

>

>> No. A linked list is only required to have a reference to the previous element, a block must

>> have an identifier depending on the previous block's identifier, meaning that you cannot

>> replace a block without recomputing every single block that comes after.

>> In this implementation that happens as the previous digest is input in the calc_hash method.



**What about Proof of Work / Waste?**



Let's add a proof of work / waste to the blockchain. In the classic blockchain you have to compute a block hash that starts with leading zeros (`00`). The more leading zeros the harder (more difficult) to compute. Let's keep it easy to compute with two leading zeros (`00`), that is, 16^2 = 256 possibilites (^1,2). Three leading zeros (`000`) would be 16^3 = 4_096 possibilites and four zeros (`0000`) would be 16^4 = 65_536 and so on.



(^1): 16 possibilties because it's a hex or hexadecimal or base 16 number, that is, `0` `1` `2` `3` `4` `6` `7` `8` `9` `a` (10) `b` (11) `c` (12) `d` (13) `e` (14) `f` (15).



(^2): A random secure hash algorithm needs on average 256 tries (might be lets say 305 tries, for example, because it's NOT a perfect statistic distribution of possibilities).



Example:



```ruby

def compute_hash_with_proof_of_work( difficulty="00" )

  nonce = 0

  loop do

    hash = calc_hash_with_nonce( nonce )

    if hash.start_with?( difficulty )  

      return [nonce,hash]     ## bingo! proof of work if hash starts with leading zeros (00)

    else

      nonce += 1              ## keep trying (and trying and trying)

    end

  end

end



def calc_hash_with_nonce( nonce=0 )

  sha = Digest::SHA256.new

  sha.update( nonce.to_s + @timestamp.to_s + @previous_hash + @data )

  sha.hexdigest

end

```



(Source: [`blockchain_with_proof_of_work.rb`](blockchain.rb/blockchain_with_proof_of_work.rb))



Let's rerun the sample with the proof of work machinery added.

Now the sample will pretty print (pp) something like:



```

[#,

 #,

 #,

 #]

```



See the difference? All hashes now start with leading zeros (`00`) and the nonce is the random "lucky number"

that makes it happen. That's the magic behind the proof of work.



##### Blockchain from Scratch - JavaScript Version



```js

class Block {



  constructor(data, previousHash) {

    this.timestamp    = new Date()

    this.data         = data

    this.previousHash = previousHash

    this.hash         = this.calcHash()

  }



  calcHash() {

    var sha = SHA256.create()

    sha.update( this.timestamp.toString() + this.previousHash + this.data )

    return sha.hex()

  }



  static first( data="Genesis" ) {    // create genesis (big bang! first) block

    // uses all-zero previousHash

    return new Block( data, "0000000000000000000000000000000000000000000000000000000000000000" )

  }



  static next( previous, data="Transaction Data..." ) {

    return new Block( data, previous.hash )

  }

}



//////

// let's get started

//   build a blockchain a block at a time



b0 = Block.first( "Genesis" )

b1 = Block.next( b0, "Transaction Data..." )

b2 = Block.next( b1, "Transaction Data......" )

b3 = Block.next( b2, "More Transaction Data..." )



blockchain = [b0, b1, b2, b3]



console.log( blockchain )

```



(Source: [`blockchain.js`](blockchain.js/blockchain.js))



will log something like:



```

[ Block {

     timestamp    : 1637-09-18 08:25:54,

     data         : 'Genesis',

     previousHash : '0000000000000000000000000000000000000000000000000000000000000000',

     hash         : 'c396de4c03ddb5275661982adc75ce5fc5905d2a2457d1266c74436c1f3c50f1' },

   Block {

     timestamp    : 1637-09-18 08:35:54,

     data         : 'Transaction Data...',

     previousHash : 'c396de4c03ddb5275661982adc75ce5fc5905d2a2457d1266c74436c1f3c50f1',

     hash         : '493131e09c069645c82795c96e4715cea0f5558be514b5096d853a5b9899154a' },

   Block {

     timestamp    : 1637-09-18 08:45:54,

     data         : 'Transaction Data......',

     previousHash : '493131e09c069645c82795c96e4715cea0f5558be514b5096d853a5b9899154a',

     hash         : '97aa3cb5052615d60ff8e6b41bef606562588c4874f011970ac2f218e2f0f4a8' },

   Block {

     timestamp    : 1637-09-18 08:55:54,

     data         : 'More Transaction Data...',

     previousHash : '97aa3cb5052615d60ff8e6b41bef606562588c4874f011970ac2f218e2f0f4a8',

     hash         : 'e10e020f832e46c2b60e1c3c0412bd370b2fde5f0f782c16eb87d0313ea0d3a3' } ]

```



## Blockchain Articles



[**Reflections on the Blockchain**](http://rufuspollock.com/2016/07/02/reflections-on-the-blockchain) by Rufus Pollock (Open Knowledge Foundation), July 2016 --

_The DAO: Code is not Law – and It’s Dangerous to Think So ++

The Internet changed the world - surely the Blockchain will too? ++

Gold-rush or Internet-rush? ++

Governance Matters in Bitcoin ++

The Myth of a Costless, Ownerless Network ++

Lessons from History_



[**On the Dangers of a Blockchain Monoculture**](https://tonyarcieri.com/on-the-dangers-of-a-blockchain-monoculture) by Tony Arcieri, January 2016 --

_The Bitcoin blockchain: the world's worst database ++

Next-generation protocols ++

Decentralized ledger protocols ++

Bitcoin-NG ++

Blockchain! Blockchain! Blockchain! ++

The great decentralized database in the sky_



[**I Don’t Believe in Blockchain**](https://www.tbray.org/ongoing/When/201x/2017/05/13/Not-Believing-in-Blockchain) by Tim Bray, May 2017



[**Minimum Viable Blockchain**](https://www.igvita.com/2014/05/05/minimum-viable-block-chain/) by Ilya Grigorik, May 2014 --

_Securing transactions with triple-entry bookkeeping ++

Securing transactions with PKI ++

Balance = Σ(receipts) ++

Multi-party transfers & verification ++

Double-spending and distributed consensus -

 Requirements for a distributed consensus network;

 Protecting the network from Sybil attacks;

Proof-of-work as a participation requirement ++

Building the minimum viable blockchain -

 Adding "blocks" & transaction fee incentives;

 Racing to claim the transaction fees;

 Resolving chain conflicts;

 Blocks are never final ++

Properties of the (minimum viable) blockchain_



[**Blockchains by analogies and applications: How blockchain compares to Git, Raft, and other technologies.**](https://www.oreilly.com/ideas/blockchains-by-analogies-and-applications)

by Kieren James-Lubin, January 2016 --

_Blockchains are databases ++

Understanding transactions ++

Persistent, replicated databases (related technology: Git) ++

Peer-to-peer networks (related technology: BitTorrent) ++

Distributed consensus (related technology: distributed databases, Raft) ++

Minting new coins (mining) ++

Embedded identities (related technology: TLS) ++

Smart contracts: Like SQL expressions & triggers ++

What can we really do with blockchains?_



## Blockchain Books



[**Attack of the 50 Foot Blockchain: Bitcoin, Blockchain, Ethereum & Smart Contracts**](https://davidgerard.co.uk/blockchain/table-of-contents/) by David Gerard, London, 2017 --

_What is a bitcoin? ++

The Bitcoin ideology ++

The incredible promises of Bitcoin! ++

Early Bitcoin: the rise to the first bubble ++

How Bitcoin mining centralised ++

Who is Satoshi Nakamoto? ++

Spending bitcoins in 2017 ++

Trading bitcoins in 2017: the second crypto bubble ++

Altcoins ++

Smart contracts, stupid humans ++

Business bafflegab, but on the Blockchain ++

Case study: Why you can’t put the music industry on a blockchain_



[**Mastering Bitcoin - Programming the Open Blockchain**](https://github.com/bitcoinbook/bitcoinbook/blob/second_edition/ch09.asciidoc) 2nd Edition,

by Andreas M. Antonopoulos, 2017 - FREE (Online Source Version) --

_What Is Bitcoin? ++

How Bitcoin Works ++

Bitcoin Core: The Reference Implementation ++

Keys, Addresses ++

Wallets ++

Transactions ++

Advanced Transactions and Scripting ++

The Bitcoin Network ++

The Blockchain ++

Mining and Consensus ++

Bitcoin Security ++

Blockchain Applications_



---



![](i/trolly-ponzi.png)



**BEWARE: Bitcoin is a gigantic ponzi scheme¹.

To the moon!? The new gold standard!? 

Do NOT "invest" trying to get-rich-quick HODLing. 

Why not? The bitcoin code is archaic and out-of-date.

Burn, baby, burn! Proof-of-work / waste is a global

energy environmental disaster

using 300 kW/h per bitcoin transaction (!) that's about 179 kilograms of CO₂ emissions².

Programmable money (or the internet of value) 

for all future generations with (bitcoin) script

without loops and jumps (gotos) and all "stateless"!? LOL.**



¹: (Source: [Best of Bitcoin Maximalist - Scammers, Morons, Clowns, Shills & BagHODLers - Inside The New New Crypto Ponzi Economics](https://bitsblocks.github.io/bitcoin-maximalist))



²: Assuming let's say 0.596 kilograms of CO₂ per kW/h 

(that's the energy efficiency in Germany) that's 

about 179 kilograms of CO₂ per bitcoin transaction (300 kW/h × 0.596 kg). For more insights see the [Bitcoin Energy Consumption Index](https://digiconomist.net/bitcoin-energy-consumption).



---



[**Programming Bitcoin from Scratch**](https://github.com/jimmysong/programmingbitcoin) by Jimmy Song, 2019 - FREE (Online Source Version) -- _[Chapter 6 - Script](https://github.com/jimmysong/programmingbitcoin/blob/master/ch06.asciidoc) - How Script Works • Example Operations • Parsing the Script Fields • Combining the Script Fields • Standard Scripts • p2pk • Problems with p2pk • Solving the Problems with p2pkh • Scripts Can Be Arbitrarily Constructed • Conclusion ++_

_[Chapter 8 - Pay-to-Script Hash](https://github.com/jimmysong/programmingbitcoin/blob/master/ch08.asciidoc) - Bare Multisig • Coding OP_CHECKMULTISIG • Problems with Bare Multisig • Pay-to-Script-Hash (p2sh) • Coding p2sh • Conclusion ++_

_[Chapter 13 - Segregated Witness](https://github.com/jimmysong/programmingbitcoin/blob/master/ch13.asciidoc) - Pay-to-Witness-Pubkey-Hash (p2wpkh) • p2wpkh Transactions • p2sh-p2wpkh • Coding p2wpkh and p2sh-p2wpkh • Pay-to-Witness-Script-Hash (p2wsh) • p2sh-p2wsh • Coding p2wsh and p2sh-p2wsh • Other Improvements • Conclusion_

  



[**Programming Bitcoin Script Transaction (Crypto) Contracts Step-by-Step ( Beta / Rough Draft )**](https://github.com/openblockchains/programming-bitcoin-script)

by Gerald Bauer et al, 2019 - FREE (Online Version) --

_Let's start with building your own bitcoin stack machine from zero / scratch and let's run your own bitcoin ops (operations)..._



[**Programming Blockchains in Ruby from Scratch Step-by-Step Starting w/ Crypto Hashes... ( Beta / Rough Draft )**](https://github.com/yukimotopress/programming-blockchains-step-by-step)

by Gerald Bauer et al, 2018 - FREE (Online Version) --

_(Crypto) Hash ++

(Crypto) Block ++

(Crypto) Block with Proof-of-Work ++

Blockchain! Blockchain! Blockchain! ++

Blockchain Broken? ++

Timestamping ++

Mining, Mining, Mining - What's Your Hash Rate? ++

Bitcoin, Bitcoin, Bitcoin ++

(Crypto) Block with Transactions (Tx)_



[**Mastering Ethereum - Building Contract Services and Decentralized Apps on the Blockchain**](https://github.com/ethereumbook/ethereumbook) -

by Andreas M. Antonopoulos, Gavin Wood, 2018 - FREE (Online Source Version)

_What is Ethereum ++

Introduction ++

Ethereum Clients ++

Ethereum Testnets ++

Keys and Addresses ++

Wallets	++

Transactions ++

Contract Services ++

Tokens ++

Oracles ++

Accounting & Gas ++

EVM (Ethereum Virtual Machine) ++ 	

Consensus ++		

DevP2P (Peer-To-Peer) Protocol ++

Dev Tools and Frameworks ++

Decentralized Apps ++

Ethereum Standards (EIPs/ERCs)_



[**Building Decentralized Apps on the Ethereum Blockchain**](https://www.manning.com/books/building-ethereum-dapps) by Roberto Infante, 2018 - FREE chapter 1 --

_Understanding decentralized applications ++

The Ethereum blockchain ++

Building contract services in (JavaScript-like) Solidity ++

Running contract services on the Ethereum blockchain ++

Developing Ethereum Decentralized apps with Truffle ++

Best design and security practice_



[**Programming Crypto Blockchain Contracts Step-by-Step Book / Guide ( Beta / Rough Draft )**](https://github.com/openblockchains/programming-cryptocontracts) by Gerald Bauer et al, 2019 - FREE (Online Version) --

_Let's Start with Ponzi & Pyramid Schemes. Run Your Own Lotteries, Gambling Casinos and more on the Blockchain World Computer..._



[**Programming Cryptocurrencies and Blockchains in Ruby ( Beta / Rough Draft )**](http://yukimotopress.github.io/blockchains)

by Gerald Bauer et al, 2018 - FREE (Online Version) @ Yuki & Moto Press Bookshelf --

_Digital $$$ Alchemy - What's a Blockchain? -

How-To Turn Digital Bits Into $$$ or €€€? •

Decentralize Payments. Decentralize Transactions. Decentralize Blockchains. •

The Proof of the Pudding is ... The Bitcoin (BTC) Blockchain(s)

++

Building Blockchains from Scratch -

A Blockchain in Ruby in 20 Lines! A Blockchain is a Data Structure  •

What about Proof-of-Work? What about Consensus?   •

Find the Lucky Number - Nonce == Number Used Once

++

Adding Transactions -

The World's Worst Database - Bitcoin Blockchain Mining  •

Tulips on the Blockchain! Adding Transactions

++

Blockchain Lite -

Basic Blocks  •

Proof-of-Work Blocks  •

Transactions

++

Merkle Tree -

Build Your Own Crypto Hash Trees; Grow Your Own Money on Trees  •

What's a Merkle Tree?   •

Transactions

++

Central Bank -

Run Your Own Federated Central Bank Nodes on the Blockchain Peer-to-Peer over HTTP  •

Inside Mining - Printing Cryptos, Cryptos, Cryptos on the Blockchain

++

Awesome Crypto

++

Case Studies - Dutch Gulden  • Shilling  • CryptoKitties (and CryptoCopycats)_



[**Blockchain for Dummies, IBM Limited Edition**](https://www.ibm.com/blockchain/what-is-blockchain.html) by Manav Gupta, 2017 - FREE (Digital Download w/ Email) --

_Grasping Blockchain Fundamentals ++

Taking a Look at How Blockchain Works ++

Propelling Business with Blockchains ++

Blockchain in Action: Use Cases ++

Hyperledger, a Linux Foundation Project ++

Ten Steps to Your First Blockchain application_



[**Get Rich Quick "Business Blockchain" Bible - The Secrets of Free Easy Money**](https://github.com/bitsblocks/get-rich-quick-bible), 2018 - FREE --

_Step 1: Sell hot air. How? ++

Step 2: Pump up your tokens. How? ++

Step 3: Revolutionize the World. How?_



[**Best of Bitcoin Maximalist - Scammers, Morons, Clowns, Shills & BagHODLers - Inside The New New Crypto Ponzi Economics**](https://github.com/bitsblocks/bitcoin-maximalist) by Trolly McTrollface, et al, 2018 - FREE 



[**Crypto Facts - Decentralize Payments - Efficient, Low Cost, Fair, Clean - True or False?**](https://github.com/bitsblocks/crypto-facts) by Nouriel Roubini, David Gerard, et al, 2018 - FREE 



[**Crypto is the Mother of All Scams and (Now Busted) Bubbles - While Blockchain Is The Most Over-Hyped Technology Ever, No Better than a Spreadsheet/Database**](https://github.com/bitsblocks/crypto-bubbles) by Nouriel Roubini, 2018 - FREE 



[**IslandCoin White Paper - A Pen and Paper Cash System - How to Run a Blockchain on a Deserted Island**](https://github.com/bitsblocks/islandcoin-whitepaper)

by Tal Kol -- 

_Motivation ++

Consensus ++

Transaction and Block Specification -

Transaction format •

Block format •

Genesis block ++

References_



## Blockchain (Lite) Crypto Hash Libraries



[Ruby](#ruby) •

[JavaScript](#javascript)



### Ruby



**blockchain.lite** (github: [openblockchains/blockchain.lite.rb](https://github.com/openblockchains/blockchain.lite.rb),

gem: [blockchain-lite](https://rubygems.org/gems/blockchain-lite)) -

build your own blockchain with crypto hashes -

revolutionize the world with blockchains, blockchains, blockchains one block at a time



```ruby

require 'blockchain-lite'



b0 = Block.first( "Genesis" )

b1 = Block.next( b0, "Transaction Data..." )

b2 = Block.next( b1, "Transaction Data......" )

b3 = Block.next( b2, "More Transaction Data..." )



blockchain = [b0, b1, b2, b3]



pp blockchain   

```



will pretty print (pp) something like:



```

[#,

 #,

  ...

```



### JavaScript



**blockchain.lite** (github: [openblockchains/blockchain.lite.js](https://github.com/openblockchains/blockchain.lite.js),

npm: [blockchain-lite](https://www.npmjs.com/package/blockchain-lite)) -

build your own blockchain with crypto hashes -

revolutionize the world with blockchains, blockchains, blockchains one block at a time



```js

const Blocks = require( "blockchain-lite" )



// use basic block

let Block = Blocks.basic



let b0 = Block.first( 'Genesis' )

let b1 = Block.next( b0, 'Transaction Data...' )

let b2 = Block.next( b1, 'Transaction Data......' )

let b3 = Block.next( b2, 'More Transaction Data...' )



let blockchain = [b0, b1, b2, b3]



console.log( blockchain )

```



will log something like:



```

[ Block {

    timestamp:     2017-09-25 17:03:38,

    data:         'Genesis',

    previousHash: '0000000000000000000000000000000000000000000000000000000000000000',

    hash:         '08f4fa71628c5bc6b430228738bc8c41afaf508ece0b1cf9c9cac53d02e11829' },

  Block {

    timestamp:     2017-09-25 17:13:38,

    data:         'Transaction Data...',

    previousHash: '08f4fa71628c5bc6b430228738bc8c41afaf508ece0b1cf9c9cac53d02e11829',

    hash:         '740a4aeb3441484c96d1e7f63d31b716220ccee3b6fe94547cae2afbb6010626' },

  Block {

    timestamp:     2017-09-25 17:23:38,

    data:         'Transaction Data......',

    previousHash: '740a4aeb3441484c96d1e7f63d31b716220ccee3b6fe94547cae2afbb6010626',

    hash:         '28b6892a069e2ff7f1c3128ab495d7cd9b9b1636a51a7f69db93a14b1ee6b1a7' },

  Block {

    timestamp:     2017-09-25 17:33:38,

    data:         'More Transaction Data...',

    previousHash: '28b6892a069e2ff7f1c3128ab495d7cd9b9b1636a51a7f69db93a14b1ee6b1a7',

    hash:         '4cc0329b2c0cb32e0451fa3179bd944d4cd0fcf410939172f979e9fd2aa9f5f3' } ]

```



## Git, Git, Git - The Stupid Content Tracker with Crypto Hashes



_Everything is local. Distributed is the new centralized._



![](i/xkcd1597.png)



### Quotes - Blockchains and Git



> Yep, that's the joke. Nobody has been able to explain to me how the "blockchain" buzzword is significantly different to "git repo".

> -- [Yaakov](https://twitter.com/yaakov_h/status/902659507255312384)

>

> But if you said "let's build a currency where all transactions are stored in a git repo"

> you wouldn't be taken seriously for even 24 hrs.

> -- [Yaakov](https://twitter.com/yaakov_h/status/902659847224664064)



> Soon explaining git like "a git repo is like a blockchain with commits instead of blocks".

> -- [Nicolás Berger](https://twitter.com/nicoberger/status/901776907418697729)

>

> "A local branch is like a state channel. It can be pushed and merged into the master blockchain at any moment."

> -- [Nicolás Berger](https://twitter.com/nicoberger/status/901777571456614400)



> The #Blockchain has changed the world. Here I make the argument that the #Blockchain is just like #git.

> -- [Jackson Kelley](https://twitter.com/sjkelleyjr/status/901464041163341824)



> `git merge [-m REF] [-g BLOB] --push`

>  Merge and push all signed commits to the blockchain.

> -- [Git Commands](https://twitter.com/git_commands/status/935574015015612416)



### Books



[**Learn Enough Git to Be Dangerous**](https://learnenough.com/git-tutorial) by Michael Hartl - FREE (Online Version) --

_Getting started ++

Backing up and sharing ++

Intermediate workflow ++

Collaborating ++

Conclusion ++

Advanced setup_



[**Pro Git**](https://git-scm.com/book) by Scott Chacon and Ben Straub, 2nd Edition, 2014 - FREE (Online Version) --

_Getting Started ++

Git Basics ++

Git Branching ++

Git on the Server ++

Distributed Git ++

GitHub ++

Git Tools ++

Customizing Git ++

Git and Other Systems ++

Git Internals ++

A1: Git in Other Environments ++

A2: Embedding Git in your Applications ++

A3: Git Commands_



> Git gets easier once you get the basic idea that branches are homeomorphic endofunctors

> mapping submanifolds of a Hilbert space.

> -- Anonymous



### Open Distributed Databases on Git



[**football.db**](https://github.com/openfootball) - open public domain football datasets (incl. clubs, national teams, leagues, match schedules, etc.)



[**world.db**](https://github.com/openmundi) - open public domain world (country) datasets



[**beer.db**](https://github.com/openbeer) - open public domain beer & brewery datasets



> Add a beer transaction to the #blockchain on #git and win a free Wiener Lager beer! Cheers. Prost.

> -- [Gerald Bauer @ Austria Codes](https://twitter.com/austriacodes/status/907240018435088384)



### Open Distributed (Hyper) Ledger Books on Git



[**Shilling (or Schilling)**](https://github.com/bitshilling/bitshilling) - Shilling on the Blockchain! - Rock-Solid Alpine Dollar from Austria



[**Tulips**](https://github.com/openblockchains/tulips) - Tulips on the Blockchain! - Learn by Example from the Real World (Anno 1637) - Buy! Sell! Hold! Enjoy the Beauty of Admiral of Admirals, Semper Augustus, and More



## Classic Tulip Mania



_A period in the Dutch Golden Age during which contract prices for bulbs of the recently introduced tulip reached extraordinarily high levels and then dramatically collapsed in February 1637._



![](i/tulipmania-ii.png)



### Quotes - Blockchains are the next Internets / Tulips



> People who compare digital tokens to tulips are essentially saying digital tokens are a bubble backed

> by nothing but pure hype and speculation.

>

> What they fail to understand is that tulips come from dirt, not a blockchain.

>

> And as we all know, blockchain is possibly the best technological innovation since the internet.

> It will have a tremendous impact on global business and society in general.

> -- [TulipToken](http://tuliptoken.com)



### Books



**Tulipomania: The Story of the World's Most Coveted Flower & the Extraordinary Passions It Aroused** by Mike Dash, 2001 --

_A Mania for Tulips ++

The Valley of Tien Shan ++

Within the Abode of Bliss ++

Stranger from the East ++

Clusius ++

Leiden ++

An Adornment to the Cleavage ++

The Tulip in the Mirror ++

Florists ++

Boom ++

At the Sign of the Golden Grape ++

The Orphans of Wouter Winkel ++

Bust ++

Goddess of Whores ++

At the Court of the Tulip King ++

Late Flowering_



**Tulipmania: Money, Honor, and Knowledge in the Dutch Golden Age** by Anne Goldgar, 2007  --

_Something Strange ++

Art & Flowers ++

Bloemisten ++

Grieving Money ++

Bad Faith ++

Cabbage Fever ++

Glossary ++

A Note on Money_



![](i/tulipmania.png)



## Breaking News: CryptoKitties (Yes, Cute Little Cartoon Cats) on the Blockchain!



Collectible. Breedable. Adorable.



Collect and breed digital cats. Start meow. Buy! Sell! Hold!



Learn more @ [cryptokitties.co](https://cryptokitties.co)



![](i/cryptokitties-top10-sales.png)



Latest (and Greatest) Investment Opportunity!



> Blockchain has unlocked the magic of digital scarcity, and combining that with the power of

> making the digital goods persistent gives them a potential value that is only limited by how much

> prestige a wealthy person might place on ownership of the item.

>

> -- [Justin Poirier](https://twitter.com/tokenizedcap/status/938460753589424128)‏



> All I want for Christmas is a CryptoKitty.

>

> -- [Kayla Williams](https://twitter.com/kaylaw/status/938590748655550464)



> I got a fever. And the only prescription is more CryptoKitties.

>

> -- [Eduardo Salazar](https://twitter.com/ceduardosalazar/status/938558630663634944)



> My Gen 7 CryptoKitty #104375. The Future is Meow.

>

> -- [Anshul Dhawan](https://twitter.com/TheAnshulDhawan/status/938551642202324993)



![](i/cryptokitties-genes01.png)



> - Fabulous Persian Spock Gerbil Gold Cottoncandy - Extremely rare gen 5 swift virgin | 2.9 ETH

> - Rarity: 0.00264% Gen 5 JAGUAR FABULOUS GOLD DALI!! VIRGIN!

> - Rarity: 0.0015% Princess Bubblegum is now for sale! Gen 12 | Brisk | Virgin | Chartreux | Bubblegum | Otaku | Emeraldgreen | Saycheese | Mauveover | Spock - Starts ETH 20/Ends ETH 10

> - Gold ducat, Gen 5, Virgin, Swift. Very cheap

> - Cheap Gen 1 cute kittie with rare genes! Only 0.125 ETH

> - UNIQUE Virgin Peach Googly Gold Mauveover gen:2 cooldown:1 0.87992% RARE

> - SUPER CHEAP: Gerbil, Ragdoll, Scarlet, Chestnut, Cotton Candy!!! 0.02 ETH (~$14)

> - I'm giving away a Gen 1 FAST Gold for free...

>

> -- [CrypoKittiesMarket](https://www.reddit.com/r/CryptoKittiesMarket)



### Awesome CryptoKitties (and CryptoCopycats)



![](i/cryptokitties-modernart-paintings.png)



A collection about Awesome CryptoKitties (Yes, Cute Little Cartoon Cats) on the Blockchain! and CryptoCopycats - digital collectibles secured on a distributed public databases w/ crypto hashes. Are CryptoPuppies the new CryptoKitties? Learn by Example from the Real World (Anno 2017) - Buy! Sell! Hodl!



More @ [cryptocopycats/awesome-cryptokitties](https://github.com/cryptocopycats/awesome-cryptokitties)



![](i/cryptokitties-modernart-paintings-iii.png)



## Events, Meetups, Orgs



_Revolutionize the world one country at a time. Blockchainers of the world, unite!_



- [**Blockchain Austria • Blockkette Österreich**](https://github.com/austriacodes/blockchain-austria) -- distributed centralized page for blockchain meetups & orgs in Austria (Central Europe)



## Awesome Awesomeness



_A curated list of awesome lists._



- [**Blockchain Stuff**](https://github.com/Xel/Blockchain-stuff) -- a curated list of blockchain and general cryptocurrency resources

- [**Awesome Blockchain**](https://github.com/igorbarinov/awesome-blockchain) by Igor Barinov et al -- a curated list of the bitcoin blockchain services

- [**Awesome Blockchain**](https://github.com/imbaniac/awesome-blockchain) by Tim Reznich et al -- a curated list of blockchain services and exchanges

- [**Awesome Blockchain**](https://github.com/istinspring/awesome-blockchain) by `istinspring` et al -- a curated list of awesome projects and services based on blockchain technology

- [**Awesome Coins**](https://github.com/kennethreitz/awesome-coins) by Kenneth Reitz et al -- a guide to crypto-currencies and their algos

- [**Awesome CryptoKitties (and CryptoCopycats)**](https://github.com/openblockchains/awesome-cryptokitties) by Gerald Bauer et al -- a curated list about the awesome crypto kitties and copycats

- [**Awesome Git**](https://github.com/dictcp/awesome-git) by Dick Tang et al -- a curated list of amazingly awesome Git tools, resources and shiny things

- [**Awesome**](https://github.com/sindresorhus/awesome) by Sindre Sorhus et al -- a curated list of awesome lists



## Meta



**License**



![](https://publicdomainworks.github.io/buttons/zero88x31.png)



The awesome list is dedicated to the public domain. Use it as you please with no restrictions whatsoever.