What do you all think about writing a blockchain in Elixir? Being a functional language and having OTP in our arsenal, it seems it would be easier to get a block chain up-and-running quickly. We even have some good starting points for the consensus algorithm and hash trees:

Blockchain resources

Elixir community effort

• exchain/exchain on GitHub
• robinmonjo/coincoin

Background

Videos

• DEVCON1: Understanding the Ethereum Blockchain Protocol - Vitalik Buterin

Topical

General

• “Explainers” on core concepts like blockchains and smart contracts

Bitcoin

• Bitcoin Block Chain developer reference

Ethereum

• Ethereum Design Rationale
• Ethereum Virtual Machine and Execution Environment Overview
• Ethereum Platform Review Opportunities and Challenges for Private and Consortium Blockchains
  • Executive Summary

Books

• Princeton Bitcoin Book
• Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World by Don Tapscott et al.
• The Science of the Blockchain by Roger Wattenhofer
• Mastering Bitcoin: Unlocking Digital Cryptocurrencies by Andreas M. Antonopoulos

White Papers

• Ethereum
• Hyperledger

Benchmarks

These projects are in active (rapid!) development and in a variety of languages.

• Ethereum
  • Ethcore Parity (Rust)
  • go-ethereum/Geth (Go)
  • webthree-umbrella (C++)
  • ethereumj (Java)
  • pyethereum (Python)
  • ethereum-client-haskell (Haskell) – looks stagnant
  • ruby-ethereum (Ruby)
• Hyperledger
  • Fabric (Go)
  • Sawtooth (Python)
  • Juno (Haskell) – Smart Contracts Running on a BFT Hardened Raft
• Stellar
  • stellar-core (C++)

Academic Papers

Specific implementations

• Bitcoin: A Peer-to-Peer Electronic Cash System
• Ethereum Yellow Paper – formal specification

Meta-analysis

• The Quest for Scalable Blockchain Fabric: Proof-of-Work vs. BFT Replication
• Hiding Transaction Amounts and Balances in Bitcoin (zero knowledge proofs)
• Misbehavior in Bitcoin: A Study of Double-Spending and Accountability (double-spending attack)

Distributed consensus

• Tangaroa: a Byzantine Fault Tolerant Raft
• Practical Byzantine Fault Tolerance (PBFT)
• Building Replicated Systems for Performance (“Adam”)
• All about Eve: Execute-Verify Replication for Multi-Core Servers (extended version)
• The Stellar Consensus Protocol: A Federated Model for Internet-level Consensus
• Raft Refloated: Do We Have Consensus?
• Non-determinism in Byzantine Fault-Tolerant Replication
• CheapBFT: Resource-efficient Byzantine Fault Tolerance
• Reaching Agreement in the Presence of Faults

Proofs of “X”

Various methods of using blockchain technologies to prove something in a way that is cryptographically verifiable.

FOR CRYPTOCURRENCY

• Proof of Work (PoW)
• Proof of Stake (PoS)

OTHER PROOFS

• Proof of Elapsed Time (PoET)
• Proof of Existence (or Publication)
• Proof of Ownership
• Proof of Integrity
• Proof of Agreement
• Proof of Receipt

Blockchain components

Distributed consensus algorithms

A fundamental problem in distributed computing and multi-agent systems is to achieve overall system reliability in the presence of a number of faulty processes. This often requires processes to agree on some data value that is needed during computation. Examples of applications of consensus include whether to commit a transaction to a database, agreeing on the identity of a leader, state machine replication, and atomic broadcasts. (Wikipedia)

• raftex - Raft consensus
• expaxos - Paxos consensus
• rafute - Another implementation of Raft
• dike - Paxos implementation in Erlang

Merkle (hash) trees

A hash tree or Merkle tree is a tree in which every non-leaf node is labelled with the hash of the labels or values (in case of leaves) of its child nodes. Hash trees are useful because they allow efficient and secure verification of the contents of large data structures. Hash trees are a generalization of hash lists and hash chains. (Wikipedia)

Elixir

• merkle_tree — blog post
• elixir-merkle

Erlang

• merklet
• Hash trees - Riak implementation
  • hashtree.erl
  • hashtree_tree.erl

Cryptography

Elixir

• elixir-rsa - Erlang public_key cryptography wrapper
• elixir-ecc - elliptic curve cryptography
• elixir-mcrypt - NIF wrapper around libmcrypt
• cryptex - library for encrypting/decrypting, signing/verifying data

Erlang

• :crypto

Keywords: state machine replication, distributed cryptographic ledger, transaction log