Blockchain App Development

with JS and Hyperledger Sawtooth

Zac Delventhal

github.com/delventhalz

@delventhalz

Satoshi invents the "block chain" in 2008
Distributed consensus enforces trust
Potentially replaces any central authority

https://www.youtube.com/watch?v=Zc4UIpcgkR8

General purpose, modular
Focused on consortiums
Features a novel consensus model: PoET

What is a Blockchain Application?

Blockchain is the platform
Consumes and writes to blockchain state
The blockchain is the "server"

https://techcrunch.com/2017/05/10/pokitdok-teams-with-intel-on-healthcare-blockchain-solution/

Signing

Private Key

Public Key

Message

Signature

Public Key

Signature

Message

(secp256k1)

Transaction payloads are opaque to Sawtooth
Pluggable processors handle this data
Can query and modify blockchain state
One per use case (usually)

Transaction Processors

State

Validator

Client

Processor

Transactions

and Batches

TransactionHeader

string batcher_pubkey
repeated string dependencies
string family_name
string family_version
repeated string inputs
string nonce
repeated string outputs
string payload_encoding
string payload_sha512
string signer_pubkey

bytes header
string header_signature
bytes payload

bytes header
string header_signature
repeated Transaction transactions

string signer_pubkey
repeated string transaction_ids

repeated Batch batches

Transaction

Batch

BatchHeader

BatchList

JavaScript SDK

Demo

Take Aways?

Blockchains are neat (or at least useful)
Potentially huge market in the next few years
They are already easy to develop for, and getting easier