bitcoinscri.pt

About Bitcoin Scripts

Scripting languages date back from thousands of years ago. Mathematic formulae are an example of scripting language.
Bitcoin scripts use a specialized scripting language to write secure smart contracts and complex transactions.

Prepare your own Bitcoin Address

A Smart Contract is initiated by computing a Bitcoin P2SH address. P2SH stands for Pay-to-Script-Hash, meaning the Contract Script is hashed into a unique address that will serve as a vault for the funds sent to it.

Spend from the P2SH Address

To spend the funds previously sent to the Smart Contract P2SH address, you will need to provide the original redeem Script as well as one or more private keys required by the Script.

Timelock

A Script may enforce time conditions that must be met to unlock the funds held at the P2SH address. If you want to spend from the P2SH address of such Script, you may have to wait until the time lock expires.

A Stack-based Scripting System

Bitcoin uses a scripting system for complex transactions. Forth-like, Script is stack-based: instructions are 1-byte opcodes processed from left to right to be pushed on top of the stack sequentially, left-most first. All values are variable length byte arrays. Script is not Turing-complete, with no loops, for optimal security.

A portfolio of scripts

There are many use cases for Bitcoin scripts.
Stay tuned: you'll find here links to some more demos.

Time Locked Address

This very simple script sets an expiry date and public key that must be matched to unlock the funds. The funds cannot move from the time locked address until the set expiry date and time. After the expiry, a single private key is required.

Time Locked 2FA

The Script requires two keys before the set expiry date and only one key after the expiry date. If one of the keys is yours and the other belongs to a 2FA (2FA stands for two-factor authentication) service provider, the funds can be accessed after the expiry date even if the 2FA service provider has disappeared.

Contract Oracle

An external data source can be linked to a P2SH address with a certain value set in the script. The script requires two keys to unlock the funds, one key held by the beneficiary, the other key held by a trusted Oracle whose job is to validate that the value conditions are met.

Hashed Timelocked Contract

Hashed Timelock Contract (HTLC) as proposed in the lightning.network paper. The receiver can include a 0 or 1 in the scriptSig to choose to enter through if or else branch.

Lightning Network: a compelling use case for Bitcoin scripts

The Lightning Network white paper ( draft version 0.5.9.1 dated November 20, 2015) describes a decentralized network for scalable, efficient payment channels. Transactions are sent over this routing network of micropayment channels whose transfer of value occurs off-blockchain. Bitcoin scripts enable time locked and hash locked transactions so that the payment protocol between users, via any number of Lightning Network hubs, remains trustless. This white paper by Joseph Poon and Thaddeus Dryja is probably the most important contribution since the invention of Bitcoin.

Download White Paper

Reach out

I have developped this website to help you write smart contracts using Bitcoin scripts. If you want to suggest a script be added to this demo portfolio, please let me know.

Pierre Noizat

Script Writer & Coder

Bitcoin Scripts and Smart Contracts. Explained.

About Bitcoin Scripts

A Stack-based Scripting System

A portfolio of scripts

Lightning Network: a compelling use case for Bitcoin scripts

Reach out