Wasp is a node software developed by IOTA Foundation to run the IOTA Smart Contract Protocol (ISC, ISCP in short) on top of the IOTA Tangle. Please find here a high level introduction into ISC.
A smart contract is a distributed software agent which keeps its state in the immutable ledger. The state is an append-only structure which evolves with each request to the smart contract.
State of the smart contract, including tokens deposited into it and the attached arbitrary data, is anchored in the Value Tangle, the UTXO ledger. So, the IOTA ledger ensures state is immutable.
Each SC is run by the distributed and leaderless committee of Wasp nodes. The main purpose of the committee is to ensure consistent transition from the previous state to the next, according to the attached program. The program itself is immutably stored with the smart contract too.
So, IOTA smart contracts are run by the network of Wasp nodes, all connected to the Tangle.
The articles below explains how to run a Wasp node on the Pollen network, also concepts and architecture of ISCP and Wasp. We describe it using several PoC smart contracts as an example.
Disclaimer. Wasp node and articles is a work in progress, and most likely will always be. The software presented in this repo is not ready for use in commercial settings or whenever processing of critical data is involved.