# tari_engine_types
[](https://crates.io/crates/tari_engine_types)
[](https://docs.rs/tari_engine_types)
Shared data types for the Tari template engine. This crate defines the core domain
model — substates, vaults, buckets, resources, proofs, transaction receipts, and
supporting cryptographic helpers — used across the engine, validator nodes, and
test tooling.
## Key types
| `Substate` / `SubstateId` | Versioned on-chain state and its identifier |
| `ComponentHeader` | Metadata attached to a deployed component (template address, access rules, owner rule) |
| `Resource` | Fungible or non-fungible resource definition |
| `Vault` | On-chain container that holds a resource |
| `Bucket` | Ephemeral resource container used during transaction execution |
| `Proof` | Proof used for authorisation checks |
| `TransactionReceipt` | Execution outcome including events, logs, fee breakdown, and substate diff |
## License
BSD-3-Clause. Copyright 2026 The Tari Project.