# tari_engine
[](https://crates.io/crates/tari_engine)
[](https://docs.rs/tari_engine)
The Tari template execution engine. It loads compiled WASM templates, executes
transactions against them, manages state transitions, and enforces fee and
authorisation rules.
## Key components
| `TransactionProcessor` | Drives execution of a `Transaction` through the runtime |
| `RuntimeModule` | Trait for plugging custom runtime behaviour (fee modules, call tracking, …) |
| `WasmModule` / `LoadedWasmTemplate` | Loads and instruments a compiled template binary with gas metering |
| `MemoryStateStore` | In-process state backend used in tests and benchmarks |
| `FeeModule` / `FeeTable` | Configurable fee schedule applied during execution |
| `AuthParams` / `AuthorizationScope` | Signer-key context propagated into every call frame |
> **Note:** The engine is typically consumed through `tari_template_test_tooling`
> in tests, or by validator nodes in production. Direct use is needed only when
> embedding the engine in a custom host.
## License
BSD-3-Clause. Copyright 2026 The Tari Project.