> For the complete documentation index, see [llms.txt](/llms.txt)

# Aztec.nr Dependencies

This page lists the available Aztec.nr libraries. Add dependencies to the `[dependencies]` section of your `Nargo.toml`:

```toml
[dependencies]
aztec = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="aztec" }
# Add other libraries as needed
```

## Core

### Aztec (required)

```toml
aztec = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="aztec" }
```

The core Aztec library required for every Aztec.nr smart contract.

## Note Types

### Address Note

```toml
address_note = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="address-note" }
```

Provides `AddressNote`, a note type for storing `AztecAddress` values.

### Field Note

```toml
field_note = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="field-note" }
```

Provides `FieldNote`, a note type for storing a single `Field` value.

### Uint Note

```toml
uint_note = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="uint-note" }
```

Provides `UintNote`, a note type for storing `u128` values. Also includes `PartialUintNote` for partial note workflows where the value is completed in public execution.

### ECDSA public key note

```toml
ecdsa_public_key_note = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="ecdsa-public-key-note" }
```

Provides `EcdsaPublicKeyNote`, a note type for storing an ECDSA public key as its 32-byte `x` and `y` coordinates.

## State Variables

### Balance Set

```toml
balance_set = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="balance-set" }
```

Provides `BalanceSet`, a state variable for managing private balances. Includes helper functions for adding, subtracting, and querying balances.

## Utilities

### Compressed String

```toml
compressed_string = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="compressed-string" }
```

Provides `CompressedString` and `FieldCompressedString` utilities for working with compressed string data.

## Protocol contract interfaces

The protocol contracts do not generate Aztec.nr call interfaces. Depend on these crates to call them from your contract.

### Contract instance registry

```toml
contract_instance_registry = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="contract-instance-registry-interface" }
```

Provides the `ContractInstanceRegistry` interface, used for example to [upgrade a contract](/developers/docs/aztec-nr/framework-description/contract_upgrades.md).

### Fee juice

```toml
fee_juice = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="fee-juice-interface" }
```

Provides the `FeeJuice` interface, for example to read a public fee juice balance with `balance_of_public`.

## Updating your aztec dependencies

When `aztec compile` warns that your aztec dependency tag does not match the CLI version, update the `tag` field in every Aztec.nr entry in your `Nargo.toml` to match the CLI version you are running.

For example, if your CLI is `v6.0.0`, change:

```toml
aztec = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v<old-version>", directory="aztec" }
```

to:

```toml
aztec = { git="https://github.com/aztec-labs-eng/aztec-nr/", tag="v6.0.0", directory="aztec" }
```

Repeat for every other Aztec.nr dependency in your `Nargo.toml` (e.g. `address_note`, `balance_set`, etc.). You can check your current CLI version with `aztec --version`.