Precompiles reference

ArbOS provides child chain-specific precompiles with methods smart contracts can call the same way they can solidity functions. This reference page exhaustively documents the specific calls ArbOS makes available through precompiles. For a more conceptual description of what precompiles are and how they work, please refer to the precompiles conceptual page.

This reference page is divided into two sections. The first one lists all precompiles in a summary table with links to the reference of the specific precompile, along with the address where they live, their purpose and links to the go implementation and solidity interface. The second one details the methods available in each precompile with links to the specific implementation.

General information of precompiles

This section is divided into two tables. We first list precompiles we expect users to most often use, and then the rest of precompiles. However, both tables display the same information: name and purpose of the precompile, address, and links to the solidity interface and the go implementation.

Common precompiles

Precompile	Address	Solidity interface	Go implementation	Purpose
ArbAggregator	0x6d	Interface	Implementation	Configuring transaction aggregation
ArbGasInfo	0x6c	Interface	Implementation	Info about gas pricing
ArbRetryableTx	0x6e	Interface	Implementation	Managing retryables
ArbSys	0x64	Interface	Implementation	System-level functionality
ArbWasm	0x71	Interface	Implementation	Manages Stylus contracts
ArbWasmCache	0x72	Interface	Implementation	Manages Stylus cache

Other precompiles

Precompile	Address	Solidity interface	Go implementation	Purpose
ArbAddressTable	0x66	Interface	Implementation	Supporting compression of addresses
ArbBLS	-	-	-	Disabled (Former registry of BLS public keys)
ArbDebug	0xff	Interface	Implementation	Testing tools
ArbFunctionTable	0x68	Interface	Implementation	No longer used
ArbInfo	0x65	Interface	Implementation	Info about accounts
ArbOwner	0x70	Interface	Implementation	Chain administration, callable only by chain owner
ArbOwnerPublic	0x6b	Interface	Implementation	Info about chain owners
ArbosTest	0x69	Interface	Implementation	No longer used
ArbStatistics	0x6f	Interface	Implementation	Info about the pre-Nitro state

Precompiles reference

ArbAddressTable

ArbAddressTable (Interface | Implementation) provides the ability to create short-hands for commonly used accounts.

Precompile address: 0x0000000000000000000000000000000000000066

Method	Solidity interface	Go implementation	Description

ArbAggregator

ArbAggregator (Interface | Implementation) provides aggregators and their users methods for configuring how they participate in parent chain aggregation. Arbitrum One's default aggregator is the Sequencer, which a user will prefer unless SetPreferredAggregator is invoked to change it.

Compression ratios are measured in basis points. Methods that are checkmarked are access-controlled and will revert if not called by the aggregator, its fee collector, or a chain owner.

Precompile address: 0x000000000000000000000000000000000000006D

Method	Solidity interface	Go implementation	Description
⚠️undefined	Interface	Implementation	undefined
⚠️undefined	Interface	Implementation	undefined
⚠️undefined	Interface	Implementation	undefined
⚠️undefined	Interface	Implementation	undefined

Note: methods marked with ⚠️ are deprecated and their use is not supported.

ArbBLS

Disabled

This precompile has been disabled. It previously provided a registry of BLS public keys for accounts.

ArbDebug

ArbDebug (Interface | Implementation) provides mechanisms useful for testing. The methods of ArbDebug are only available for chains with the AllowDebugPrecompiles chain parameter set. Otherwise, calls to this precompile will revert.

Precompile address: 0x00000000000000000000000000000000000000ff

Method	Solidity interface	Go implementation	Description

Event	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	Emitted in Events for testing
undefined	Interface	Implementation	Emitted in Events for testing
undefined	Interface	Implementation	Never emitted (used for testing log sizes)

ArbFunctionTable

ArbFunctionTable (Interface | Implementation) provides aggregators the ability to manage function tables, to enable one form of transaction compression. The Nitro aggregator implementation does not use these, so these methods have been stubbed and their effects disabled. They are kept for backwards compatibility.

Precompile address: 0x0000000000000000000000000000000000000068

Method	Solidity interface	Go implementation	Description

ArbGasInfo

ArbGasInfo (Interface | Implementation) provides insight into the cost of using the chain. These methods have been adjusted to account for Nitro's heavy use of calldata compression. Of note to end-users, we no longer make a distinction between non-zero and zero-valued calldata bytes.

Precompile address: 0x000000000000000000000000000000000000006C

Method	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	GetCurrentTxL1GasFees gets the fee in wei paid to the batch poster for posting this tx
undefined	Interface	Implementation	undefined (Available since ArbOS 20)
undefined	Interface	Implementation	undefined (Available since ArbOS 20)
undefined	Interface	Implementation	undefined (Available since ArbOS 20)
undefined	Interface	Implementation	undefined (Available since ArbOS 20)
undefined	Interface	Implementation	undefined (Available since ArbOS 20)

ArbInfo

ArbInfo (Interface | Implementation) provides the ability to lookup basic info about accounts and contracts.

Precompile address: 0x0000000000000000000000000000000000000065

Method	Solidity interface	Go implementation	Description

ArbosTest

ArbosTest (Interface | Implementation) provides a method of burning arbitrary amounts of gas, which exists for historical reasons. In Classic, ArbosTest had additional methods only the zero address could call. These have been removed since users don't use them and calls to missing methods revert.

Precompile address: 0x0000000000000000000000000000000000000069

Method	Solidity interface	Go implementation	Description

ArbOwner

ArbOwner (Interface | Implementation) provides owners with tools for managing the rollup. Calls by non-owners will always revert.

Most of Arbitrum Classic's owner methods have been removed since they no longer make sense in Nitro:

• What were once chain parameters are now parts of ArbOS's state, and those that remain are set at genesis.
• ArbOS upgrades happen with the rest of the system rather than being independent
• Exemptions to address aliasing are no longer offered. Exemptions were intended to support backward compatibility for contracts deployed before aliasing was introduced, but no exemptions were ever requested.

Precompile address: 0x0000000000000000000000000000000000000070

Method	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	Sets the Brotli compression level used for fast compression (default level is 1)

ArbOwnerPublic

ArbOwnerPublic (Interface | Implementation) provides non-owners with info about the current chain owners.

Precompile address: 0x000000000000000000000000000000000000006b

Method	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	undefined (Available since ArbOS 11)

Event	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	Emitted when verifying a chain owner

ArbRetryableTx

ArbRetryableTx (Interface | Implementation) provides methods for managing retryables. The model has been adjusted for Nitro, most notably in terms of how retry transactions are scheduled. For more information on retryables, please see the retryable documentation.

Precompile address: 0x000000000000000000000000000000000000006E

Method	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	Gets the redeemer of the current retryable redeem attempt

Event	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	Emitted when creating a retryable
undefined	Interface	Implementation	Emitted when extending a retryable's expiry date
undefined	Interface	Implementation	Emitted when scheduling a retryable
undefined	Interface	Implementation	Emitted when cancelling a retryable
undefined	Interface	Implementation	DEPRECATED in favour of new RedeemScheduled event after the nitro upgrade.

ArbStatistics

ArbStatistics (Interface | Implementation) provides statistics about the chain as of just before the Nitro upgrade. In Arbitrum Classic, this was how a user would get info such as the total number of accounts, but there are better ways to get that info in Nitro.

Precompile address: 0x000000000000000000000000000000000000006F

Method	Solidity interface	Go implementation	Description

ArbSys

ArbSys (Interface | Implementation) provides system-level functionality for interacting with the parent chain and understanding the call stack.

Precompile address: 0x0000000000000000000000000000000000000064

Method	Solidity interface	Go implementation	Description

Event	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	Logs a send transaction from L2 to L1, including data for outbox proving
undefined	Interface	Implementation	DEPRECATED in favour of the new L2ToL1Tx event above after the nitro upgrade
undefined	Interface	Implementation	Logs a new merkle branch needed for constructing outbox proofs

ArbWasm

ArbWasm (Interface | Implementation) provides helper methods for managing Stylus contracts

Precompile address: 0x0000000000000000000000000000000000000071

Method	Solidity interface	Go implementation	Description

Event	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	Emitted when activating a WASM program
undefined	Interface	Implementation	Emitted when extending the expiration date of a WASM program

ArbWasmCache

ArbWasmCache (Interface | Implementation) provides helper methods for managing Stylus cache

Precompile address: 0x0000000000000000000000000000000000000072

Method	Solidity interface	Go implementation	Description

Event	Solidity interface	Go implementation	Description
undefined	Interface	Implementation	Emitted when caching a WASM program