Dev Gas Revenue Mechanism

The devgas module of Nibiru Chain shares contract execution fees with smart contract developers. This aims to increase the adoption of Nibiru by offering CosmWasm smart contract developers a direct source of income based on usage.

Developers can register their smart contracts such that, every time someone interacts with a registered smart contract, the contract deployer or their assigned withdrawal account receives a part of the transaction fees.

Table of Contents

• Register a Contract Withdrawal Address
  • Register Args
  • Description
  • Permissions
  • Exceptions
• Update a Contract's Withdrawal Address
  • Update Exception
• Concepts
  • FeeShare
  • Registration
  • Fee Distribution
  • WASM Transaction Fees
• State
  • State: FeeShare
    • State: ContractAddress
    • DeployerAddress
    • WithdrawerAddress
  • Genesis State
• State Transitions
  • Register Fee Share
  • Update Fee Split
  • Cancel Fee Split
• TxMsgs - devgas
  • MsgRegisterFeeShare
  • MsgUpdateFeeShare
  • MsgCancelFeeShare
• Ante Handler
• Events
  • Event: Register Fee Split
  • Event: Update Fee Split
  • Event: Cancel Fee Split
• Module Parameters
• Enable FeeShare Module
  • Developer Shares Amount
  • Allowed Denominations
• Clients
  • Command Line Interface
  • CLI: Queries
  • CLI: Transactions
• gRPC Queries
  • gRPC Transactions
• Credits: Evmos

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Register a Contract Withdrawal Address

Copy nibid tx devgas register [contract_bech32] [withdraw_bech32] --from [key]

Registers the withdrawal address for the given contract.

Register Args

contract_bech32 (string, required): The bech32 address of the contract whose interaction fees will be shared.

withdraw_bech32 (string, required): The bech32 address where the interaction fees will be sent every block.

Description

This command registers the withdrawal address for the given contract. Any time a user interacts with your contract, the funds will be sent to the withdrawal address. It can be any valid address, such as a DAO, normal account, another contract, or a multi-sig.

Permissions

This command can only be run by the admin of the contract. If there is no admin, then it can only be run by the contract creator.

Exceptions

• withdraw_bech32 can not be the community pool (distribution) address. This is a limitation of the way the SDK handles this module account

• For contracts created or administered by a contract factory, the withdrawal address can only be the same as the contract address. This can be registered by anyone, but it's unchangeable. This is helpful for SubDAOs or public goods to save fees in the treasury.

If you create a contract like this, it's best to create an execution method for withdrawing fees to an account. To do this, you'll need to save the withdrawal address in the contract's state before uploading a non-migratable contract.

Update a Contract's Withdrawal Address

This can be changed at any time so long as you are still the admin or creator of a contract with the command:

Copy nibid tx devgas update [contract] [new_withdraw_address]

Update Exception

This can not be done if the contract was created from or is administered by another contract (a contract factory). There is not currently a way for a contract to change its own withdrawal address directly.

Concepts

FeeShare

The DevGas (x/devgas) module is a revenue-per-gas model, which allows developers to get paid for deploying their decentralized applications (dApps) on Nibiru. This helps developers to generate revenue every time a user invokes their contracts to execute a transaction on the chain.

This registration is permissionless to sign up for and begin earning fees from. By default, 50% of all gas fees for Execute Messages are shared. This can be changed by governance and implemented by the x/devgas module.

Registration

Developers register their contract applications to gain their cut of fees per execution. Any contract can be registered by a developer by submitting a signed transaction. After the transaction is executed successfully, the developer will start receiving a portion of the transaction fees paid when a user interacts with the registered contract. The developer can have the funds sent to their wallet, a DAO, or any other wallet address on the Nibiru.

NOTE: If your contract is part of a development project, please ensure that the deployer of the contract (or the factory/DAO that deployed the contract) is an account that is owned by that project. This avoids the situation, that an individual deployer who leaves your project could become malicious.

Fee Distribution

As described above, developers will earn a portion of the transaction fee after registering their contracts. To understand how transaction fees are distributed, we will look at the following in detail:

• The transactions eligible are only Wasm Execute Txs (opens new window) (MsgExecuteContract).

WASM Transaction Fees

Users pay transaction fees to pay to interact with smart contracts on Nibiru. When a transaction is executed, the entire fee amount (gas limit * gas price) is sent to the FeeCollector module account during the Cosmos SDK AnteHandler (opens new window) execution.

After this step, the FeeCollector sends 50% of the funds and splits them between contracts that were executed on the transaction. If the fees paid are not accepted by governance, there is no payout to the developers (for example, niche base tokens) for tax purposes. If a user sends a message and it does not interact with any contracts (ex: bankSend), then the entire fee is sent to the FeeCollector as expected.

State

The x/devgas module keeps the following objects in the state:

State Object	Description	Key	Value	Store
FeeShare	Fee split bytecode	[]byte{1} + []byte(contract_address)	[]byte{feeshare}	KV
DeployerFeeShares	Contract by deployer address bytecode	[]byte{2} + []byte(deployer_address) + []byte(contract_address)	[]byte{1}	KV
FeeSharesByWithdrawer	Contract by withdraw address bytecode	[]byte{3} + []byte(withdraw_address) + []byte(contract_address)	[]byte{1}	KV

State: FeeShare

A FeeShare defines an instance that organizes fee distribution conditions for the owner of a given smart contract

Copy type FeeShare struct { // contract_address is the bech32 address of a registered contract in string form ContractAddress string `protobuf:"bytes,1,opt,name=contract_address,json=contractAddress,proto3" json:"contract_address,omitempty"` // deployer_address is the bech32 address of message sender. It must be the // same as the contracts admin address. DeployerAddress string `protobuf:"bytes,2,opt,name=deployer_address,json=deployerAddress,proto3" json:"deployer_address,omitempty"` // withdrawer_address is the bech32 address of account receiving the // transaction fees. WithdrawerAddress string `protobuf:"bytes,3,opt,name=withdrawer_address,json=withdrawerAddress,proto3" json:"withdrawer_address,omitempty"` }

State: ContractAddress

ContractAddress defines the contract address that has been registered for fee distribution.

DeployerAddress

A DeployerAddress is the admin address for a registered contract.

WithdrawerAddress

The WithdrawerAddress is the address that receives transaction fees for a registered contract.

Genesis State

The x/devgas module's GenesisState defines the state necessary for initializing the chain from a previously exported height. It contains the module parameters and the fee share for registered contracts:

Copy // GenesisState defines the module's genesis state. type GenesisState struct { // module parameters Params Params `protobuf:"bytes,1,opt,name=params,proto3" json:"params"` // active registered contracts for fee distribution FeeShares []FeeShare `protobuf:"bytes,2,rep,name=feeshares,json=feeshares,proto3" json:"feeshares"` }

State Transitions

The x/devgas module allows for three types of state transitions: RegisterFeeShare, UpdateFeeShare and CancelFeeShare. The logic for distributing transaction fees is handled through the Ante handler.

Register Fee Share

A developer registers a contract for receiving transaction fees by defining the contract address and the withdrawal address for fees to be paid too. If this is not set, the developer can not get income from the contract. This is opt-in for tax purposes. When registering for fees to be paid, you MUST be the admin of said wasm contract. The withdrawal address can be the same as the contract's address if you so choose.

1. User submits a RegisterFeeShare to register a contract address, along with a withdrawal address that they would like to receive the fees to
2. Check if the following conditions pass:
   1. x/devgas module is enabled via Governance
   2. the contract was not previously registered
   3. deployer has a valid account (it has done at least one transaction)
   4. the contract address exists
   5. the deployer signing the transaction is the admin of the contract
   6. the contract is already deployed
3. Store an instance of the provided share.

All transactions sent to the registered contract occurring after registration will have their fees distributed to the developer, according to the global DeveloperShares parameter in governance.

Update Fee Split

A developer updates the withdraw address for a registered contract, defining the contract address and the new withdraw address.

1. The user submits a UpdateFeeShare
2. Check if the following conditions pass:
   1. x/devgas module is enabled
   2. the contract is registered
   3. the signer of the transaction is the same as the contract admin per the WasmVM
3. Update the fee with the new withdrawal address.

After this update, the developer receives the fees on the new withdrawal address.

Cancel Fee Split

A developer cancels receiving fees for a registered contract, defining the contract address.

1. The user submits a CancelFeeShare
2. Check if the following conditions pass:
   1. x/devgas module is enabled
   2. the contract is registered
   3. the signer of the transaction is the same as the contract admin per the WasmVM
3. Remove share from storage

The developer no longer receives fees from transactions sent to this contract. All fees go to the community.

TxMsgs - devgas

This section defines the sdk.Msg concrete types that result in the state transitions defined on the previous section.

MsgRegisterFeeShare

Defines a transaction signed by a developer to register a contract for transaction fee distribution. The sender must be an EOA that corresponds to the contract deployer address.

Copy type MsgRegisterFeeShare struct { // contract_address in bech32 format ContractAddress string `protobuf:"bytes,1,opt,name=contract_address,json=contractAddress,proto3" json:"contract_address,omitempty"` // deployer_address is the bech32 address of message sender. It must be the // same the contract's admin address DeployerAddress string `protobuf:"bytes,2,opt,name=deployer_address,json=deployerAddress,proto3" json:"deployer_address,omitempty"` // withdrawer_address is the bech32 address of account receiving the // transaction fees WithdrawerAddress string `protobuf:"bytes,3,opt,name=withdrawer_address,json=withdrawerAddress,proto3" json:"withdrawer_address,omitempty"` }

The message content stateless validation fails if:

• Contract bech32 address is invalid
• Deployer bech32 address is invalid
• Withdraw bech32 address is invalid

MsgUpdateFeeShare

Defines a transaction signed by a developer to update the withdraw address of a contract registered for transaction fee distribution. The sender must be the admin of the contract.

Copy type MsgUpdateFeeShare struct { // contract_address in bech32 format ContractAddress string `protobuf:"bytes,1,opt,name=contract_address,json=contractAddress,proto3" json:"contract_address,omitempty"` // deployer_address is the bech32 address of message sender. It must be the // same the contract's admin address DeployerAddress string `protobuf:"bytes,2,opt,name=deployer_address,json=deployerAddress,proto3" json:"deployer_address,omitempty"` // withdrawer_address is the bech32 address of account receiving the // transaction fees WithdrawerAddress string `protobuf:"bytes,3,opt,name=withdrawer_address,json=withdrawerAddress,proto3" json:"withdrawer_address,omitempty"` }

The message content stateless validation fails if:

• Contract bech32 address is invalid
• Deployer bech32 address is invalid
• Withdraw bech32 address is invalid

MsgCancelFeeShare

Defines a transaction signed by a developer to remove the information for a registered contract. Transaction fees will no longer be distributed to the developer for this smart contract. The sender must be an admin that corresponds to the contract.

Copy type MsgCancelFeeShare struct { // contract_address in bech32 format ContractAddress string `protobuf:"bytes,1,opt,name=contract_address,json=contractAddress,proto3" json:"contract_address,omitempty"` // deployer_address is the bech32 address of message sender. It must be the // same the contract's admin address DeployerAddress string `protobuf:"bytes,2,opt,name=deployer_address,json=deployerAddress,proto3" json:"deployer_address,omitempty"` }

The message content stateless validation fails if:

• Contract bech32 address is invalid
• Contract bech32 address is zero
• Deployer bech32 address is invalid

Ante Handler

The fees module uses the ante handler to distribute fees between developers and the community.

An Ante Decorator executes custom logic after each successful WasmExecuteMsg transaction. All fees paid by a user for transaction execution are sent to the FeeCollector module account during the AnteHandler execution before being redistributed to the registered contract developers.

If the x/devgas module is disabled or the Wasm Execute Msg transaction targets an unregistered contract, the handler returns nil, without performing any actions. In this case, 100% of the transaction fees remain in the FeeCollector module, to be distributed elsewhere.

If the x/devgas module is enabled and a Wasm Execute Msg transaction targets a registered contract, the handler sends a percentage of the transaction fees (paid by the user) to the withdraw address set for that contract.

1. The user submits an Execute transaction (MsgExecuteContract) to a smart contract and the transaction is executed successfully
2. Check if
   • fees module is enabled
   • the smart contract is registered to receive fee split
3. Calculate developer fees according to the DeveloperShares parameter.
4. Check what fees governance allows to be paid in
5. Check which contracts the user executed that also have been registered.
6. Calculate the total amount of fees to be paid to the developer(s). If multiple, split the 50% between all registered withdrawal addresses.
7. Distribute the remaining amount in the FeeCollector to validators according to the SDK Distribution Scheme (opens new window).

Events

The x/devgas module emits the following events:

Event: Register Fee Split

Type	Attribute Key	Attribute Value
register_feeshare	"contract"	{msg.ContractAddress}
register_feeshare	"sender"	{msg.DeployerAddress}
register_feeshare	"withdrawer_address"	{msg.WithdrawerAddress}

Event: Update Fee Split

Type	Attribute Key	Attribute Value
update_feeshare	"contract"	{msg.ContractAddress}
update_feeshare	"sender"	{msg.DeployerAddress}
update_feeshare	"withdrawer_address"	{msg.WithdrawerAddress}

Event: Cancel Fee Split

Type	Attribute Key	Attribute Value
cancel_feeshare	"contract"	{msg.ContractAddress}
cancel_feeshare	"sender"	{msg.DeployerAddress}

Module Parameters

The fee Split module contains the following parameters:

Key	Type	Default Value
EnableFeeShare	bool	true
DeveloperShares	sdk.Dec	50%
AllowedDenoms	[]string{}	[]string(nil)

Enable FeeShare Module

The EnableFeeShare parameter toggles all state transitions in the module. When the parameter is disabled, it will prevent any transaction fees from being distributed to contract deplorers and it will disallow contract registrations, updates or cancellations.

Developer Shares Amount

The DeveloperShares parameter is the percentage of transaction fees that are sent to the contract deplorers.

Allowed Denominations

The AllowedDenoms parameter is used to specify which fees coins will be paid to contract developers. If this is empty, all fees paid will be split. If not, only fees specified here will be paid out to the withdrawal address.

Clients

Command Line Interface

Find below a list of nibid commands added with the x/devgas module. You can obtain the full list by using the nibid -h command. A CLI command can look like this:

Copy nibid query feeshare params

CLI: Queries

Command	Subcommand	Description
query feeshare	params	Get devgas params
query feeshare	contract	Get the devgas for a given contract
query feeshare	contracts	Get all feeshares
query feeshare	deployer-contracts	Get all feeshares of a given deployer
query feeshare	withdrawer-contracts	Get all feeshares of a given withdrawer

CLI: Transactions

Command	Subcommand	Description
tx feeshare	register	Register a contract for receiving devgas
tx feeshare	update	Update the withdraw address for a contract
tx feeshare	cancel	Remove the devgas for a contract

gRPC Queries

Verb	Method	Description
gRPC	nibiru.devgas.v1.Query/Params	Get devgas params
gRPC	nibiru.devgas.v1.Query/FeeShare	Get the devgas for a given contract
gRPC	nibiru.devgas.v1.Query/FeeShares	Get all feeshares
gRPC	nibiru.devgas.v1.Query/DeployerFeeShares	Get all feeshares of a given deployer
gRPC	nibiru.devgas.v1.Query/FeeSharesByWithdrawer	Get all feeshares of a given withdrawer
GET	/nibiru.devgas/v1/params	Get devgas params
GET	/nibiru.devgas/v1/feeshares/{contract_address}	Get the devgas for a given contract
GET	/nibiru.devgas/v1/feeshares	Get all feeshares
GET	/nibiru.devgas/v1/feeshares/{deployer_address}	Get all feeshares of a given deployer
GET	/nibiru.devgas/v1/feeshares/{withdraw_address}	Get all feeshares of a given withdrawer

gRPC Transactions

Verb	Method	Description
gRPC	nibiru.devgas.v1.Msg/RegisterFeeShare	Register a contract for receiving devgas
gRPC	nibiru.devgas.v1.Msg/UpdateFeeShare	Update the withdraw address for a contract
gRPC	nibiru.devgas.v1.Msg/CancelFeeShare	Remove the devgas for a contract
POST	/nibiru.devgas/v1/tx/register_feeshare	Register a contract for receiving devgas
POST	/nibiru.devgas/v1/tx/update_feeshare	Update the withdraw address for a contract
POST	/nibiru.devgas/v1/tx/cancel_feeshare	Remove the devgas for a contract