create

Call v273 → current #0

Creates a new crowdloan campaign to raise funds for a project.

View calls on chain

Call Workflow

create

1. Validation

Signature, nonce, mortality, fees

Signature

Nonce

Mortality

Fee payment

2. Pre-dispatch

Permission & state checks

Permission checks

State validation

3. Dispatch

Execute logic, modify state

Created Crowdloans NextCrowdloanId

4. Post-dispatch

Final result & fee settlement

ExtrinsicSuccess

Fees settled

Svelte Flow

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Used by: developerssubnet ownersstakers

The Big Picture

Enables decentralized fundraising on Bittensor with built-in protections.

Use Cases

Launch crowdfunding campaign
Raise TAO for subnet development

From Chain Metadata

Create a crowdloan that will raise funds up to a maximum cap and if successful, will transfer funds to the target address if provided and dispatch the call (using creator origin). The initial deposit will be transfered to the crowdloan account and will be refunded in case the crowdloan fails to raise the cap. Additionally, the creator will pay for the execution of the call. The dispatch origin for this call must be _Signed_. Parameters: `deposit`: The initial deposit from the creator. `min_contribution`: The minimum contribution required to contribute to the crowdloan. `cap`: The maximum amount of funds that can be raised. `end`: The block number at which the crowdloan will end. `call`: The call to dispatch when the crowdloan is finalized. `target_address`: The address to transfer the raised funds to if provided.

Input Parameters

#	Name	Type	Description
0	deposit	Compact<u64> Cpt BalanceOf<T>	deposit: Balance in chain native currency (RAO for TAO; ÷10⁹) (RAO -> TAO (/ 10^9))
1	min_contribution	Compact<u64> Cpt BalanceOf<T>	min_contribution: Balance in chain native currency (RAO for TAO; ÷10⁹) (SCALE compact -> integer)
2	cap	Compact<u64> Cpt BalanceOf<T>	cap: Balance in chain native currency (RAO for TAO; ÷10⁹) (SCALE compact -> integer)
3	end	Compact<u32> Cpt BlockNumberFor<T>	end: Block number (SCALE compact -> integer)
4	call	Option Option<Box<<T as Config>::RuntimeCall>>	call (Option)
5	target_address	Option Option<T::AccountId>	target_address: optional Account address (32 bytes, SS58-encoded)

Permissions

Origin

Signed

Required Role

Any

Permission data inferred from metadata. May be incomplete.

Requirements

Signer has sufficient balance for deposit
Cap exceeds deposit
End block is valid

Effects

Events Emitted

Created

Storage Modified

Crowdloans NextCrowdloanId

Postconditions

New crowdloan created
Deposit transferred
Created event emitted

Side Effects

NextCrowdloanId incremented

Code Examples

import { createClient, Binary } from "polkadot-api";
import { getWsProvider } from "polkadot-api/ws";
import { sub } from "@polkadot-api/descriptors"; // generated by: npx papi add sub -w wss://entrypoint-finney.opentensor.ai:443

const client = createClient(getWsProvider("wss://entrypoint-finney.opentensor.ai:443"));
const api = client.getTypedApi(sub);

// Build create call (typed, named args)
const deposit = 0n;
const min_contribution = 0n;
const cap = 0n;
const end = 0;
const call = undefined;
const target_address = undefined;

const tx = api.tx.Crowdloan.create({
  deposit,
  min_contribution,
  cap,
  end,
  call,
  target_address,
});

Runtime Info

Pallet Index: 27
Call Index: 0
First Version: v273
Current Version: v411

Back to Crowdloan Calls