Become a Facilitator: Accelerate Sundial Transfers

Facilitators are voluntary intermediaries who speed up the deposit and withdrawal experience for Sundial users. Instead of waiting through the L2 maturity period themselves, users can opt for an accelerated transfer — and a Facilitator immediately fronts the funds on the destination chain in exchange for a fee. The Facilitator then waits out the maturity window and claims the L2 funds when they settle. You earn the spread between the fee you charge the user and your actual transaction cost; at volume, this becomes a reliable and scalable income stream.

How It Works

Sundial’s standard withdrawal flow requires a user to wait for the L2 maturity period before funds are available on L1. Facilitators compress this wait to near-zero for the user.

Accelerated Withdrawal
Accelerated Deposit

In a standard withdrawal, the user submits a withdrawal request from the L2 and waits for the maturity period to clear before receiving funds on L1. With a Facilitator:

User requests an accelerated withdrawal

The user selects a Facilitator from the public Facilitator Registry and initiates a withdrawal, agreeing to the Facilitator’s published fee rate.

Facilitator pays the user immediately

You release the withdrawal amount to the user’s L1 address from your own liquidity pool — the user receives funds right away, without waiting.

Facilitator claims the L2 funds

You hold the corresponding L2 withdrawal claim and wait out the maturity period. Once it clears, you claim the L2 funds and recover your capital plus the fee spread.

The maturity period exists to allow Watchers time to detect and challenge any invalid blocks. Once the window passes without a successful fraud proof, the funds are provably safe to release.

Incentives

Your revenue as a Facilitator comes from the spread between the fee you charge users and the actual on-chain transaction cost:

E[Payout_Fa] = λ_tx · (UserFee − TxFee) − C_operation − C_capital

Where:

λ_tx — number of transactions you facilitate
UserFee — fee you charge per transaction
TxFee — actual on-chain gas cost per transaction
C_operation — ongoing operating costs
C_capital — cost of deploying and maintaining your liquidity pool

Facilitated transactions are expected to be frequent, but individual fees are small. Volume is key: the more requests you can process quickly and reliably, the more you earn.

Your fee schedule is publicly visible in the Facilitator Registry. Users compare Facilitators when choosing accelerated withdrawals — competitive, transparent pricing attracts more volume than high rates.

Risk Profile

Facilitators take on L2 risk during the maturity window. If the L2 is found to be invalid during the window after you have already paid the user, you may not be able to recover the funds you fronted. Running a Prover alongside your Facilitator service is the primary mitigation — if you detect fraud yourself, you can challenge the block and recover your bond exposure before it affects your facilitated positions.

The risk window is bounded by the L2 maturity period. Once that period closes without a successful fraud proof, your claims are settled and your capital is recovered. Maintaining a healthy Prover service gives you the earliest possible warning of any L2 integrity issues.

Registering as a Facilitator

Facilitators register on-chain via the Facilitator Registry. Your registration includes your fee schedule, receipt address, and liquidity pool address. Once registered, your entry is publicly visible to users selecting a Facilitator for their withdrawal.

Registration Schema

The Watcher Toolkit provides the following endpoint definitions for Facilitator operations:

export const FacilitatorEndpoints = S.Struct({
  // Register as a new Facilitator with your fee schedule and addresses
  register: S.Function(
    S.Struct({
      fee: S.Number,                              // Your fee rate (as a fraction or basis points)
      receiptAddress: S.L1Address | S.L2Address,  // Address to receive facilitated funds
      lpAddress: S.L1Address | S.L2Address,       // Liquidity pool address
      credential: S.String                        // Your on-chain signing credential
    }),
    S.Void
  ),

  // Remove yourself from the Facilitator Registry
  unregister: S.Function(
    S.Struct({
      receiptAddress: S.L1Address | S.L2Address,
      credential: S.String
    }),
    S.Void
  ),

  // Update your fee rate, receipt address, or liquidity pool address
  updateRegistration: S.Function(
    S.Struct({
      fee: S.Number,
      receiptAddress: S.L1Address | S.L2Address,
      lpAddress: S.L1Address | S.L2Address,
      credential: S.String
    }),
    S.Void
  ),

  // Reference withdrawal transactions you facilitated on-chain
  referenceWithdrawals: S.Function(
    S.Array(
      S.Struct({
        transactionHash: S.String,              // Hash of the facilitated withdrawal tx
        value: S.Number,                        // Value of the withdrawal
        endUser: S.L1Address | S.L2Address      // End user's address
      }),
      S.Void
    ),
  ),
});

Key Registration Fields

number

required

Your fee rate for facilitated transactions. This is displayed publicly in the Facilitator Registry. Set this to a rate that covers your costs and opportunity cost of capital while remaining competitive.

string

required

The L1 or L2 address where you receive the user’s withdrawal claim after facilitating. Must be an address you control.

string

required

The address of your liquidity pool from which you front funds to users. Ensure this address has sufficient balance before registering.

string

required

Your on-chain signing credential used to authorize registry operations. Keep this secure — it authorizes updates and unregistration.

Getting Started

Fund your liquidity pool

Deposit wBTC into the address you intend to use as your lpAddress. Your pool balance caps the total value of withdrawals you can facilitate simultaneously. Start with an amount you are comfortable having locked during the maturity period.

Call the register endpoint with your fee rate, receipt address, liquidity pool address, and signing credential. After the transaction confirms, your Facilitator entry is live and visible to users.

await facilitator.register({
  fee: 0.001,            // 0.1% fee rate
  receiptAddress: "addr1...",
  lpAddress: "addr1...",
  credential: "your-credential-here"
});

Stake your challenge bond

In addition to your liquidity pool, you must stake a challenge bond. This bond is your commitment to honest facilitation and is required to reference withdrawals on-chain.

Start monitoring for requests

Deploy the Facilitator reference implementation from the Watcher Toolkit. The service monitors the withdrawal queue for requests directed at your Facilitator entry and automatically fronts transactions within your configured parameters.

sundial-watcher facilitator \
  --config ./facilitator-config.json \
  --lp-address addr1... \
  --receipt-address addr1...

Reference completed withdrawals

After the maturity period clears for withdrawals you’ve facilitated, call referenceWithdrawals to record them on-chain. This builds your verifiable facilitation history in the registry — a public track record that helps attract future users.

await facilitator.referenceWithdrawals([
  {
    transactionHash: "abc123...",
    value: 0.05,
    endUser: "addr1..."
  }
]);

Updating or Leaving the Registry

You can update your fee schedule or addresses at any time without losing your facilitation history. If you want to stop operating, call unregister to remove your entry from the public registry. Outstanding maturity periods for withdrawals you have already facilitated are unaffected — they continue to settle normally.

// Update fee rate
await facilitator.updateRegistration({
  fee: 0.0008,
  receiptAddress: "addr1...",
  lpAddress: "addr1...",
  credential: "your-credential-here"
});

// Unregister
await facilitator.unregister({
  receiptAddress: "addr1...",
  credential: "your-credential-here"
});

Facilitator Economics Summary

Factor	Impact
Fee rate	Higher rate = more per transaction, but lower user demand
Liquidity pool size	Larger pool = more simultaneous facilitations
Transaction volume	Primary revenue driver — volume compounds returns
Maturity window	Capital is locked for the maturity period per facilitated withdrawal
Running a Prover	Reduces L2 risk exposure during maturity window

Next Steps

Watcher Guide

Learn about the other three Watcher roles — Prover, Archivist, and Canary — that complement the Facilitator role.

Run a Prover

Provers monitor for fraud and claim slashed bonds. Running one alongside your Facilitator service is the best way to protect your liquidity.

Tokenomics

Full incentive math for Facilitators, including fee calibration and capital efficiency analysis.

Operator Guide

Consider also running a Layer Node to earn block production fees on top of your facilitation income.

Using Sundial

Network Participants

Become a Facilitator: Accelerate Sundial Transfers

How It Works

Incentives

Risk Profile

Registering as a Facilitator

Registration Schema

Key Registration Fields

Getting Started

Updating or Leaving the Registry

Facilitator Economics Summary

Next Steps

Watcher Guide

Run a Prover

Tokenomics

Operator Guide

​How It Works

​Incentives

​Risk Profile

​Registering as a Facilitator

​Registration Schema

​Key Registration Fields

​Getting Started

​Updating or Leaving the Registry

​Facilitator Economics Summary

​Next Steps

Watcher Guide

Run a Prover

Tokenomics

Operator Guide

How It Works

Incentives

Risk Profile

Registering as a Facilitator

Registration Schema

Key Registration Fields

Getting Started

Updating or Leaving the Registry

Facilitator Economics Summary

Next Steps