> For the complete documentation index, see [llms.txt](https://docs.feel.cash/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.feel.cash/developers-and-integrators/contracts.md).

# Contracts and protocol

Identify Feel.cash launches by chain, contract, onchain launch proof, and public API records. Review supported networks and protocol infrastructure.

Feel.cash markets are designed to be easy to recognize and straightforward to index. The contract address and chain are always the canonical identity of a coin.

## Supported chains

| Item                | Base                              | Robinhood Chain                                      | Arc                                                                      | Solana                               |
| ------------------- | --------------------------------- | ---------------------------------------------------- | ------------------------------------------------------------------------ | ------------------------------------ |
| Chain ID            | `8453`                            | `4663`                                               | `5042`                                                                   | None; the API reports `1399811149`   |
| Default market pair | WETH; USDC is selectable          | WETH or the pair recorded for the launch             | USDC; EURC and cirBTC are selectable                                     | SOL; USDC and xStocks are selectable |
| Cash settlement     | The user's Cash balance           | The user's Cash balance                              | The user's Cash balance; EURC and cirBTC pairs can pay in the pair asset | The user's Cash balance              |
| Explorer            | [BaseScan](https://basescan.org/) | [Blockscout](https://robinhoodchain.blockscout.com/) | [Arc Explorer](https://explorer.arc.io/)                                 | [Solscan](https://solscan.io/)       |

The sections below describe Base, Robinhood Chain, and Arc. Solana launches use different infrastructure, described in [Solana launches](#solana-launches).

Base USDC:

```
0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
```

Cash, launch payments, Creator Fees, and Referral Fees use this token. A market can trade on another supported chain while payouts still arrive in the user's Cash balance.

## Onchain launch proof

Feel.cash launches through Doppler's Airlock contracts. The Airlock and integrator are not two separate proofs: they are two parts of the same creation transaction.

| Part                       | What it proves                                                          |
| -------------------------- | ----------------------------------------------------------------------- |
| **Doppler Airlock**        | The transaction used the expected deployment system on that chain       |
| **Feel.cash integrator**   | The `Airlock.create()` call recorded Feel.cash as the launch integrator |
| **Airlock `Create` event** | The transaction created the token address being checked                 |

The production integrator recorded in current Feel.cash creation calls is:

```
0x3879B1Ee8389FfeFb7afd51b1bafb9fAF23d6699
```

Airlock is chain-specific. The integrator is currently the same across supported EVM chains:

| Network         | Chain ID | Doppler Airlock                                                                                                                          | Feel.cash integrator                         |
| --------------- | -------: | ---------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------- |
| Base            |   `8453` | [`0x660eAaEdEBc968f8f3694354FA8EC0b4c5Ba8D12`](https://basescan.org/address/0x660eAaEdEBc968f8f3694354FA8EC0b4c5Ba8D12)                  | `0x3879B1Ee8389FfeFb7afd51b1bafb9fAF23d6699` |
| Robinhood Chain |   `4663` | [`0xeb7c034704ef8dcd2d32324c1545f62fb4ad0862`](https://robinhoodchain.blockscout.com/address/0xeb7c034704ef8dcd2d32324c1545f62fb4ad0862) | `0x3879B1Ee8389FfeFb7afd51b1bafb9fAF23d6699` |
| Arc             |   `5042` | [`0x14870a3282bd707b252e3c0f356a68b4c8f6d2ff`](https://explorer.arc.io/address/0x14870a3282bd707b252e3c0f356a68b4c8f6d2ff)               | `0x3879B1Ee8389FfeFb7afd51b1bafb9fAF23d6699` |

To reproduce the onchain proof for a token:

1. a successful call to the Airlock listed for that chain;
2. the Feel.cash integrator in the decoded `Airlock.create()` calldata; and
3. the emitted `Create` event whose `asset` is the token being indexed.

These checks identify a launch with Feel.cash onchain attribution. They do not show that Feel.cash owns the token or holds user funds, and they are not a contract audit or creator endorsement.

The Airlock is shared infrastructure, and the integrator is an attribution value rather than a permissioned signature. Test or pre-rebrand records can carry the same onchain combination. Before presenting a launch as currently official, reconcile the token with the Feel.cash API and require `officialFeelLaunch: true`.

## The `0x…fee1` signature

Every EVM token contract address begins with `0x`. New official Feel.cash launch addresses are mined so the final four characters are `fee1`:

```
0x....................................fee1
```

The dots represent the rest of the 40 hexadecimal address characters; they are not part of the real address. Feel.cash verifies the complete address before broadcasting the launch transaction.

The `0x…fee1` pattern makes official launches easier to spot, but it is not proof on its own. Anyone can attempt to deploy an unrelated address with the same ending.

Always confirm the chain and complete contract address, complete [onchain launch proof](#onchain-launch-proof), pool, and Feel.cash API record.

## Current launch configuration

| Property                             | Current default                                                                                               |
| ------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| Token supply                         | 1,000,000,000                                                                                                 |
| Token supply placed in the pool      | 100%                                                                                                          |
| Creator allocation at launch         | 0%                                                                                                            |
| Creator LP withdrawal                | Not available                                                                                                 |
| Liquidity migration                  | Disabled; the launch pool is permanent                                                                        |
| Starting FDV target                  | Approximately $10,000                                                                                         |
| Uniswap v4 LP fee                    | 0%                                                                                                            |
| Trading fee after opening protection | 1.5% at the standard creator fee; up to 4% with a [custom creator fee](/economics/fees.md#custom-creator-fee) |
| Opening protection                   | 50%, decaying linearly to 1.5% over 15 seconds                                                                |
| Governance module                    | No-op                                                                                                         |
| Migration module                     | No-op                                                                                                         |

Markets use Uniswap v4 liquidity. The entire token supply enters the launch pool, governance and migration are disabled, and the creator cannot withdraw the LP position. The current deployment path uses Doppler/Airlock infrastructure to create the market and record the integrator; indexers do not need to depend on that provider name as the identity of a Feel.cash coin.

## What is immutable

The token contract, pool identity, curve, fee configuration, recipients, supply, salt, and integrator are fixed for each launch. Feel.cash cannot retroactively change those rules or replace a coin's contract.

Historical coins keep the configuration they launched with. Read each coin's record rather than applying today's defaults to every supported coin.

## Solana launches

Solana coins launch on Raydium LaunchLab under one Feel.cash platform, then graduate automatically to a Raydium liquidity pool.

| Item                                         | Value                                                                      |
| -------------------------------------------- | -------------------------------------------------------------------------- |
| Launch program (Raydium LaunchLab)           | `LanMV9sAd7wArD4vJFi2qDdfnVhFxYSUg6eADduJ3uj`                              |
| Feel.cash platform                           | `Fo1dp1JYQQWgYgAdiZWfmJpA7KRreCdCEyEEVcE1Q2TN`, administered by a multisig |
| Pool program after graduation (Raydium CPMM) | `CPMMoo8L3F4NbTegBCKVNunggL7H1ZpdTHKxQB5qKP1C`                             |
| Token program                                | Token-2022, `TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb`                  |

### Onchain launch proof on Solana

1. The mint is owned by Token-2022 and ends in `fee1`, in any letter case (for example `…Fee1`).
2. The launch pool is the account derived under the launch program from the seed `pool`, the coin's mint, and the pair's mint.
3. That pool records the Feel.cash platform above as its platform.

As on the EVM chains, this identifies a provenance candidate. Another launcher can name the same platform, and anyone can mine a `fee1` ending. Only a matching API record with `officialFeelLaunch: true` identifies an official Feel.cash launch.

### Token configuration

| Property                   | Value                                                                                    |
| -------------------------- | ---------------------------------------------------------------------------------------- |
| Standard                   | Token-2022                                                                               |
| Supply and decimals        | 1,000,000,000 with 6 decimals                                                            |
| Mint authority             | None; no more coins can be minted                                                        |
| Freeze authority           | None; balances cannot be frozen                                                          |
| Transfer fee               | None                                                                                     |
| Extensions                 | Metadata pointer and token metadata only                                                 |
| Metadata                   | Name, symbol, and URI stored in the mint itself; the URI is served from `ipfs.feel.cash` |
| Creator or team allocation | 0%; no vesting or locked supply                                                          |
| Sold on the bonding curve  | 793,100,000 coins; the rest pairs with the funds raised at graduation                    |
| Liquidity after graduation | Locked                                                                                   |
| Trading fee                | 1.5% in both phases; [split](/economics/fees.md#solana)                                  |

### Why some explorers show mutable metadata

A Solana coin's metadata has an update authority, so some explorers label it “mutable”. That authority is `WLHv2UAZm6z4KyaaELi5pjdbJh6RESMva1Rnn8pJVVh`, an address controlled by the Raydium launch program. It is not a wallet: neither the creator nor Feel.cash holds a key for it, and neither can change a coin's name, symbol, or image link.

Raydium's published program interface has no instruction that edits a coin's metadata. Raydium can upgrade its own programs, so this depends on Raydium rather than on a guarantee Feel.cash can make.

### What is fixed on Solana

The mint address, supply, decimals, pairing, curve, graduation rule, and the absence of mint and freeze authorities are fixed at launch. Feel.cash cannot change them or replace a coin.

Two things sit outside the coin itself: Raydium controls and can upgrade its programs, and an xStock used as a pairing remains under its issuer's controls.

## Recommended verification sequence

1. Resolve the coin by chain and contract through the [Public API v1](/developers-and-integrators/api.md).
2. Confirm `officialFeelLaunch: true`.
3. Confirm the complete contract address and chain ID.
4. Confirm the creation transaction called the chain-specific Doppler Airlock.
5. Decode `Airlock.create()` and match the production integrator.
6. Match the token to the `asset` emitted in the Airlock `Create` event.
7. Inspect the pool and read the coin's own fee and market configuration.

For a Solana coin, replace steps 4 to 6 with the [Solana launch proof](#onchain-launch-proof-on-solana).
