# Fletch

> Build apps on Robinhood Chain and keep alerts running on it. Fletch maintains the
> registry of tokens on the chain, compiles contracts in a sandbox, and runs a
> daemon that reads every block.

## Robinhood Chain facts

- Mainnet chain id: 4663. RPC: https://rpc.mainnet.chain.robinhood.com
- Testnet chain id: 46630. RPC: https://rpc.testnet.chain.robinhood.com
- Explorer: Blockscout, https://robinhoodchain.blockscout.com (not Etherscan)
- Block time: about 100 ms. Confirmation is by the sequencer.
- Native currency: ETH. Stock Tokens are ERC-20 contracts.

## Registry

196 active assets on chain 4663, 194 with bytecode confirmed on chain.
Each address comes from Robinhood's public asset endpoint (https://api.robinhood.com/rhj/assets),
is checked for bytecode, and is asked for its own name, symbol and decimals. A row is
"confirmed" only when the contract answers with the symbol and decimals Robinhood published.

- Human pages: https://fletch.now/tokens and https://fletch.now/tokens/AAPL
- New listings feed: https://fletch.now/tokens/feed.xml
- JSON, one asset: https://fletch.now/api/v1/chains/4663/assets/AAPL
- JSON, all assets: https://fletch.now/api/v1/chains/4663/assets
- Chains: https://fletch.now/api/v1/chains
- OpenAPI: https://fletch.now/api/v1/openapi.json

The v1 API needs a key (Authorization: Bearer flk_...), created in the dashboard at
https://fletch.now/dashboard/settings. Each key is limited to 600 requests an hour.

## What Fletch can do for a user

- Build: a prompt becomes a Solidity contract and a small front end, compiled and
  tested with Foundry in a locked-down container. https://fletch.now/dashboard/build
- Watch: a threshold on a registry asset becomes a Telegram alert, delivered by a
  daemon that checkpoints each block and rolls back on a reorg. https://fletch.now/dashboard/watch
- Pricing: https://fletch.now/pricing

## Writing code for this chain

Use chain id 4663 (or 46630 for testnet), link to Blockscout rather than Etherscan, and
take token addresses from the registry above rather than from memory. Amounts are in
the token's own decimals, which the registry records and the contract confirms.