BRC2.0 Integration

BRC2.0 Metaprotocol runs EVM-compatible smart contracts on Bitcoin. If you write Solidity, you can deploy and call contracts here with tooling you already know, and reach Bitcoin-backed frBTC from inside them. This page covers the developer workflow through alkanes-cli. For the concept, see BRC2.0 Metaprotocol; for the full command list, see the CLI & SDK Reference.

The endpoint

BRC2.0 has its own JSON-RPC endpoint, separate from the Alkanes one. Pass it with --brc20-prog-rpc-url:

alkanes-cli -p mainnet \
  --brc20-prog-rpc-url https://mainnet.subfrost.io/v4/jsonrpc/brc20-prog \
  brc20-prog block-number

It speaks standard Ethereum JSON-RPC (eth_call, eth_getBalance, eth_getCode, eth_getLogs, eth_chainId, and the rest, see the BRC20 Programmable Module (JSON-RPC) reference for the full method list), plus a few brc20_* methods for inscription-aware lookups.

Deploying a contract

Compile your contract with Foundry, then deploy the build JSON:

alkanes-cli -p mainnet \
  --brc20-prog-rpc-url https://mainnet.subfrost.io/v4/jsonrpc/brc20-prog \
  --wallet-file ~/.alkanes/wallet.json \
  --passphrase "your-passphrase" \
  brc20-prog deploy-contract ./out/MyContract.sol/MyContract.json \
  --fee-rate 10

Useful flags:

Flag	Description
--from <addresses>	Addresses to source UTXOs from
--change <address>	Change address
--no-activation	Skip the activation transaction (use the two-transaction commit/reveal pattern)
--trace	Enable transaction tracing
--mine	Mine a block after broadcasting (regtest only)

A deploy is carried by a Bitcoin inscription with a commit-then-reveal flow. By default the tooling also sends an activation transaction, a third transaction after the commit and reveal; pass --no-activation to skip it and use only the two-transaction commit/reveal pattern. If any of your UTXOs carry inscriptions, the tooling automatically inserts a split transaction first, moving the inscribed sats to a safe output before spending clean sats for the commit, and broadcasts the bundle atomically.

Calling a contract

State-changing calls use transact; read-only calls use call:

# State-changing: transfer(address, uint256)
alkanes-cli -p mainnet \
  --brc20-prog-rpc-url https://mainnet.subfrost.io/v4/jsonrpc/brc20-prog \
  --wallet-file ~/.alkanes/wallet.json \
  --passphrase "your-passphrase" \
  brc20-prog transact --address 0xYourContract --signature "transfer(address,uint256)" --calldata "0xRecipient,1000" \
  --fee-rate 10

# Read-only (eth_call): raw calldata
alkanes-cli -p mainnet \
  --brc20-prog-rpc-url https://mainnet.subfrost.io/v4/jsonrpc/brc20-prog \
  brc20-prog call --to 0xYourContract --data 0x70a08231...

transact takes a human-readable function signature (--signature) and comma-separated arguments (--calldata), so you do not encode the calldata by hand. call takes raw ABI-encoded data, mirroring eth_call.

Wrapping BTC into a contract call

wrap-and-execute2 wraps BTC to frBTC and calls a target contract in the same flow, so a user can go from native BTC to a contract interaction in one step. --signature names the function to call on --target; pass its arguments as comma-separated values with --calldata (empty by default, so deposit() needs none):

alkanes-cli -p mainnet \
  --brc20-prog-rpc-url https://mainnet.subfrost.io/v4/jsonrpc/brc20-prog \
  --wallet-file ~/.alkanes/wallet.json \
  --passphrase "your-passphrase" \
  brc20-prog wrap-and-execute2 100000 \
  --target 0xYourContract \
  --signature "deposit()" \
  --fee-rate 10 \
  -y

To wrap BTC to frBTC without calling a contract, use brc20-prog wrap-btc <AMOUNT> --from <ADDRESSES> instead.

Reading state

# frBTC balance of an address (eth_getBalance)
brc20-prog get-balance 0xYourAddress

# Contract bytecode (eth_getCode)
brc20-prog get-code 0xYourContract

# Event logs (eth_getLogs)
brc20-prog get-logs --address 0xYourContract --from-block 840000 --to-block latest

Where to go next

• BRC2.0 Metaprotocol: how the protocol works.
• CLI & SDK Reference: every brc20-prog command and flag.
• Wrapping frBTC: the Alkanes-side wrap flow.