| name | exfer |
| version | 1.1.0 |
| description | Exfer is a permissionless proof-of-work blockchain for autonomous machine-to-machine commerce. It combines Argon2id memory-hard mining, an extended UTXO model, and Exfer Script โ a total functional combinator language โ for transaction conditions. Use when an agent needs to send payments, check balances, create hash-time-locked contracts (HTLCs), mine blocks, or interact with blockchain-based machine commerce.
|
| license | MIT |
| homepage | https://github.com/ahuman-exfer/exfer |
| metadata | {"author":"Exfer Contributors","repository":"https://github.com/ahuman-exfer/exfer","keywords":"payment, transfer, settlement, trustless, machine-to-machine, cryptocurrency, wallet, hash-lock, escrow, atomic, blockchain, proof-of-work","clawdbot":{"emoji":"๐ช","primaryEnv":"EXFER_PASS","requires":{"env":["EXFER_PASS"]}}} |
Exfer: A Peer-to-Peer Settlement Protocol for Autonomous Machines
Exfer is a permissionless proof-of-work blockchain for autonomous machine-to-machine commerce. It combines Argon2id memory-hard mining, an extended UTXO model, and Exfer Script โ a total functional combinator language โ for transaction conditions.
The protocol is the minimum infrastructure that turns independent agents into an economy.
All scripts terminate. Costs are statically computable before execution. The UTXO model eliminates global state and reentrancy. An autonomous agent can construct a transaction, compute its exact cost, and know with certainty that it will validate โ without simulating execution, competing in a fee auction, or reasoning about concurrent state changes. There is no gas estimation. There is no mempool priority auction.
Network
RPC="http://82.221.100.201:9334"
New nodes discover peers automatically via DNS โ no --peers flag needed. On startup, the node resolves seed.exfer.org which returns a random subset of healthy, synced nodes from the network. If DNS fails, it falls back to hardcoded seed IPs. To manually specify peers instead: --peers ip:port.
Genesis block ID: d7b6805c8fd793703db88102b5aed2600af510b79e3cb340ca72c1f762d1e051
Units
- 1 EXFER = 100,000,000 exfers (base unit)
- The
--amount and --fee flags accept both formats:
- Human-readable:
--amount "10 EXFER", --fee "0.5 EXFER"
- Base units:
--amount 1000000000
- Minimum output: 200 exfers (dust threshold)
- Default fee: 100,000 exfers (0.001 EXFER)
1. Install
Download pre-built binary (recommended)
curl -LO https://github.com/ahuman-exfer/exfer/releases/latest/download/exfer-linux-x86_64
chmod +x exfer-linux-x86_64
mv exfer-linux-x86_64 exfer
curl -LO https://github.com/ahuman-exfer/exfer/releases/latest/download/exfer-macos-arm64
chmod +x exfer-macos-arm64
xattr -d com.apple.quarantine exfer-macos-arm64
mv exfer-macos-arm64 exfer
curl -LO https://github.com/ahuman-exfer/exfer/releases/latest/download/exfer-macos-x86_64
chmod +x exfer-macos-x86_64
xattr -d com.apple.quarantine exfer-macos-x86_64
mv exfer-macos-x86_64 exfer
Windows
Invoke-WebRequest -Uri https://github.com/ahuman-exfer/exfer/releases/latest/download/exfer-windows-x86_64.exe -OutFile exfer.exe
Build from source
git clone https://github.com/ahuman-exfer/exfer.git
cd exfer
cargo build --release
Quick start
exfer init
One command: creates wallet, starts node, begins syncing. Use --json and --passphrase-env for non-interactive agent automation:
EXFER_PASS="your-passphrase" exfer init --passphrase-env EXFER_PASS --json
To also enable mining: exfer init --mine.
Verify
./target/release/exfer --help
Expected output:
Exfer blockchain node
Usage: exfer <COMMAND>
Commands:
node Run a full node
mine Run the miner
wallet Wallet operations
script Script operations (HTLC, covenants)
init Initialize a new Exfer node
help Print this message or the help of the given subcommand(s)
Options:
-h, --help Print help
2. Create a Wallet
Generate a new Ed25519 keypair encrypted with a passphrase:
exfer wallet generate --output ~/my-wallet.key --json
Output (JSON):
{
"address": "8d896d64864f53214acb49aeb44a09a03d5bb23d19a417a6ce7b0da65c7bd750",
"file": "~/my-wallet.key",
"pubkey": "fcbd5a818501cd5439ebe8c0c5ff244c0f1475333e226b7f998e6eb80552c69d"
}
Copy the .key file to a second location as backup. It is encrypted and safe to store anywhere.
The address is a 32-byte pubkey hash used to receive payments. The pubkey is used for mining payouts (via --miner-pubkey). The private key stays encrypted in the .key file.
View wallet info
exfer wallet info --wallet ~/my-wallet.key --json
3. Check Balance
Query a remote node via JSON-RPC (no local database needed):
exfer wallet balance \
--wallet ~/my-wallet.key \
--rpc $RPC \
--json
Output:
{
"address": "8d896d64864f53214acb49aeb44a09a03d5bb23d19a417a6ce7b0da65c7bd750",
"balance": 7368884920683,
"source": "rpc",
"rpc_url": "http://82.221.100.201:9334"
}
balance is in exfers (base units) โ divide by 100,000,000 for EXFER. This balance = 73,688.85 EXFER.
Check balance by address (RPC directly)
curl -s -X POST $RPC \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"method": "get_balance",
"params": {"address": "8d896d64864f53214acb49aeb44a09a03d5bb23d19a417a6ce7b0da65c7bd750"},
"id": 1
}'
4. Send a Payment
Send exfers to a recipient address via a remote node:
exfer wallet send \
--wallet ~/my-wallet.key \
--to 8d896d64864f53214acb49aeb44a09a03d5bb23d19a417a6ce7b0da65c7bd750 \
--amount "10 EXFER" \
--fee "0.001 EXFER" \
--rpc $RPC \
--json
--to: recipient address (64 hex chars)
--amount: amount in exfers or "10 EXFER" (both accepted)
--fee: transaction fee (default: 0.001 EXFER)
--rpc: remote node RPC URL (fetches UTXOs and submits the signed transaction)
Output:
{
"tx_id": "fb8a634fcce6cfc124de86fa0a4b3e6130a1e6bfda68a34dc4f30ec7a2a2b68c",
"size": 227,
"tip_height": 5553,
"submitted": true,
"rpc_url": "http://82.221.100.201:9334",
"rpc_result": {"tx_id": "fb8a634fcce6cfc124de86fa0a4b3e6130a1e6bfda68a34dc4f30ec7a2a2b68c"}
}
The transaction is signed locally (private key never leaves your machine) and submitted via RPC.
Wait for confirmation
Poll get_transaction with the tx_id until block_height appears:
TX_ID="fb8a634fcce6cfc124de86fa0a4b3e6130a1e6bfda68a34dc4f30ec7a2a2b68c"
for i in $(seq 1 60); do
RESULT=$(curl -s -X POST $RPC \
-H "Content-Type: application/json" \
-d "{\"jsonrpc\":\"2.0\",\"method\":\"get_transaction\",\"params\":{\"hash\":\"$TX_ID\"},\"id\":1}")
if echo "$RESULT" | grep -q '"block_height"'; then
echo "Confirmed: $RESULT"
break
fi
if [ "$i" -eq 60 ]; then
echo "ERROR: transaction not confirmed after 10 minutes"
exit 1
fi
echo "Pending... ($i/60)"
sleep 10
done
5. Check Transaction Status
curl -s -X POST $RPC \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"method": "get_transaction",
"params": {"hash": "fb8a634fcce6cfc124de86fa0a4b3e6130a1e6bfda68a34dc4f30ec7a2a2b68c"},
"id": 1
}'
Response:
{
"jsonrpc": "2.0",
"result": {
"tx_id": "fb8a634f...",
"tx_hex": "01000200...",
"in_mempool": false,
"block_hash": "169c02f4...",
"block_height": 5556
},
"id": 1
}
in_mempool: true โ pending confirmation
in_mempool: false with block_height โ confirmed in that block
6. Check Block Height
curl -s -X POST $RPC \
-H "Content-Type: application/json" \
-d '{"jsonrpc": "2.0", "method": "get_block_height", "params": {}, "id": 1}'
7. HTLC (Hash-Locked Payment)
An HTLC locks funds so a recipient can claim them by revealing a preimage, or the sender reclaims after a timeout. This is the foundation of trustless atomic swaps and machine-to-machine escrow.
End-to-end workflow
Two agents, A (sender) and B (receiver):
PREIMAGE=$(openssl rand -hex 32)
HASH_LOCK=$(echo -n "$PREIMAGE" | xxd -r -p | shasum -a 256 | cut -d' ' -f1)
echo "Share this hash with Agent A: $HASH_LOCK"
HEIGHT=$(curl -s -X POST $RPC \
-H "Content-Type: application/json" \
-d '{"jsonrpc":"2.0","method":"get_block_height","params":{},"id":1}' \
| python3 -c "import sys,json; print(json.load(sys.stdin)['result']['height'])")
TIMEOUT=$((HEIGHT + 500))
exfer script htlc-lock \
--wallet ~/agent-a.key \
--receiver <AGENT_B_PUBKEY> \
--hash-lock $HASH_LOCK \
--timeout $TIMEOUT \
--amount "10 EXFER" \
--rpc $RPC \
--json
TX_ID="<tx_id from above>"
for i in $(seq 1 60); do
RESULT=$(curl -s -X POST $RPC \
-H "Content-Type: application/json" \
-d "{\"jsonrpc\":\"2.0\",\"method\":\"get_transaction\",\"params\":{\"hash\":\"$TX_ID\"},\"id\":1}")
if echo "$RESULT" | grep -q '"block_height"'; then echo "Lock confirmed"; break; fi
if [ "$i" -eq 60 ]; then echo "ERROR: transaction not confirmed after 10 minutes"; exit 1; fi
sleep 10
done
exfer script htlc-claim \
--wallet ~/agent-b.key \
--tx-id $TX_ID \
--preimage $PREIMAGE \
--sender <AGENT_A_PUBKEY> \
--timeout $TIMEOUT \
--rpc $RPC \
--json
exfer script htlc-reclaim \
--wallet ~/agent-a.key \
--tx-id $TX_ID \
--receiver <AGENT_B_PUBKEY> \
--hash-lock $HASH_LOCK \
--timeout $TIMEOUT \
--rpc $RPC \
--json
Command reference
htlc-lock (sender locks funds)
exfer script htlc-lock \
--wallet ~/my-wallet.key \
--receiver <RECEIVER_PUBKEY_HEX> \
--hash-lock <SHA256_HASH_HEX> \
--timeout <BLOCK_HEIGHT> \
--amount "10 EXFER" \
--rpc $RPC \
--json
Output:
{
"tx_id": "2d3fca9d2cb04de879d0235fab7a279de9bfc7dcbe2d857807416974c648c1f4",
"htlc_output_index": 0,
"amount": 1000000000,
"hash_lock": "2fb68185eeaf951e40aafaf2cdc7007710b9d69bc7663e53c581c9408b0c09e9",
"timeout": 24630,
"submitted": true
}
htlc-claim (receiver reveals preimage)
exfer script htlc-claim \
--wallet ~/receiver-wallet.key \
--tx-id <LOCK_TX_ID> \
--preimage <PREIMAGE_HEX> \
--sender <SENDER_PUBKEY_HEX> \
--timeout <TIMEOUT_HEIGHT> \
--rpc $RPC \
--json
Output:
{
"tx_id": "3d7a1a0625af2815e3f18a08db2eff22ca9fe9e5dda33c228d969ce13d6e8a7c",
"claimed_from": "2d3fca9d2cb04de879d0235fab7a279de9bfc7dcbe2d857807416974c648c1f4",
"amount": 999900000,
"fee": 100000,
"submitted": true
}
htlc-reclaim (sender reclaims after timeout)
exfer script htlc-reclaim \
--wallet ~/my-wallet.key \
--tx-id <LOCK_TX_ID> \
--receiver <RECEIVER_PUBKEY_HEX> \
--hash-lock <HASH_LOCK_HEX> \
--timeout <TIMEOUT_HEIGHT> \
--rpc $RPC \
--json
Output:
{
"tx_id": "b84f8f799dc405eb2c5fe5980e2f1c43b71c15331cc8d035c5a62e8ec8ad0baa",
"reclaimed_from": "933886c612c9de9f4093fb8aa3852f75f4557da2b5987d76e50fde128511f922",
"amount": 999900000,
"fee": 100000,
"submitted": true
}
The command checks that the current block height exceeds the timeout before submitting.
Poll for confirmation (after any transaction)
TX_ID="<tx_id>"
for i in $(seq 1 60); do
RESULT=$(curl -s -X POST $RPC \
-H "Content-Type: application/json" \
-d "{\"jsonrpc\":\"2.0\",\"method\":\"get_transaction\",\"params\":{\"hash\":\"$TX_ID\"},\"id\":1}")
if echo "$RESULT" | grep -q '"block_height"'; then
echo "Confirmed: $RESULT"
break
fi
if [ "$i" -eq 60 ]; then
echo "ERROR: transaction not confirmed after 10 minutes"
exit 1
fi
echo "Pending... ($i/60)"
sleep 10
done
7a. Multisig
Multisig 2-of-2
Both parties must sign to spend. Use for joint custody, payment channels, or atomic two-party agreements.
multisig2of2-lock
exfer script multisig2of2-lock \
--wallet ~/my-wallet.key \
--pubkey-b <OTHER_PUBKEY_HEX> \
--amount "10 EXFER" \
--rpc $RPC \
--json
multisig2of2-spend
exfer script multisig2of2-spend \
--wallet ~/wallet-a.key \
--wallet2 ~/wallet-b.key \
--tx-id <LOCK_TX_ID> \
--to <DESTINATION_ADDRESS_HEX> \
--rpc $RPC \
--json
Multisig 1-of-2
Either party can spend independently. Use for shared accounts or backup access.
multisig1of2-lock
exfer script multisig1of2-lock \
--wallet ~/my-wallet.key \
--pubkey-b <OTHER_PUBKEY_HEX> \
--amount "10 EXFER" \
--rpc $RPC \
--json
multisig1of2-spend
exfer script multisig1of2-spend \
--wallet ~/my-wallet.key \
--tx-id <LOCK_TX_ID> \
--other-pubkey <OTHER_PUBKEY_HEX> \
--path a \
--rpc $RPC \
--json
--path: a if your key was first (pubkey_a at lock time), b if second.
Multisig 2-of-3
Any two of three parties can spend. Use for committee governance or 2FA with recovery.
multisig2of3-lock
exfer script multisig2of3-lock \
--wallet ~/my-wallet.key \
--pubkey-b <PUBKEY_B_HEX> \
--pubkey-c <PUBKEY_C_HEX> \
--amount "10 EXFER" \
--rpc $RPC \
--json
multisig2of3-spend
exfer script multisig2of3-spend \
--wallet ~/signer1.key \
--wallet2 ~/signer2.key \
--tx-id <LOCK_TX_ID> \
--to <DESTINATION_ADDRESS_HEX> \
--pubkey-a <PUBKEY_A_HEX> \
--pubkey-b <PUBKEY_B_HEX> \
--pubkey-c <PUBKEY_C_HEX> \
--path ab \
--rpc $RPC \
--json
--path: ab, ac, or bc โ which pair of keys the two wallets hold.
7b. Vault
Timelock + emergency recovery key. Primary key can spend after locktime. Recovery key can spend anytime (emergency override).
vault-lock
exfer script vault-lock \
--wallet ~/primary-wallet.key \
--recovery-pubkey <RECOVERY_PUBKEY_HEX> \
--locktime <BLOCK_HEIGHT> \
--amount "100 EXFER" \
--rpc $RPC \
--json
vault-spend (primary key, after locktime)
exfer script vault-spend \
--wallet ~/primary-wallet.key \
--tx-id <LOCK_TX_ID> \
--recovery-pubkey <RECOVERY_PUBKEY_HEX> \
--locktime <BLOCK_HEIGHT> \
--rpc $RPC \
--json
Fails if current block height <= locktime.
vault-recover (recovery key, anytime)
exfer script vault-recover \
--wallet ~/recovery-wallet.key \
--tx-id <LOCK_TX_ID> \
--primary-pubkey <PRIMARY_PUBKEY_HEX> \
--locktime <BLOCK_HEIGHT> \
--rpc $RPC \
--json
7c. Escrow
Three-path spending: mutual release, arbiter decision, or timeout refund.
escrow-lock
exfer script escrow-lock \
--wallet ~/party-a.key \
--party-b <PARTY_B_PUBKEY_HEX> \
--arbiter <ARBITER_PUBKEY_HEX> \
--timeout <BLOCK_HEIGHT> \
--amount "50 EXFER" \
--rpc $RPC \
--json
escrow-release (mutual โ both parties sign)
exfer script escrow-release \
--wallet ~/party-a.key \
--wallet2 ~/party-b.key \
--tx-id <LOCK_TX_ID> \
--to <DESTINATION_ADDRESS_HEX> \
--party-a <PARTY_A_PUBKEY_HEX> \
--party-b <PARTY_B_PUBKEY_HEX> \
--arbiter <ARBITER_PUBKEY_HEX> \
--timeout <BLOCK_HEIGHT> \
--rpc $RPC \
--json
escrow-arbitrate (arbiter decides)
exfer script escrow-arbitrate \
--wallet ~/arbiter.key \
--tx-id <LOCK_TX_ID> \
--to <DESTINATION_ADDRESS_HEX> \
--party-a <PARTY_A_PUBKEY_HEX> \
--party-b <PARTY_B_PUBKEY_HEX> \
--timeout <BLOCK_HEIGHT> \
--rpc $RPC \
--json
escrow-reclaim (party A, after timeout)
exfer script escrow-reclaim \
--wallet ~/party-a.key \
--tx-id <LOCK_TX_ID> \
--party-b <PARTY_B_PUBKEY_HEX> \
--arbiter <ARBITER_PUBKEY_HEX> \
--timeout <BLOCK_HEIGHT> \
--rpc $RPC \
--json
Fails if current block height <= timeout.
7d. Delegation
Owner + time-limited delegate. Owner can spend anytime. Delegate can only spend before the expiry height.
delegation-lock
exfer script delegation-lock \
--wallet ~/owner.key \
--delegate <DELEGATE_PUBKEY_HEX> \
--expiry <BLOCK_HEIGHT> \
--amount "10 EXFER" \
--rpc $RPC \
--json
delegation-owner-spend (owner, anytime)
exfer script delegation-owner-spend \
--wallet ~/owner.key \
--tx-id <LOCK_TX_ID> \
--delegate <DELEGATE_PUBKEY_HEX> \
--expiry <BLOCK_HEIGHT> \
--rpc $RPC \
--json
delegation-delegate-spend (delegate, before expiry)
exfer script delegation-delegate-spend \
--wallet ~/delegate.key \
--tx-id <LOCK_TX_ID> \
--owner <OWNER_PUBKEY_HEX> \
--expiry <BLOCK_HEIGHT> \
--rpc $RPC \
--json
Fails if current block height >= expiry.
8. Start Mining
Generate a wallet first if you don't have one (see Section 2):
exfer wallet generate --output ~/exfer-wallet.key --json
Mining with pubkey only (recommended โ no private key on server)
exfer mine \
--datadir ~/.exfer \
--miner-pubkey <YOUR_PUBKEY_HEX> \
--rpc-bind 127.0.0.1:9334 \
--repair-perms
--miner-pubkey: your wallet's public key (from exfer wallet info --json). Coinbase rewards are paid to this key's address. The private key is NOT needed on the mining server.
- Current block reward: ~100 EXFER per block. Reward decreases over time (half-life ~2 years).
- Default seed nodes are built in โ no
--peers needed.
--rpc-bind: optional JSON-RPC endpoint (use 127.0.0.1 for local-only access). RPC has no authentication โ do not bind to 0.0.0.0 on untrusted networks without a reverse proxy.
--repair-perms: auto-fix node identity key permissions
--verify-all: verify PoW for all blocks during startup replay (slow, use only if database integrity is suspect). Also disables assume-valid.
--no-assume-valid: disable assume-valid optimization โ verify Argon2id PoW for all blocks during IBD, even below the hardcoded checkpoint height (130,000). By default, blocks at or below this checkpoint skip PoW verification during initial sync to speed up IBD. All other validation (transactions, signatures, UTXO accounting, state roots) is always performed.
Run in background
Linux:
nohup ./target/release/exfer mine \
--datadir ~/.exfer \
--miner-pubkey <YOUR_PUBKEY_HEX> \
--rpc-bind 127.0.0.1:9334 \
--repair-perms \
> ~/exfer.log 2>&1 &
macOS:
cat > ~/Library/LaunchAgents/org.exfer.miner.plist << EOF
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key><string>org.exfer.miner</string>
<key>ProgramArguments</key>
<array>
<string>$(which exfer || echo ./target/release/exfer)</string>
<string>mine</string>
<string>--datadir</string><string>$HOME/.exfer</string>
<string>--miner-pubkey</string><string>YOUR_PUBKEY_HEX</string>
<string>--repair-perms</string>
</array>
<key>KeepAlive</key><true/>
<key>StandardOutPath</key><string>/tmp/exfer.log</string>
<key>StandardErrorPath</key><string>/tmp/exfer.log</string>
</dict>
</plist>
EOF
launchctl load ~/Library/LaunchAgents/org.exfer.miner.plist
Check status: curl -s http://127.0.0.1:9334 -d '{"jsonrpc":"2.0","id":1,"method":"get_block_height","params":{}}'
Run a non-mining full node
exfer node \
--datadir ~/.exfer \
--rpc-bind 127.0.0.1:9334 \
--repair-perms
RPC Methods
All methods use JSON-RPC 2.0 over HTTP POST.
| Method | Params | Description |
|---|
get_block_height | {} | Current tip height and block ID |
get_balance | {"address": "hex"} | Spendable balance for an address |
get_address_utxos | {"address": "hex"} | List of spendable UTXOs for an address (max 1,000) |
get_script_utxos | {"script_hex": "hex"} | List of spendable UTXOs locked to an exact output script (max 1,000) |
get_block | {"height": u64} or {"hash": "hex"} | Block info including transaction list |
get_transaction | {"hash": "hex"} | Transaction details, mempool status, block height |
send_raw_transaction | {"tx_hex": "hex"} | Submit a serialized signed transaction |
Available Covenant Patterns
| Pattern | CLI | Description |
|---|
| HTLC | htlc-lock, htlc-claim, htlc-reclaim | Hash time-locked contract (atomic swaps) |
| Multisig 2-of-2 | multisig2of2-lock, multisig2of2-spend | Both parties must sign |
| Multisig 1-of-2 | multisig1of2-lock, multisig1of2-spend | Either party can sign |
| Multisig 2-of-3 | multisig2of3-lock, multisig2of3-spend | Any 2 of 3 parties |
| Vault | vault-lock, vault-spend, vault-recover | Timelock + recovery key |
| Escrow | escrow-lock, escrow-release, escrow-arbitrate, escrow-reclaim | Mutual / arbiter / timeout (3-path) |
| Delegation | delegation-lock, delegation-owner-spend, delegation-delegate-spend | Owner + time-limited delegate |
All commands are under exfer script <command>. Use --json for machine-readable output.
Protocol Constants
| Constant | Value |
|---|
| Block time target | 10 seconds |
| Difficulty retarget | Every 4,320 blocks |
| Initial block reward | 100 EXFER |
| Reward half-life | 6,307,200 blocks (~2 years) |
| Minimum reward | 1 EXFER |
| Coinbase maturity | 360 blocks |
| Max block size | 4 MiB |
| Max transaction size | 1 MiB |
| Dust threshold | 200 exfers |
| PoW algorithm | Argon2id (m=64MiB, t=2, p=1) |
| P2P port | 9333 |
| RPC port | 9334 (optional) |