Configuration

# Override network setting
export BARK_SERVER__NETWORK=signet

# Override database password
export BARK_SERVER__POSTGRES__PASSWORD=newpassword

# Override Bitcoin RPC URL
export BARK_SERVER__BITCOIND__URL=http://127.0.0.1:38332

# Directory for wallet state and mnemonic
data_dir = "./bark-server"

# Bitcoin network to operate on
network = "signet"  # "mainnet" | "testnet" | "signet" | "regtest"

# VTXO lifetime in blocks (default: 4320 ≈ 30 days)
vtxo_lifetime = 4320

# Blocks between each VTXO exit clause (default: 144 ≈ 1 day)
vtxo_exit_delta = 144

# Maximum VTXO amount (optional)
# max_vtxo_amount = "1000000 sat"

# Minimum board (onchain onboarding) amount
min_board_amount = "20000 sat"

# Maximum arkoor (off-chain transfer) depth
max_arkoor_depth = 5

# Maximum arkoor outputs per input
max_arkoor_fanout = 4

# Board transaction confirmations before accepting VTXO
required_board_confirmations = 3

# Confirmations for untrusted round inputs
round_tx_untrusted_input_confirmations = 2

# Time between rounds
round_interval = "10s"

# Time for users to submit payments
round_submit_time = "2s"

# Time for users to sign VTXO tree
round_sign_time = "2s"

# Number of cosign nonces required per user
# Limits maximum VTXO tree size: max_vtxos = 4^nb_round_nonces
nb_round_nonces = 8  # = 4^8 = 65,536 max VTXOs per round

# Timeout for forfeit nonce storage
round_forfeit_nonces_timeout = "30s"

[rpc]
# Public Ark API (required)
public_address = "127.0.0.1:3535"

# Admin API (optional but recommended)
admin_address = "127.0.0.1:3536"

# Integration manager API (optional)
integration_address = "127.0.0.1:3537"

# Include full stack traces in RPC errors (disable in production)
rpc_rich_errors = true

[postgres]
host = "localhost"
port = 5432
name = "bark-server-db"
user = "postgres"
password = "super_secure"
max_connections = 10

[bitcoind]
url = "http://127.0.0.1:18443"  # RPC endpoint

# Authentication: Use ONE of the following methods

# Option 1: Cookie file
cookie = "/home/bitcoin/.bitcoin/.cookie"

# Option 2: Username/password
# rpc_user = "admin"
# rpc_pass = "super_secure"

# CLN node reconnection interval
cln_reconnect_interval = "10s"

# Invoice checking intervals
invoice_check_interval = "3s"
invoice_recheck_delay = "2s"
invoice_check_base_delay = "10s"
max_invoice_check_delay = "10m"
invoice_poll_interval = "30s"

# TrackAll stream reconnection backoff
track_all_base_delay = "1s"
max_track_all_delay = "60s"

# HTLC timing
htlc_expiry_delta = 40  # blocks between LN and Ark HTLC expiries
htlc_send_expiry_delta = 258  # blocks for HTLC-send VTXO expiry
max_user_invoice_cltv_delta = 250

# Invoice expiry
invoice_expiry = "48h"

# Timeout for user to claim received payments
receive_htlc_forward_timeout = "30s"

# Require proof for lightning receives (anti-DoS)
ln_receive_anti_dos_required = false

[[cln_array]]
uri = "http://127.0.0.1:8000"
priority = 10  # Lower number = higher priority
server_cert_path = "/etc/cln/server.cert"
client_cert_path = "/etc/cln/client.cert"
client_key_path = "/etc/cln/client.key"

# Optional: Hold invoice plugin configuration
[cln_array.hold_invoice]
uri = "http://127.0.0.1:8001"
server_cert_path = "/etc/cln/hold/server.cert"
client_cert_path = "/etc/cln/hold/client.cert"
client_key_path = "/etc/cln/hold/client.key"

# Add more nodes as needed
[[cln_array]]
uri = "http://127.0.0.1:9000"
priority = 20
# ... (same cert configuration)

[fees.board]
min_fee_sat = 330  # Minimum fee (can be dust)
base_fee_sat = 100  # Base fee
ppm = 1000  # Parts per million (0.1%)

[fees.offboard]
base_fee_sat = 200
fixed_additional_vb = 212  # Virtual bytes to charge (covers tx size)

# Expiry-based PPM tiers
ppm_expiry_table = [
    { expiry_blocks_threshold = 0, ppm = 0 },       # ≤96 blocks: 0%
    { expiry_blocks_threshold = 97, ppm = 1000 },   # 97-198: 0.1%
    { expiry_blocks_threshold = 199, ppm = 4000 },  # 199-2160: 0.4%
    { expiry_blocks_threshold = 2161, ppm = 8000 }, # >2160: 0.8%
]

[fees.refresh]
base_fee_sat = 150
ppm_expiry_table = [
    { expiry_blocks_threshold = 0, ppm = 0 },
    { expiry_blocks_threshold = 97, ppm = 1000 },
    { expiry_blocks_threshold = 199, ppm = 4000 },
    { expiry_blocks_threshold = 2161, ppm = 8000 },
]

# Lightning receive fees
[fees.lightning_receive]
base_fee_sat = 100
ppm = 2000  # 0.2%

# Lightning send fees
[fees.lightning_send]
min_fee_sat = 10
base_fee_sat = 75
ppm_expiry_table = [
    { expiry_blocks_threshold = 0, ppm = 0 },
    { expiry_blocks_threshold = 97, ppm = 1000 },
    { expiry_blocks_threshold = 199, ppm = 4000 },
    { expiry_blocks_threshold = 2161, ppm = 8000 },
]

# Feerate for offboard transactions
offboard_feerate = "7sat/vb"

# Offboard session timeout
offboard_session_timeout = "30s"

[vtxopool]
# Target VTXO denominations and counts
vtxo_targets = [
    "1000sat:10",   # Maintain 10 VTXOs of 1000 sats
    "10000sat:10"   # Maintain 10 VTXOs of 10000 sats
]

# Issue new VTXOs when pool falls below this % of target
vtxo_target_issue_threshold = 80

# Pool VTXO lifetime in blocks
vtxo_lifetime = 432

# Don't use VTXOs this close to expiry
vtxo_pre_expiry = 144

# Maximum depth for pool VTXOs
max_vtxo_arkoor_depth = 3

# How often to check if issuance is needed
issue_interval = "1m"

[watchman]
enabled = true  # Enable forfeit watcher
process_interval = "60s"  # How often to check for forfeits
progress_grace_period = 2  # Blocks before deadline to progress
claim_chunksize = 20  # Max VTXOs to claim per transaction
incremental_relay_fee = "100 sat/kvb"
min_cpfp_amount = "10000 sat"  # Minimum for CPFP fee bumping

# Minimum balance for watchman wallet
watchman_min_balance = "1 btc"

[fee_estimator]
update_interval = "1m"  # Poll bitcoind for fee estimates

# Fallback rates when estimator unavailable
fallback_fee_rate_fast = "25sat/vb"     # 1 block target
fallback_fee_rate_regular = "10sat/vb"  # 3 block target
fallback_fee_rate_slow = "4sat/vb"      # 6 block target

# TX index check interval
txindex_check_interval = "30s"

# Block polling interval
sync_manager_block_poll_interval = "100ms"

# Transaction rebroadcast interval
transaction_rebroadcast_interval = "1m"

# Maximum items returned per mailbox query
max_read_mailbox_items = 100

# Optional message sent to clients on handshake
# handshake_psa = "Welcome to our Ark Server!"

# OpenTelemetry collector endpoint (optional)
# otel_collector_endpoint = "http://127.0.0.1:4000"

# Tracing sample rate: 0.0-1.0 (0=disabled, 1=all traces)
# otel_tracing_sampler = "0.5"

# Deployment name for metrics
otel_deployment_name = "my_regtest"

captaind -C /path/to/config.toml start