Arkade Sidecar

This sidecar exposes an HTTP API for LNbits to use Arkade for lightning payments.

Docs:

• https://docs.arkadeos.com/
• https://docs.arkadeos.com/llms.txt

Install

npm install

Run

ARKADE_MNEMONIC="bottom bottom bottom bottom bottom bottom bottom bottom bottom bottom bottom bottom" \
ARKADE_ARK_SERVER_URL="https://arkade.computer" \
ARKADE_BOLTZ_SERVER_URL="https://api.ark.boltz.exchange" \
ARKADE_SIDECAR_PORT=8765 \
node server.mjs

Optional API key:

ARKADE_SIDECAR_API_KEY="mykey"

Set the same key in LNbits as ARKADE_L2_API_KEY.

If you prefer to provide the mnemonic after startup, omit ARKADE_MNEMONIC and POST it to the sidecar:

curl -X POST http://127.0.0.1:8765/v1/mnemonic \
  -H "Content-Type: application/json" \
  -d '{"mnemonic":"bottom bottom bottom bottom bottom bottom bottom bottom bottom bottom bottom bottom"}'

Endpoints

• POST /v1/mnemonic
• POST /v1/balance
• POST /v1/invoices
• POST /v1/payments
• GET /v1/invoices/stream
• GET /v1/invoices/{id}
• GET /v1/payments/{id}
• GET /health

Environment variables

Variable	Default	Description
ARKADE_MNEMONIC	—	12-word BIP39 mnemonic
ARKADE_IS_MAINNET	auto	Set to false for non-mainnet wallets
ARKADE_NETWORK	mainnet	Optional network hint for Boltz selection
ARKADE_ARK_SERVER_URL	https://arkade.computer	Arkade operator URL
ARKADE_BOLTZ_SERVER_URL	https://api.ark.boltz.exchange	Boltz API URL
ARKADE_BOLTZ_NETWORK	derived	Override Boltz network name
ARKADE_SIDECAR_HOST	127.0.0.1	Listen host
ARKADE_SIDECAR_PORT	8765	Listen port
ARKADE_SIDECAR_API_KEY	—	Optional x-api-key header value
ARKADE_SIDECAR_STATE_PATH	./arkade-sidecar-state.json	Persisted payment/invoice state
ARKADE_STORAGE_PATH	./arkade-wallet.sqlite	Wallet SQLite database path
ARKADE_SWAP_STORAGE_PATH	./arkade-swaps.sqlite	Swap repository storage path
ARKADE_PAY_TIMEOUT_MS	30000	Timeout for synchronous Lightning sends
ARKADE_STREAM_KEEPALIVE_MS	15000	SSE keepalive comment interval
ARKADE_STREAM_HEARTBEAT_MS	30000	SSE heartbeat interval
ARKADE_STATE_PERSIST_DEBOUNCE_MS	1000	State persistence debounce
ARKADE_CORS_ALLOW_ORIGIN	—	Optional allowed browser origin
ARKADE_CORS_ALLOW_HEADERS	Content-Type, x-api-key	Allowed CORS request headers
ARKADE_CORS_ALLOW_METHODS	GET, POST, OPTIONS	Allowed CORS methods

Notes

• The HTTP API mirrors the Spark sidecar shape so LNbits can use the same balance, invoice, payment, and stream flows.
• Lightning receive invoices are monitored in the background and emitted on the SSE stream once claimed into the Arkade wallet.
• Payment and invoice lookup endpoints are backed by local persisted state so LNbits can poll by checking_id.