blockbook/docs/env.md

Environment variables

Some behavior of Blockbook can be modified by environment variables. The variables usually start with a coin shortcut to allow to run multiple Blockbooks on a single server.

• <coin shortcut>_WS_GETACCOUNTINFO_LIMIT - Limits the number of getAccountInfo requests per websocket connection to reduce server abuse. Accepts number as input.

• <coin shortcut>_WS_ALLOWED_ORIGINS - Comma-separated list of allowed WebSocket origins (e.g. https://example.com, http://localhost:3000). If omitted, all origins are allowed and it is the operator's responsibility to enforce origin access (for example via proxy).

• <coin shortcut>_STAKING_POOL_CONTRACT - The pool name and contract used for Ethereum staking. The format of the variable is <pool name>/<pool contract>. If missing, staking support is disabled.

• COINGECKO_API_KEY, <network>_COINGECKO_API_KEY, or <coin shortcut>_COINGECKO_API_KEY - API key for making requests to CoinGecko in the paid tier. If any of these variables is set, it must be non-empty (empty value is treated as a configuration error and Blockbook fails on startup). Lookup priority is:

  1. <network>_COINGECKO_API_KEY
  2. <coin shortcut>_COINGECKO_API_KEY
  3. COINGECKO_API_KEY Example: for Optimism, network=OP and coin shortcut=ETH, so OP_COINGECKO_API_KEY is preferred over ETH_COINGECKO_API_KEY.

• <coin shortcut>_ALLOWED_RPC_CALL_TO - Addresses to which rpcCall websocket requests can be made, as a comma-separated list. If omitted, rpcCall is enabled for all addresses.

Build-time variables

• BB_RPC_URL_HTTP_<coin alias> - Overrides ipc.rpc_url_template during package/config generation so build and integration-test tooling can target hosted HTTP RPC endpoints without editing coin JSON.
• BB_RPC_URL_WS_<coin alias> - Overrides ipc.rpc_url_ws_template for WebSocket subscriptions; should point to the same host as BB_RPC_URL_HTTP_<coin alias>.
• BB_RPC_BIND_HOST_<coin alias> - Overrides backend RPC bind host during package/config generation; when set to 0.0.0.0, RPC stays restricted unless BB_RPC_ALLOW_IP_<coin alias> is set.
• BB_RPC_ALLOW_IP_<coin alias> - Overrides backend RPC allow list for UTXO configs (e.g. rpcallowip), defaulting to 127.0.0.1.