XChain Platform Indexer — Configuration Reference

Environment Variables

Configuration is loaded from a .env file and environment variables. Copy the .env.example file and configure before running.

Required Variables

Variable	Description	Example
`DECODER_DB_HOST`	Decoder database hostname	`localhost`
`DECODER_DB_PORT`	Decoder database port	`3306`
`DECODER_DB_NAME`	Decoder database name	`XChain_BTC_Mainnet_Decoder`
`DECODER_DB_USER`	Decoder database username	`xchain`
`DECODER_DB_PASS`	Decoder database password	`secretpassword`
`INDEXER_DB_HOST`	Indexer database hostname	`localhost`
`INDEXER_DB_PORT`	Indexer database port	`3306`
`INDEXER_DB_NAME`	Indexer database name	`XChain_BTC_Mainnet_Indexer`
`INDEXER_DB_USER`	Indexer database username	`xchain`
`INDEXER_DB_PASS`	Indexer database password	`secretpassword`
`INDEXER_API_PORT`	API server listening port	`3000`
`INDEXER_COIN`	Blockchain to index	`BTC`, `LTC`, or `DOGE`
`INDEXER_NETWORK`	Network to index	`mainnet`, `testnet`, or `regtest`

Optional Variables

Variable	Description	Default
`CORS_ORIGIN`	Allowed CORS origin for API requests	`http://localhost`

Coin-Specific Configuration

Each supported blockchain has a configuration file at src/configs/<COIN>.js (BTC.js, LTC.js, DOGE.js) that defines:

Parameter	Description	Example (BTC)
`ISSUANCE_FEE_TOKEN`	XCHAIN fee for token issuance	`1.00000000`
`ISSUANCE_FEE_SUBTOKEN`	XCHAIN fee for sub-token issuance	`0.50000000`
`EXPIRATION_FEE_DEFAULT_DAYS`	Default listing duration	`90` (3 months)
`EXPIRATION_FEE_FREE_DAYS`	Free listing duration	`182` (6 months)
`EXPIRATION_FEE_PER_DAY`	XCHAIN fee per day beyond free period	`0.00547945`
`ADDRESS.BURN`	Burn address (per network)	`1Muhahahahhahahahahahhahahauxh9QX`
`ADDRESS.GAS`	Gas token issuer address (per network)	`1BTNSGASK5En7rFurDJ79LQ8CVYo2ecLC8`
`ADDRESS.DONATE1`	Protocol development donation address	`1BTNSGASK5En7rFurDJ79LQ8CVYo2ecLC8`
`ADDRESS.DONATE2`	Community development donation address	`1BTNSGASK5En7rFurDJ79LQ8CVYo2ecLC8`
`ADDRESS.FEE_DESTINATION`	Native-coin fee collection address (per network). Overridable at runtime via the `XCHAIN_FEE_DESTINATION_<COIN>_<NETWORK>` env var (e.g. `XCHAIN_FEE_DESTINATION_BTC_REGTEST`); falls back to the placeholder when unset, which disables native-coin fee payment.	(set pre-launch)
`ADDRESS.REWARD`	Validator reward pool — pre-funded, manually topped up, drained by `COLLECT` (BTC only; XCHAIN/COLLECT do not exist on LTC/DOGE, where the slot is unused)	(set pre-launch)

Unified Gas Fee Schedule

After the activation block, fees for VM and staking actions are calculated using a gas-based schedule rather than the legacy flat fee constants. The following parameters are defined in each coin config file (src/configs/<COIN>.js) and are only applied to blocks at or after the activation height:

Parameter	Description	Example (BTC)
`GAS_PRICE`	Base XCHAIN cost per unit of gas	`0.00000001`
`GAS_SCHEDULE`	Object mapping action types to their gas cost in gas units	`{ DEPLOY: 100000, EXECUTE: 10000, STAKE: 5000, ... }`
`UNIFIED_EXPIRATION_FEE_FREE_DAYS`	Free listing duration under the unified schedule (replaces `EXPIRATION_FEE_FREE_DAYS` post-activation)	`365`
`FEE_PAYMENT_MODE`	Reserved key indicating intended fee denomination per chain (`'xchain'` on BTC, `'native'` on LTC/DOGE). Not currently read at runtime — see note below.	`'xchain'` (BTC)

Note on FEE_PAYMENT_MODE: This key is currently informational only and is not read by the fee-processing code. Fee payment mode is detected implicitly at runtime by detectFeePaymentMode() in src/utility.js, which derives the mode from the transaction itself: if a native-coin fee output to the configured fee destination is present it returns 'native'; if absent it returns 'xchain' on BTC (XCHAIN balance deduction is allowed as a fallback) and 'rejected' on LTC/DOGE (native coin is the only accepted fee on those chains). The FEE_PAYMENT_MODE config value is reserved for a future change that makes this detection explicit/config-driven; until then its value must mirror the implicit per-chain behavior to avoid surprising a later refactor.

The legacy flat fee constants (ISSUANCE_FEE_TOKEN, ISSUANCE_FEE_SUBTOKEN, EXPIRATION_FEE_PER_DAY, EXPIRATION_FEE_FREE_DAYS) remain in the coin config files and continue to apply for blocks before the activation height.

Indexer Constants

These values are defined in src/config.js and apply to all chains:

Token Rules

Parameter	Value	Description
`GAS`	`XCHAIN`	Gas token ticker name
`NATIVE_TICK_DECIMALS`	`8`	Decimal places for native coin amounts
`MIN_TICK_LENGTH`	`1`	Minimum ticker name length
`MAX_TICK_LENGTH`	`250`	Maximum ticker name length
`TICK_CHARACTERS`	`a-zA-Z0-9~!@#$%^&*()_+-={}[]:<>.?`	Allowed characters in ticker names
`RESERVED_TICKS`	`['BTC','LTC','DOGE','XCHAIN']`	Ticker names reserved by the protocol
`MIN_TOKEN_DECIMALS`	`0`	Minimum token decimal places
`MAX_TOKEN_DECIMALS`	`18`	Maximum token decimal places
`MIN_TOKEN_SUPPLY`	`0.000000000000000001`	Minimum token supply (10^-18)
`MAX_TOKEN_SUPPLY`	`1000000000000000000000`	Maximum token supply (10^21)

COINPay

Parameter	Value	Description
`COIN_DECIMALS`	`8`	Native coin decimal places (BTC/LTC/DOGE all use 8)
`COINPAY_EXPIRATION`	`7200`	COINPay obligation expiration in seconds (2 hours)

Field Limits

Parameter	Value	Description
`MAX_TOKEN_DESCRIPTION`	`250`	Maximum description length in characters
`MAX_MEMO_LENGTH`	`250`	Maximum memo length in characters
`MAX_FILE_NAME_LENGTH`	`250`	Maximum file name length
`MAX_FILE_TYPE_LENGTH`	`255`	Maximum MIME type length (per RFC 4288)
`MAX_FILE_TITLE_LENGTH`	`250`	Maximum file title length
`MAX_BROADCAST_MESSAGE_LENGTH`	`250`	Maximum broadcast message length
`MAX_BROADCAST_VALUE_LENGTH`	`25`	Maximum broadcast value length
`MAX_MESSAGE_LENGTH`	`1048576`	Maximum message content (1 MB)
`MAX_MESSAGE_KEY_LENGTH`	`1048576`	Maximum encryption key length (1 MB)
`MAX_DISPENSES`	`1000`	Maximum dispenses per dispenser

Timing and Delays

Parameter	Value	Description
`BLOCK_CHECK_INTERVAL`	`5000`	Milliseconds between block polling cycles
`BLOCK_PROCESS_TIMEOUT`	`300000`	Maximum milliseconds to process a single block
`DISPENSER_LIST_DELAY`	`3600`	Seconds before dispenser list updates take effect
`DISPENSER_CLOSE_DELAY`	`3600`	Seconds before dispenser close takes effect

Protocol Constants

Parameter	Value	Description
`MESSAGE_ENCRYPTION_METHODS`	`[1, 2]`	1 = ECDH, 2 = AES
`SLEEP_IMMEDIATE_METHODS`	`[-1, 0]`	-1 = sleep indefinitely, 0 = resume immediately

Based on XChain Platform by Dankest, LLC – https://dankest.llc

Licensed under the GNU Affero General Public License v3.0 (AGPL-3.0-or-later) with a commercial license available for proprietary use.

You may use, modify, and distribute this material under the terms of the License. See LICENSE and NOTICE for full terms. See the licensing overview.