Relay environment variables

Configuration for the relay, its keeper and the indexer.

The relay and the indexer are two processes from one image and read the same variables. Config is checked at start and a bad value names the variable.

Chains

One relay serves every chain. The flat RPC_URL, CHAIN_ID, REACTOR, VALIDATION, EXECUTOR, FEE_CONTROLLER, KEEPER_PRIVATE_KEY and TOKENS variables describe a single EVM chain and are used when CHAINS is empty. CHAINS is a JSON array describing any number, and wins where both exist.

An EVM entry ("kind": "evm" may be left out):

[{"chainId":8453,"name":"Base","rpcUrls":["https://..."],"reactor":"0x..","validation":"0x..",
  "executor":"0x..","feeController":"0x..","tokens":[{"symbol":"cNGN","address":"0x..","decimals":6,"minimum":"1000"}],
  "gasFeeToken":"0x..","oracle":{"base":"cNGN","quote":"USDC"},"indexerStartBlock":"46676667"}]

A Solana entry. Its keeper secret is SOLANA_KEEPER_SECRET_<chainId>, never in CHAINS:

{"kind":"solana","chainId":103,"cluster":"devnet","rpcUrls":["https://..."],"program":"<base58>","treasury":"<base58>",
 "tokens":[{"symbol":"USDC","address":"<mint>","tokenProgram":"Tokenkeg..","decimals":6}, ...],"feeToken":["USDC","USDT"],
 "pairs":[["cNGN","USDC"],["cNGN","USDT"]],"oracle":{"base":"cNGN","quote":["USDC","USDT"]},
 "feeBps":5,"computeUnitLimit":200000,"computeUnitPrice":"10000","indexerStartSlot":"497711080"}

feeToken and oracle.quote also take one symbol. Without pairs, every pair of tokens with a fee token is a corridor. A token’s minimum is the corridor’s smallest sell amount in whole tokens.

Relay

Variable	Default	Meaning
HOST, PORT	127.0.0.1, 8080
LOG_LEVEL	info
DATABASE_URL	required	Postgres
RPC_FALLBACK_URLS		Comma-separated, tried in order when the primary errors
CHAIN_NAME		Display name for the single chain
PERMIT2	canonical
RFQ_WINDOW_MS	1500	How long resolvers have to reply
QUOTE_TTL_MS	20000	How long a quote stays open
MIN_OFFER_TTL_MS	10000	Offers with a shorter deadline are rejected
HEARTBEAT_INTERVAL_MS, NODE_STALE_MS	10000, 35000
GAS_FEE_TOKEN	buy token	The token the gas fee is charged in
GAS_FEE_FIXED	0	Fallback gas fee in base units when no price is available
GAS_UNITS	450000	Gas one settlement is expected to use
GAS_MARGIN_BPS	2500	Headroom over the estimate (1.25x)
GAS_MIN_USD, GAS_MAX_USD	0.03, 0.5	Floor and ceiling of the gas line
KEEPER_LEASE_TTL_MS	15000	The Postgres lease the keeper leader holds, per chain
STATIC_DIR		Static files served at / (the M0 swap page)
TRUST_PROXY	true	Read the client IP from X-Forwarded-For

Abuse controls and registry

Variable	Default	Meaning
REQUIRE_TAKER_PROOF	false	Require a taker proof on every quote
REQUIRE_REGISTRATION	false	Admit only registered resolvers
MAX_OUTSTANDING_RFQS	4	In-flight RFQs per taker
RESOLVER_RFQ_PER_SEC	100	RFQs per second to any one resolver; burst is twice
RATE_LIMIT_QUOTES_PER_MIN	120	Per IP; 0 disables
RATE_LIMIT_EXECUTIONS_PER_MIN	30
RATE_LIMIT_REGISTER_PER_MIN	10

Oracle

Variable	Default	Meaning
ORACLE_ENABLED	true
ORACLE_INTERVAL_MS	10000
ORACLE_BASE, ORACLE_QUOTE	cNGN, USDC	Symbols of the band. ORACLE_QUOTE may list several dollar tokens, comma-separated; the first prices the gas fee
ORACLE_STATIC		A fixed NGN/USD value instead of the public sources
ORACLE_STATIC_SOL_USD		A fixed SOL/USD price for the Solana gas fee
ORACLE_SOURCES		Which sources make the band. Empty means the peer-to-peer and NGN exchange books; official FX rates can be added by name

Limit orders

Variable	Default	Meaning
LIMIT_ORDERS_ENABLED	true
LIMIT_POLL_MS	5000	How often the keeper leader looks at the book
LIMIT_RECHECK_MS	15000	Least time between two auctions for one order; doubles after each failed fill
LIMIT_MAX_PER_TICK	8	Auctions per poll per chain
LIMIT_BAND_SLACK_BPS	150	An order more than this much better than the oracle mid is not auctioned
LIMIT_MIN_EXPIRY_S, LIMIT_MAX_EXPIRY_S	300, 2592000	5 minutes to 30 days
LIMIT_MAX_OPEN_PER_TAKER	20
LIMIT_GAS_HEADROOM	3	The gas cap an order signs, as a multiple of today’s fee

Remote console

Variable	Default	Meaning
REMOTE_ENABLED	true
REMOTE_MAX_DEVICES	8	Device sockets per channel
REMOTE_DEVICE_CONNS_PER_IP	20
REMOTE_ALLOWED_ORIGINS		Comma-separated origins that may open a device socket; empty allows every origin

Indexer

Variable	Default	Meaning
HOST, PORT	0.0.0.0, 8090	/health reports lag in blocks or slots
DATABASE_URL	required
CHAINS		The same value the relay reads
INDEXER_START_BLOCK	0	First block scanned on an empty database (single-chain form)
INDEXER_CONFIRMATIONS	12
INDEXER_POLL_MS	4000
INDEXER_CHUNK	2000	Blocks per getLogs call
RELIABILITY_EVERY_MS	60000	How often reliability and demotion are recomputed