lattice.json reference

lattice up turns each key into a lattice-node flag. Any key not listed here is rejected with unknown lattice.json key(s): ….

Key	Type	Node flag	Default	Validation / notes
listen	port	--listen-port	4001 (written by init)	nonzero, unique
rpc	port	--rpc-port	8080 (written by init)	nonzero, unique; always loopback
webSocket	port	--websocket-port	the node tries 4002 and continues without it if the bind fails	0 = off; if set explicitly, a failed bind is fatal
peers	array, or object keyed by chain path	--peer / --no-default-peers / --chain-peer P=peer	built-in Nexus seeds	every object key must be a hosted chain
externalAddress	host (no port)	--external-address	none	set when the observed address isn’t dialable
publicRead	port	--public-read-port	off	nonzero, unique; binds 0.0.0.0
publicReadRate	req/s	--public-read-rate	25	per client; 0 = no per-client cap
publicReadExpensiveRate	req/s	--public-read-expensive-rate	1	per client, for expensive routes
publicReadMaxRate	req/s	--public-read-max-rate	200	for the whole listener
publicReadFetches	int	--public-read-fetches	4	concurrent peer fetches on a miss; 0 = serve only content the node holds
publicReadURL	URL	--public-read-url	none	absolute http(s), no credentials, query or fragment
publicSubmit	bool	--public-submit	false	requires publicRead
publicSubmitRate	req/s	--public-submit-rate	10	for the whole listener
minRelayFee	uint64	--min-relay-fee	0	relay policy, not consensus
servingMaxConcurrent	int	--serving-max-concurrent	64	content-serving concurrency for peers
servingMaxInFlightVolumeBytes	int	--serving-max-in-flight-volume-bytes	Ivy default
blockBodies	"all" / "none"	--block-bodies	all	none prunes at the next start
state	"all" / "tip" / "none"	--state	all
announceLifetime	seconds	--announce-lifetime	1200	1…86400; DHT provider record lifetime
hostedChains	[path]	--host-chain P[=spec]	none	Nexus-rooted, each parent before its children, no duplicates
rpcAllowedOrigins	[origin]	--rpc-allowed-origin	none (browsers refused)	e.g. chrome-extension://<id>; the cookie is still required
mine	object	used only by lattice mine	none	see below

peers

"peers": ["<pubkey>@a.example.org:4001", "<pubkey>@b.example.org:4001"]   // Nexus list; replaces the seeds
"peers": []                                                                // connect to no one (inbound only)
"peers": { "Nexus": ["…"], "Nexus/Alpha": ["<pubkey>@c.example.org:4001"] } // per-chain seeds

A peer string is <pubkey>@host:port, the output of lattice identity. When a chain has fewer than 8 peers (--peer-target), or has stalled, the node dials remembered peers (peers.json, advisory, safe to delete). For child chains it also searches the DHT rendezvous. Below 2 peers (--peers-before-seeds) it dials the seeds.

mine

"mine": {
  "worker": "cpu",
  "workers": 2,
  "batchSize": 2000000000,
  "recipients": { "Nexus": "<address>", "Nexus/Alpha": "<address>" },
  "minWork": { "Nexus": "2^32" },
  "minBlockIntervalSeconds": 10,
  "templateTimeoutSeconds": 60,
  "roundDeadlineMultiplier": 10
}

Key	Default	Meaning
worker	cpu	cpu = the bundled lattice-miner; otherwise a path to a worker executable
workers	1	parallel worker processes
batchSize	2,000,000,000	total nonces searched per round
recipients	none	address for each chain. A chain left out burns its reward and fees.
minWork	none	local search filter, 2^N or a decimal. Not consensus.
minBlockIntervalSeconds	none	minimum spacing between parent template builds
templateTimeoutSeconds	60	1…60
roundDeadlineMultiplier	10	≥1; headroom on the round deadline

Every chain named in recipients or minWork must be hosted. The retired keys mine.chain and mine.rewards are rejected.

Daemon-only flags (no lattice.json key)

--rpc-bind (loopback values only), --rpc-cookie-file, --peer-target (8), --peers-before-seeds (2), --minimum-peer-key-bits (0), --overlay-max-connections-per-netgroup, --peer-search-interval (600 s; 0 turns search off, for isolated nodes only).

Environment variables

Var	Effect
LATTICE_SYNC_TRACE=1	Sync and acquisition traces to stderr (that is, log/lattice-node.log). Any other non-empty value is a file path. Produces a lot of output, so use it only while diagnosing.
LATTICE_SYNC_TRACE_MAX_BYTES	Size cap for the trace file (default 64 MiB).
LATTICE_FORBID_DEFAULT_PEERS=1	Refuse to start on the built-in seeds. Use it in tests or CI so they never join the public network.

The CLI itself reads no environment variables.

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Source: lattice-skills/skills/lattice-node-operator/references/lattice-json.md at 21a7fca17116