heartbeat-tx

Overview ¶

heartbeat-tx submits one zero-value self-transfer EVM transaction per configured chain. Etna's "empty-block-production-off" feature only seals EVM blocks when a transaction arrives, so a single tx is enough to advance `eth_blockNumber` past 0x0 and prove the chain is alive.

Designed to run from a Kubernetes CronJob:

heartbeat-tx \
  --chains=C,hanzo,zoo,pars,spc \
  --rpc-base=https://api.lux-test.network \
  --mnemonic-env=LUX_MNEMONIC \
  --bip44-idx=10

EVM keys are derived at BIP44 m/44'/60'/0'/0/<idx> (Ethereum coin type 60). Index 10 is reserved for heartbeats — validators occupy 0-4 and subnet control keys occupy 5-7.

One failed chain does not abort the run; each chain reports its own error. Exit code 0 if every chain accepted its tx, 1 otherwise.