# #280 tx_from + gas price on v4tape swaps and liq
Host research-box. Files /opt/sw/v4tape/swaps.jsonl and liq.jsonl (mirrors a1pull@v4swaps / @v4liq on main). All classes (A1 and H3000), forward only from 20:46 UTC 9 Oct 2026 (13:46 10 Oct BKK 03:46); older rows lack the keys. No backfill.
New keys per row: tx_from (EOA that sent the tx), gas_price (wei, effective price from eth_getTransactionByHash), priority_fee (wei, maxPriorityFeePerGas, null if legacy tx). null = RPC lookup failed.
Example: jq 'select(.tx_from!=null)|[.tx_from,.gas_price]' /opt/sw/v4tape/swaps.jsonl
Cost: one batched getTransactionByHash per 20 txs, free providers. Backup v4tape.py.bak-280. Restart resumes from hb block (no gap).
Note: for pull (burn) txs match liq.jsonl rows by tx. pools.jsonl already has tx_from (#243).