Field notes
glnc field notes
Building a blockchain inspection CLI in public. Decoder edge cases, RPC fallback strategy, the parts of Etherscan we are happy not to rebuild.
Monitor a wallet balance in GitHub Actions, no API key
A scheduled GitHub Actions workflow that checks any wallet balance on a cron, with no API key and no secret to store on the runner. Install glnc, run one command, and gate the job on data quality or a balance threshold with jq.
Designing a stable, versioned JSON envelope for a CLI (and why --watch emits NDJSON)
Pretty human output is not an API contract. glnc wraps every --json line in one envelope (schema, ts, ok, data, error, meta), switches to NDJSON under --watch, keeps stdout data-only, and ships a meta.partial honesty flag plus a glnc schema command so consumers can validate the stream they parse.
Check any Bitcoin address balance, no full node needed
bitcoin-cli only answers for addresses your own node already watches, which means a full sync plus a rescan. glnc reads any Bitcoin address from the terminal in one command, with no node, no account, and no API key, via the Blockstream Esplora API.
Check all wallet tokens across 9 chains in the terminal
Run glnc balance on any address and get a per-token table with USD totals across all 9 chains in one line. Address auto-detection, roughly 1,400-token discovery per EVM chain, every SPL token on Solana, and an honest read of what the totals do and do not include.
Monitor an Ethereum wallet and ping Slack when the balance drops, from the terminal
Wire glnc into a Slack incoming webhook so an on-call engineer learns about a balance change from the same channel that already pages them. One liner, then a script, then a script that does not lie when the data is degraded.
Decoding MultiSend and Governor calldata, from the terminal
A note about the part of glnc that walks Governor, Timelock, MultiSend, and leaf calls without giving up at the first bytes field. The depth-3 cap, the packed-byte parser, and the things still missing.
Why I built a CLI alternative to Etherscan
Twelve Etherscan tabs, no API key, and a working terminal. The story behind glnc, an open-source CLI for blockchain inspection, told the way the README would tell it if it had room to talk.