mempool·watch

A browser-native view of the Bitcoin mempool — the third sibling, after block·health and fork·watch.

The mempool is different from everything the other two sites watch: it has no proof-of-work, so it cannot be verified — only witnessed. This page is built around that honesty:

1. Witnesses are compared, not trusted. Pending-tx counts, sizes and fees from independent public sources (mempool.space, blockstream.info) side by side, with drift surfaced.
2. Bytes are verified where bytes exist. Every transaction the page inspects is fetched raw and re-hashed — a claimed txid whose bytes don't match is flagged, not displayed as fact. Incoming OP_RETURN datacarrier is classified against the historical 80/83-byte standard.
3. Consensus settles the argument. The one thing a mempool view can be checked against is the chain itself: every mined block's txids are compared with the public mempool view that preceded it. Transactions mined without ever appearing publicly are dark transactions — the signature of out-of-band submission — tallied per pool, from your own observations.

Dark-transaction method (and its limits)

A full txid snapshot of the public mempool is taken every 2 minutes (~3–5 MB, toggleable), merged with a live sample stream. When a block arrives, its txids (coinbase excluded) are checked against everything seen before it. The result is an upper bound: a tx broadcast in the final seconds before its block counts as unseen. Blocks arriving with a stale baseline are recorded without a measurement rather than guessed at. The per-pool table needs days of watching before percentages mean much — it is a sample from your browser, not a census.

Roadmap

• WS-to-TCP bridge to a real node — the vendored engine already carries the P2P codec (engine/codec/p2p.js, ws.js); pointing the page at a user-supplied bridge (config-only, like the siblings' ?peer= links — never a server in the repo) gives an independent mempool witness instead of explorer APIs, and real-time tx arrival.
• Cross-correlation with fork·watch's miner league: pools' dark-tx rates vs their datacarrier-inclusion policies.
• Mesh gossip of observed txids between mempool·watch browsers, so the baseline is the swarm's union view rather than one browser's.

Layout

index.html   the app: witnesses, fee histogram, datacarrier stream, dark-tx ledger
tx-scan.js   pure helpers: OP_RETURN standardness, coinbase tag → pool attribution
engine/      vendored bitcoin-kernel codec + JSON-LD consensus schemas
tests/       node test suite

Run locally

python3 -m http.server 8901    # then open http://localhost:8901/
node tests/test-tx-scan.mjs

No build step, no backend — static files on GitHub Pages.