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name: bitcoin-infrastructure-mempool-space description: | mempool.space: open-source mempool explorer + accelerator. Detailed fee tracking, mempool blocks projection, REST + WebSocket APIs. Self-hostable. USE WHEN: integrating mempool.space API, deploying self-hosted variant, evaluating fee estimation services. allowed-tools: Read, Grep, Glob

mempool.space

Open-source mempool explorer + REST/WebSocket APIs. Industry-leading mempool visibility.

Repo: github.com/mempool/mempool.

Features

• Mempool blocks projection: shows next ~10 blocks with median fees per virtual block.
• Fee estimates: /api/v1/fees/recommended returns {fastestFee, halfHourFee, hourFee, economyFee, minimumFee}.
• Address history: similar to Esplora.
• Lightning visualizer: graph view, channel info.
• Mining stats: pool distribution, block templates, hashrate.
• Accelerator: paid service to push tx into next block.

Self-host

docker compose up -d

Stack: Bitcoin Core + electrs-fork (mempool-electrs) + Node.js backend

• Nginx + frontend.

Disk ~1-2 TB, RAM ~4-8 GB recommended.

REST API

GET /api/v1/fees/recommended
GET /api/mempool
GET /api/v1/fees/mempool-blocks
GET /api/tx/<txid>/status
GET /api/block/<hash>
GET /api/address/<addr>
GET /api/v1/mining/pools/24h

Full docs: mempool.space/docs/api/rest.

WebSocket

/api/v1/ws — subscribe to live blocks, mempool, address.

const ws = new WebSocket("wss://mempool.space/api/v1/ws");
ws.send(JSON.stringify({ action: "want", data: ["blocks", "mempool-blocks"] }));

Accelerator

Paid via Lightning. Operator publishes the tx with high fee priority (via mempool.space's pool partnerships). Useful when:

• Tx is stuck due to ancestor / no RBF.
• Need confirmation in next 1-2 blocks.

Cost: usually few dollars to ~$50, depending on size + urgency.

Compared to Esplora

Aspect	mempool.space	Esplora
Mempool detail	best	basic
Fee estimation	best	OK
Lightning view	yes	partial
Mining stats	rich	basic
API spec compatibility	mempool.space-specific	spec defined

Common bugs

• Self-hosted: full sync takes days; first IBD + indexing.
• Public API rate-limited; for serious integrations, run your own or pay for premium.
• WebSocket reconnect logic essential — connections drop.

See also

• esplora/SKILL.md
• electrs/SKILL.md
• ../wallets/fee-estimation/SKILL.md
• ../libraries/mempool-js/SKILL.md