Mempool Accelerator
for Electrum

Un-stick any Bitcoin transaction, from inside your wallet

github.com/svanstaa/electrum-accelerate-plugin

The problem: a stuck transaction

  • You (or someone paying you) chose 1 sat/vB. Then fees spiked to 15 sat/vB.
  • Miners pick the best-paying transactions; yours waits behind every projected block.
  • It can sit for days, or be purged from mempools altogether.
  • Meanwhile the coins are in limbo: the payment hasn't arrived, the change can't be spent, and a Lightning channel can't open.

"Why hasn't my payment arrived?" is one of the most common Bitcoin support questions.

Mempool Accelerator plugin for Electrum

Who can fix it, and how?

Situation RBF
(replace with a higher fee)		 CPFP
(child pays for parent)		 Accelerator
I sent it, BIP125 signaled yes if I have change yes
I sent it, no RBF signal no if I have change yes
Someone is paying me not my inputs if the output is big enough yes
Lightning channel funding would break the channel change only yes
Tiny output / no change / too many ancestors no no yes
Not my transaction at all no no yes
Hardware wallet, multisig, watch-only needs signing needs signing no signing
Mempool Accelerator plugin for Electrum

Why that's hard for users

  • Three tools, each with hidden preconditions: RBF signals, dust limits, ancestor limits, who holds the keys.
  • Each tool is priced differently: a replacement fee, a child that pays for the whole package, or a service fee.
  • What target fee rate is actually "enough"? That depends on the live mempool, not on a guess.
  • Electrum offers RBF and CPFP but doesn't say which one to use, what it costs, or that a third option exists.
Mempool Accelerator plugin for Electrum

How the mempool.space Accelerator works

  1. Ask for a quote for a txid (no new transaction).
  2. Pay the invoice out of band (over Lightning, in this plugin).
  3. mempool.space has participating mining pools prioritize the transaction as if it paid the higher rate.
  4. Track it: requested → accelerating → mined.

Cost = bid to miners + service base fee (+ size fee)

Effective rate = (fee + bid) / vsize

On mainnet today: about 75,000 sat base fee + ~2,000 sat bid.
Participating pools mine ~70–80 % of blocks.

Mainnet only. The accelerator has no testnet API.

Mempool Accelerator plugin for Electrum

The solution: an advisor in the transaction dialog

An Accelerate button on every unconfirmed transaction:

  • Detects your role and the transaction's state.
  • Prices RBF, CPFP and the Accelerator side by side, and says why an option is impossible.
  • Recommends the cheapest option that reaches your target.
  • Executes any of them: Electrum's own fee-bump dialogs, or quote, Lightning payment and live tracking.

Mempool Accelerator plugin for Electrum

The accelerometer

  • Needle: your transaction's current fee rate.
  • Coloured zones: the live mempool's projected blocks, from red (stuck) to green (next block).
  • Cyan handle: drag (or scroll) to set your target. Every option is re-priced instantly.
  • Markers show where RBF, CPFP and ACC would land.
  • After paying, the needle swings to the accelerated rate.
Mempool Accelerator plugin for Electrum

Demo: from stuck to mined


1. Stuck
1.5 sat/vB, only the accelerator can help

2. Paying
invoice checked against the quote, paid over Lightning

3. Accelerating
the needle swings to the accelerated rate

4. Mined
tracked until it's in a block

Demo mode runs on testnet4 against a local fake mempool.space: a congested mempool, real testnet4 transactions and a simulated payment.
No real funds move. One command: scripts/demo.sh

Mempool Accelerator plugin for Electrum

Under the hood

  • analyzer.py: pure decision logic for every scenario, unit-tested
  • api.py: mempool.space explorer and accelerator client
  • wallet_facts.py: reads role, change, ancestors and keystore type from Electrum
  • gauge.py: the QPainter accelerometer widget
  • qt.py: dialog, hooks and payment flow
  • Privacy: requests go through Electrum's proxy. With Tor, the plugin uses mempool.space's onion address.
  • Safety: refuses an invoice more than 2 % above the quote; remembers payments, so you can't pay twice.
  • Distribution: a reproducible zip, authorized with Electrum 4.8's plugin-signing scheme.
Mempool Accelerator plugin for Electrum

Status and next steps

Works today: Electrum 4.8 on Linux (AppImage), mainnet, paid over Lightning, plus a full demo mode that moves no real funds.

Next steps

  • Android (Electrum's QML UI doesn't load external plugins yet)
  • Pay on-chain or by card, through the accelerator's other payment options
  • Batch-accelerate several stuck transactions
  • Advise on full-RBF replacements of non-signaling transactions

Try it

git clone https://github.com/svanstaa/electrum-accelerate-plugin
cd electrum-accelerate-plugin && scripts/demo.sh
Mempool Accelerator plugin for Electrum