Experience Base58's

Mempools: Diving In

Navigating the mempool is one of today’s modern bitcoin dev challenges. In this masterclass, we’ll dig deep into the various problems the mempool presents and techniques for over-coming them.

Mempools: Diving In

Expect to walk away with a better understanding of mempoolfullrbf, hands-on experience with both RBF and CPFP, and a good outline of the upcoming changes to mempool policies, such as package relay and v3 transactions.

Class size is limited to 20.


We’ll start with a quick version of the World Famous Bitcoin LARP, to make sure everyone has a good understanding of how the mempool and transaction gossiping works. (in-person only)

We’ll then do some lectures around various mempool fee-bumping techniques, and see if we can figure out how to execute the bumps for ourselves in the LARP and in real life on testnet (using Replit or local copies of bitcoin-core, if you have them.)

Next, we’ll move on to pinning attacks, anchors, and the current and prospective proposals for how to mitigate mempool risks while preserving miner paydays.

Topics we’ll cover

  • BIP125
  • feerate calculations
  • transaction pinning
  • CPFP
  • RBF
  • mempoolfullrbf
  • package relay
  • anchors + ephemeral anchors
  • on-chain costs and trade-offs of these approaches
  • v3 transactions + transaction sponsors

About the Instructor

Nifty’s a long time mempool contemplatoor, her thoughts on mempools are probably best known via her classic bitcoin-dev mailing list post “the mempool is dead, long live the mempool”.

What to know before class (pre-requisites)

The ideal participant for this class is someone who works as a dev on projects that either deal with layer-2s like Lightning or work on applications that are subject mempool policy constraints.