Edge, the new nonprofit Founded by John Newbery and Mike Schmidt to train and support Bitcoin developers today announced Gloria Zhao as his first guy. After graduating from Berkeley with a degree in computer science this month, Zhao will familiarize herself with contributions to Bitcoin Core and related open-source projects under Newbery’s mentorship. Her one-year fellowship is funded by donations from Square Crypto and the Human Rights Foundation.
“I want to be a serious and long-term Bitcoin Core developer, which I can’t imagine is an extremely rare interest or anything, but there are a lot of technical and psychological barriers to overcome,” said Zhao Bitcoin Magazine. “Having a supportive community has been extremely important in my personal journey and in general, John showed a strong interest and ability to encourage new contributors to become long-term contributors. My main reason for joining the Brink fellowship instead of scholarships is the mentorship he offers. “
In particular, Zhao will focus on packet relays, a proposed upgrade to Bitcoin’s handling of unconfirmed transactions that could improve Bitcoin’s user experience, optimize the dynamics of the fee market and – perhaps more importantly – Layer 2 protocols such as the Lightning Network more robust.
A Bitcoin node’s mempool (memory pool) is the collection of transactions it has received, but which have not yet been confirmed in a block. Nodes forward transactions from their mempool to peers on the network, and miners select transactions from their mempool to include in a new block.
Mempools have a maximum size. This limit can be configured for any node (the default for Bitcoin Core nodes is 300 megabytes), but when it is full some transactions must be removed from the mempool before new transactions can be added. Currently, this selection is fee-based: transactions with the lowest fees are dropped from the mempools in favor of transactions with higher fees.
This may seem like the obvious solution, as miners normally apply the same policy when selecting which transactions to include in blocks – the ones that pay them the most fees. Yet there is a subtle – but important – difference. To maximize their income, miners not only select based on fees included in individual transactions, they also select based on the combined fees of transactions that depend on each other.
If, in technical terms, the “parent” transaction sends coins from address A to address B, and the “child” transaction sends the coins from address B to address C, the child cannot confirm or the parent does not also confirm. Thus, a miner can choose to include a parent in a block, even if it includes a very low fee, as long as the child gets a high enough fee to compensate.
It is sometimes useful for miners to base their selection on clusters of transactions rather than just individual transactions. If a low fee transaction takes a long time to confirm, the receiver may choose to spend the coins from the unconfirmed transaction on themselves in a new high cost transaction to get both confirmed. This trick is called Child Pays For Parent (CPFP).
CPFP can be especially important in scenarios where a transaction requires confirmation before a time slot expires. The most obvious example is a “court transaction” (also known as a “penalty transaction”), which is essential to the security of the Lightning Network. These transactions require timely confirmation to prevent a malicious Lightning channel partner from claiming more money than they are entitled to.
While CPFP can be used to avoid such scenarios, it doesn’t always work.
“The danger comes when, in a CPFP scenario, the child is fine, but the parent does not meet the mempool minimum policy,” explains Zhao. Say the mempool is so complete that the parent rate is lower than the transaction with the lowest rate in the mempool. Then your hands are tied. Currently, the validation logic does not take into account CPFP for such a transaction. “
In other words, if nodes drop the parent transaction from the mempool because it doesn’t have enough fees, they won’t accept the child transaction either: it issues coins that the nodes are not aware of. In the context of Lightning, this means that the court transaction would not be confirmed in time and the malicious channel partner will get away with their theft.
Packet relays would solve this problem by making a change to a node’s mempool and transaction relay policy, allowing it to apply CPFP-type logic. While implementation details have yet to be worked out, it would essentially allow for bundling dependent transactions. Bitcoin nodes accept and send transaction packets, protecting transactions that do not individually adhere to mempool policies.
“Package Relay will strengthen Bitcoin’s baseline security guarantees, allowing Bitcoin’s ecosystem to securely expand in functionality and usability through protocols such as the Lightning Network.”
Brink’s year-long fellowship program, which is unique in the Bitcoin industry, will help more developers contribute to Bitcoin projects. Fellowships will be funded through donations, with Zhao’s program funded by gifts from Square Crypto ($ 100,000) and the Human Rights Foundation’s Bitcoin Development Fund ($ 50,000).
Square Crypto is the Bitcoin development arm of Square, the payment company founded and run by Jack Dorsey (also the co-founder and CEO of Twitter). In addition to employing a small team of Bitcoin developers, the main focus of which is the Lightning Development Kit, Square Crypto has issued so far 19 grants to various Bitcoin projects and developers. Zhao’s Brink fellowship will be the 20th.
“Brink is creating the first bitcoin mentorship program of its kind, and we want to support it,” said Steve Lee, head of Square Crypto. Bitcoin Magazine. “We are delighted that Gloria was chosen as the first grant recipient, and we are pleased that our funding is going to her. The packet relay project is highly valuable to bitcoin, security critical and very much aligned with Square Crypto’s goals. “
The Human Rights Foundation (HFR) is a New York-based non-profit organization that promotes and protects human rights worldwide. Earlier this year, the foundation launched her Bitcoin development fund, a donation-based fund to support Bitcoin developers making the Bitcoin network more private, decentralized and resilient. Zhao’s fellowship is the fourth grant awarded by the Human Rights Foundation.
“HRF is delighted to support Gloria through our Bitcoin Development Fund,” said Alex Gladstein, HFR’s Chief Strategy Officer. “The focus of her work is on critical infrastructure paving the way for Bitcoin to become more private on a large scale, and is well aligned with our mission.”
He added, “This gift will be enhanced by the fact that it supports Gloria’s fellowship at Brink, where she will receive world-class mentorship and guidance, making her work as effective and efficient as possible.”