Today, we’re delighted to mark a special milestone for Brink engineer Gloria Zhao: four years of outstanding work on Bitcoin Core at Brink. From her start as the very first Brink fellow to her key role as a Bitcoin Core maintainer and member of Brink’s grant committee, Gloria has pioneered significant advancements in Bitcoin’s development—and we couldn’t be more proud.
Taking a Chance on Bitcoin (and on Brink)
Graduating from UC Berkeley in December 2020, Gloria had the pick of career paths including a coveted job offer to join Google full time after interning there the summer prior. Instead of taking the safe career path, she took a chance on Bitcoin development and, thanks to the visionary support of our founding sponsors—and early contributions from the Human Rights Foundation and Spiral— Brink took a chance on her: Gloria joined us on January 4, 2021 as the first engineer funded by Brink.
Tackling Big Problems
Gloria is most known for her work in package relay and pinning attacks, which also chronicles the majority of her time at Brink. Commenting on the motivation for this long journey, Gloria notes:
“I work in a problem-oriented fashion, so all of the other mempool policy proposals stem from the core problem of fixing pinning attacks in exogenous fee bumping, which is a crucial tool in contracting protocols. Package Relay is maybe the “flagship” proposal and certainly the biggest chunk of work, but the name is often a catch-all for anti-pinning proposals including TRUC.”
During Gloria’s first year as a Brink fellow in 2021, she was mentored by Brink co-founder John Newbery and moved to London to establish our office there. After immersing herself in the Bitcoin Core codebase and coming up with her fellowship project in early 2021, she was ready to put forth the project to the community with her Package Mempool Accept and Package RBF proposal in September of 2021.
Recognizing her momentum and expertise, Brink brought Gloria on as a grantee in 2022 to continue her work. That year she continued her research in pinning attacks and expanded the work to include fee bumping more generally, led discussions on the replace-by-fee problem space and potential improvements (documented on the mailing list), and published her first P2P protocol proposal (which later became BIP 331). That same year, she was named a Bitcoin Core maintainer by her peers, an honor that speaks volumes about her technical skill and collaborative spirit.
In 2023, Brink continued support for Gloria and her work and, recognizing the valuable technical perspectives she has on the Bitcoin Core project, also invited her to join our grant committee to help evaluate funding applications. Meanwhile, Gloria continued her work on package relay and v3 transaction relay/TRUC, projects that would eventually encompass a whopping 53 pull requests over the years. She also worked to achieve buy-in on her projects from her peers, resulting in the package relay project making the top priority projects list for the Bitcoin Core project for three consecutive releases (26.0, 27.0, 28.0).
The fruits of Gloria’s work became clear in 2024 as many of her projects were included in the recent Bitcoin Core 28.0 release, including one parent one child (1P1C) relay, BIP 431 TRUC transactions, and 1P1C package RBF. These features have garnered enthusiastic reception from Lightning engineers as well as other developers building on Bitcoin.
Maintenance and Security
But Gloria’s work goes beyond the keystone projects that she helped drive forward. She has provided thousands of review comments on the Bitcoin Core GitHub repository over the years and authored dozens of other pull requests to improve the security and reliability of the codebase including wallet and P2P work. Her role as a Bitcoin Core maintainer also involves a myriad of thankless maintenance and administrative tasks that are important for the project, including fixing bugs and creating releases.
Gloria’s thoughts in 2022 on becoming a Bitcoin Core maintainer:
“Being a maintainer means I’ll… focus on the health of Bitcoin Core and help shoulder some of the responsibilities of the other maintainers… I’m relieved to find Brink understanding and supportive, not because of the “new title,” but out of the recognition that the Bitcoin ecosystem is built on software that requires sustained, long-term effort to maintain, regardless of the coin’s price.”
Advocacy, Mentorship, and Education
Beyond code, Gloria’s impact is felt in the broader Bitcoin community through her prolific advocacy and mentorship:
- Speaking engagements: Dozens of talks at Bitcoin conferences worldwide
- Workshops: Hands-on technical sessions guiding new contributors
- PR Review Club: Facilitating in-depth code reviews for developers through this valuable resource in the Bitcoin developer pipeline
- Mentorship: Supporting several Bitcoin Core contributors
- Media appearances: Frequent guest on podcasts, explaining Bitcoin Core concepts to technical and non-technical audiences
- Bitcoin Optech contributions: Over 50 newsletter contributions (including a 10-part mempool and policy series) plus numerous podcast appearances
These activities align with Gloria’s approach to advocacy and education:
“The importance of advocacy and education is often understated. I limit this to 10-15% of my time, as there is an infinite supply of things to do. My framework is to allocate this time across a “funnel.” The top is spreading a message “the code needs work and runs on donations,” and the bottom might be recruiting somebody to work on Bitcoin Core and looking at PRs together.”
Her mentorship has had a positive impact on many developers, as Abubakar Ismail articulates:
“Gloria has been a great mentor, always willing to review PRs and answer questions. I really appreciate how she organizes and answers questions in the Bitcoin Core Review Club sessions, and later guided me on how to run some of the sessions myself. She always makes time for calls to discuss issues and answer technical questions. I’ve learned so much from her about the Mempool and other components of Bitcoin.”
Looking Ahead
From her first day as a Brink fellow to her current roles as a Bitcoin Core maintainer and serving on Brink’s grant committee, Gloria has been a valuable contributor to Bitcoin development. We’re thrilled to celebrate her four-year epoch with us and can’t wait to see where her relentless curiosity and dedication lead next.
Gloria, thank you for betting on Bitcoin, and on Brink, all those years ago. It’s been an incredible ride so far, and we look forward to everything you’ll achieve in the years to come.
About Brink
Brink is a Bitcoin research and development centre, founded in 2020 to support independent open source protocol developers and mentor new contributors. Find out more about our grants and fellowship programs, and how to support us.
Keep in touch
Subscribe to the Brink newsletter for future blog posts.