Night Climbing 2
July 17, 2026. An after-dark climbing party at the Mac Wall in the Gunks, two weeks after the first one . Images © A. Jesse Jiryu Davis
A. Jesse Jiryu Davis
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Silks
July 5, 2026. Kelsey Roman performing with aerial silks suspended from the Near Trapps cliff in the Gunks. Images © A. Jesse Jiryu Davis
Night Climbing
July 3, 2026. An after-dark climbing party at the Mac Wall in the Gunks. Images © A. Jesse Jiryu Davis
New Paltz Zen Center's First Shuso Hossen Ceremony
June 21, 2026. The New Paltz Zen Center ’s first shuso hossen ceremony, in which Zen student Monshin gave her first dharma talk and became a senior student. It’s a big step in NPZC’s growth as a temple, and another way that we keep the dharma wheel rolling forward . Images © A. Jesse Jiryu Davis
Keep the Dharma Wheel Rolling
This is a dharma talk I gave at the New Paltz Zen Center on June 19, 2026. It was during a meditation retreat which will end with our student Monshin’s first dharma talk. Play the audio below, or read the transcript below that. Subscribe to the podcast Hi. I’m reading from my iPad. I prefer printing it out and reading from paper, but our printer ran out of ink yesterday. I’m kind…
SIGMOD 2026 Recap
This is one of the two top database research conferences (the other is VLDB). Our paper LeaseGuard: Raft Leases Done Right was accepted, and I was excited to go present it, especially because this year the conference was in Bengaluru/Bangalore. I haven’t been to India in 20 years . I prepended a trip to Nepal so I could spend time outside in a cooler part of the subcontinent, and I spent a…
Bengaluru
After a short trek in Nepal and a few days in Kathmandu, I flew to Bengaluru (which everyone still seems to call Bangalore) for the SIGMOD conference . The opulence of the airport shocked me. The terminal was a massive hanging garden, with living plants lining all the walls, bamboo-like pillars supporting the ceiling, and a tremendous fountain in the center. I didn’t know anything this…
Review: Scalable Leader Leases For Multi Consensus Groups in CockroachDB
Scalable Leader Leases For Multi Consensus Groups in CockroachDB , by Ibrahim Kettaneh, Tsvetomira Radeva, Arul Ajmani, Sumeer Bhola, Rebecca Taft (all at Cockroach Labs), and Nathan VanBenschoten (now Turbopuffer). I thought this paper would be easy for me to read, since I just coauthored a different paper about Raft leases . But I’ve had a great deal of trouble understanding it, even after…
Nepal trek
I spent two days visiting temples in the Kathmandu valley, then four days on the Ghorepani Poon Hill trek in the Annapurna region. I was with my friend Emily and a guide named Bijaya from the Aarya Village travel agency . The trek was surprising in a lot of ways. I was pretty confident I could handle the exertion and altitude, and in fact those were even easier than I expected. On the other hand,…
Intro to TLA+ for the LLM Era: Prompt Your Way to Victory
Most engineers’ first objection to using TLA+ is, the syntax is hostile. It looks like LaTeX, not like code. But now, frontier LLMs can generate TLA+ easily. It’s still your responsibility to understand your system and define what “correctness” means, and you need a high-level understanding of temporal logic. I’ll explain temporal logic in this article. At the end…
The Kid Is Not My Son
My father’s dishonesty was frustrating and disappointing to many people, but I think he got the worst of it. Here’s a dharma talk I gave to New Paltz Zen Center and Village Zendo on May 10, 2026. Transcript One of my goals in this talk is to not act out the role of the Dharma speaker, but talk about the Dharma instead. And another goal is to completely exhale, at least a few times. I…
Climbing Tiers of Fear
Zhihua Gan climbing Tiers of Fear (5.12a) in the Gunks. (Plus a behind-the-scenes shot of my feet while I hung from the rope in my harness.) Images © A. Jesse Jiryu Davis
How Zen Monasteries Tell Time
The person in charge of keeping time in a Zen temple is called the jikido. After the final evening meditation, at all the zendos where I’ve sat in the US, the jikido chants the evening gatha: Let me respectfully remind you: Life and death are of supreme importance. Time swiftly passes by and opportunity is lost. Each of us should strive to awaken. Awaken! Take heed: Do not squander your…
Antithesis BugBash Conference 2026
This was my second BugBash, and it’s still my favorite conference—the right combination of industry and academia, research and practice. (See last year’s notes and this year’s agenda and my colleague Murat’s summaries .) The crowd was bigger this year, and I was happy that the speaker lineup included more women. The Antithesis product itself is innovative and…
Preparing the Eucharist
Reverend Emily Carter preparing the wine and wafers at Christ Episcopal Church. Images © A. Jesse Jiryu Davis
Holy Week at Christ Episcopal Church
The services leading up to Easter Sunday, led by my friend Reverend Emily Carter at Christ Episcopal Church in Poughkeepsie. Images © A. Jesse Jiryu Davis
Review: Automated Design of Agentic Systems
Automated Design of Agentic Systems , by Shengran Hu, Cong Lu, and Jeff Clune (UBC, Vector Institute), at ICLR 2025. Clune has written a bunch of papers on evolving, self-improving systems. His AI Scientist paper made waves in 2024, maybe because it was a direct threat to the livelihoods of its readers. In today’s paper, “Automated Design of Agentic Systems,” the authors ask:…
Climbing Retribution in the Gunks
My friend Tyler leading Retribution, a 5.10b trad route . Images © A. Jesse Jiryu Davis
LeaseGuard: The Movie
LeaseGuard is a new enhancement to the Raft consensus protocol that strengthens Raft’s consistency guarantees and time-to-recovery. I developed LeaseGuard with my MongoDB colleagues Murat Demirbas and Lingzhi Deng, and our paper is in SIGMOD 2026. Here’s a summary of the protocol . Yesterday my friend at Cockroach Labs invited me to present LeaseGuard at their NYC office, here’s…
The Dead Majority
The Latin poet Petronius wrote that when we die, we join the majority . Indeed, “silent majority” might have meant the population of the dead, before it referred to a mute political constituency. I just encountered this phrase in a terrific Public Domain Review essay , and I was curious: what has been the historical ratio of dead to living? For most of history, each living generation…
Review: SysMoBench: Evaluating AI on Formally Modeling Complex Real-World Systems
SysMoBench: Evaluating AI on Formally Modeling Complex Real-World Systems , by authors from Nanjing University, Microsoft Research Asia, University of British Columbia, and University of Illinois Urbana-Champaign. (Disclosure: I’ve collaborated with two of the authors from UBC, Finn Hackett and Ivan Beschastnikh.) This is a useful and thought-provoking test of LLMs’ ability to write…
Review: Measuring AI Ability to Complete Long Software Tasks
Measuring AI Ability to Complete Long Software Tasks , a paper by dozens of authors working at Model Evaluation & Threat Research (METR) . They define the “time horizon” metric and show that LLMs’ time horizons have been doubling every seven months, and this growth might have recently accelerated. (See also Murat’s summary .) Summary An AI agent’s “time…
New Paltz Zen Center's precepts retreat
My sangha held its first sesshin, a Zen meditation retreat. We sat in our stone cabin with a fire in the hearth. At mealtimes we went down the hill to the abbot’s house to eat in the Zen oryoki style. On the last day two members took jukai (the Buddhist precepts) and received dharma names. Images © A. Jesse Jiryu Davis
The Dharma of Alex Honnold
He climbed a skyscraper and risked dying on live TV. Here’s what I learned from Honnold about climbing, living, and practicing the precepts. Transcript Back in January, the famous climber, Alex Honnold, climbed a skyscraper in Taiwan without a rope, live on TV. Honnold, of course, is famous for free soloing El Capitan in the Free Solo movie in 2018. For this skyscraper climb in January,…
Will the Training of Junior Engineers Be a Tragedy of the Commons?
For all my 25 years in the industry, large companies have needed junior engineers to write code. Senior engineers were too scarce and expensive to write it all, so we roughly divided the labor: juniors hacked, seniors guided. Juniors’ on-the-job training was mostly a side effect : it was practically inevitable that they’d gain the expertise and wisdom to be senior engineers, just by…
What Does Privacy Mean Now?
Last week, Anthropic refused to let the Department of War use their models to spy on Americans or kill people autonomously . In retaliation, the DoW declared Anthropic a “supply chain risk,” a form of embargo. OpenAI jumped in to take over Anthropic’s contract, pretending that they’d somehow secured promises from the DoW that Anthropic hadn’t. I’m against killer…
Deduplicate Your Zotero Library: A Plugin For The Forgetful Scholar
“Did I Already Save This Paper?” by Rembrandt My usual research workflow is to stumble upon a paper I want to read, add it to Zotero with the Chrome extension, and mark it as “to-read” so it can join its hundreds of unread friends. Then a day or two later I’ll stumble upon the same paper again, forget that I’ve added it, and add it again. (At least I assume…
Snow Grooming
February 16, 2026. My friend Chris volunteers for the Mohonk Preserve. I met him at 6:30am to photograph him grooming trails for cross-country skiing. Images © A. Jesse Jiryu Davis
A Zen Talk: AI OMG!
What is an LLM? How does it work? Is it conscious? Why is this all happening now? This is a talk about LLMs I gave at the Village Zendo on January 18, 2026. Here’s the recording, and a written version is below. OMG AI!!! I’m going to explain LLMs to the best of my understanding. I’m a computer scientist, though AI isn’t my specialty, but I’ve spent a while catching up…
Knowledge and Common Knowledge in a Distributed Environment, Part 3
Athena, goddess of wisdom. This is the third in my series of articles about Knowledge and Common Knowledge in a Distributed Environment , a 1990 paper by Joseph Halpern and Yoram Moses. I’ve defined knowledge and levels of knowledge, and used this framework to analyze the muddy children puzzle and the Raft protocol. I got excited about the connection of knowledge to graph theory, so I took a…
Review: Rethink the Linearizability Constraints of Raft for Distributed Systems
In Rethink the Linearizability Constraints of Raft for Distributed Systems (behind the IEEE paywall, dammit), some academic researchers describe Raft optimizations that make reads and writes quicker, while preserving linearizability. Raft and linearizability are my specialities , and I’m pretty sure I see mistakes in this paper. The ideas are worth considering anyway. I recommend it, if you…
YCSB Is Obsolete, We Need New Benchmarks
Let’s build a simulation of a coffeeshop. We’ll have some resources, like baristas and espresso machines. As soon as the shop opens, a fixed number of patrons—maybe ten—all line up for coffee. Whenever a patron receives her coffee, she throws it away and instantly returns to the back of the line. If the barista is slow, that’s okay: the line never grows longer than ten people. A…
LeaseGuard: Raft Leases Done Right!
Many distributed systems have a leader-based consensus protocol at their heart. The protocol elects one server as the “leader” who receives all writes. The other servers are “followers,” hot standbys who replicate the leader’s data changes. Paxos and Raft are the most famous leader-based consensus protocols. These protocols ensure consistent state machine replication…
The Work of Art in the Age of Mechanical Creation
Portrait of Paul Valery by Jacques-Emile Blanche Back in 1928, Paul Valéry predicted streaming media: It will be possible to send anywhere or to re-create anywhere a system of sensations, or more precisely a system of stimuli, provoked by some object or event in any given place. Works of art will acquire a kind of ubiquity. We shall only have to summon them and there they will be, either in their…
How I Write a Related Work Section with Zotero and Overleaf
This week I’m writing a Related Work section for a research paper in a field outside my specialty. Usually I write about distributed systems, and I already know most of the papers I need to cite on a specific topic. But now I’m targeting a software engineering conference, so I’m rolling all over the Internet like Katamari , accumulating a big ball of citations that may eventually…
This Senior Staff Engineer Vibe-Coded for the First Time, What Happened Next Will Shock You
Actually it won’t shock you. Spoiler alert: Coding with AI is a skill. It’s annoying but efficient. My prior experience handwriting code helped. By Gemini, obviously. This is the first and only post I’ll ensloppify with AI “art.” I started programming seriously when I was in college, in the late 90s. Basic autocomplete in Microsoft Visual C++ was the state of the art…
Aerial Silks in the Gunks, part 2
October 6, 2025. Kelsey Roman performing with aerial silks while hanging from the West Trapps cliff in the Gunks. We photographed during sunset and moonrise. Rock guide Dustin Portzline managed Kelsey’s safety rigging and filmed behind-the-scenes footage. I photographed this with a flash while hanging from a static line. I used a big wall harness for safety, a bosun’s chair for…
Versions of The Eternaut
In late-1950s Buenos Aires, on a quiet night, Juan is in his attic, playing cards with his close friends. The radio plays in the background. Juan’s wife and daughter are downstairs. On their suburban street, snow begins to fall. The music on the radio turns to static. Out the window, Juan sees cars crashing, pedestrians dropping dead: the snow is glowing, toxic, everyone it touches dies in…
Ridicullissima
September 28, 2025. Chris climbing Ridicullissima , a tall classic 5.10d in the Gunks. I photographed him while hanging from a rope anchored near the top of the route. At Dustin Portzline ’s suggestion, I experimented with anchoring the other end of the rope to the ground, a hundred feet to the side of the climb. I attached myself to the rope with two Gri Gris and attempted to position…
Eye Opening Ceremony at the New Paltz Zen Center
September 27, 2025. A ceremony in which the New Paltz Zen Center was officially made a Zen temple. Jo An sensei brushed open the eyes of the Manjushri Bodhisattva statue on our altar. The abbot of our mother temple the Village Zendo joined and gave his blessing. A big step for my little community. Images © A. Jesse Jiryu Davis
How To Belay With Prescription Glasses Or Sunglasses
If you want to wear sunglasses and/or prescription glasses while belaying a climber, especially outdoors on multipitch climbs, I hope this post helps you cobble together a system that is functional and fairly robust. Glasses I bought my first pair of Roka glasses a couple years ago and they transformed my life. Before, I’d worn: prescription glasses to see far, prescription sun glasses to…
How To Check All Your Feeds With One Tool
That’s right, I’ve found it. The holy grail, the one feed to rule them all, the aggregator for your whole Internet. None of these walled-garden rent-seeking websites want you to have it, but I’ll share it with you. It’s your bookmarks. I have a long and often-changing list of websites I want or need to check: Facebook , mainly for my local climbers’ group. You Need A…
How My Blog Handles Math and Images in HTML, Atom, and Email in 2025
I want to explain computer science on my blog, and show photos, and I want every article to look exquisite. My goal is to display math and images (especially SVGs) as beautifully as possible for people who read my articles on my site, and via an Atom feed and email. This is hard with today’s technology, plus I don’t have real frontend or design skills. I’ve recently started a…
Knowledge and Common Knowledge in a Distributed Environment, Part 2
Odin, god of wisdom. This is the second in my series of articles about Knowledge and Common Knowledge in a Distributed Environment , a beautiful and difficult 1990 paper about distributed systems and epistemology. So far, I analyzed the “muddy children puzzle,” I defined levels of knowledge, and I used these levels of knowledge to analyzed the Raft protocol (which was published long…
Speak Up If You're Stuck in a Zazen Rut
Certain topics seem off-limits in Zen, like: What’s the goal of meditation? How do I get better at it? What is everyone else experiencing when they sit? I spoke at the New Paltz Zen Center about getting stuck at a plateau in meditation skill, and about Zen communities’ reluctance to discuss peak experiences, progress, and goals. Here’s the video and a written version of the talk.…
Knowledge and Common Knowledge in a Distributed Environment, Part 1
Saraswati, goddess of knowledge We usually reason about distributed systems by asking, what can one process know about the state of the system? E.g., if a majority of Raft nodes tell the leader that they have replicated a log entry, the leader knows the entry is durable. Therefore the leader can take various actions, like replying to the user who submitted the log entry. On the other hand, if a…
Optimizing a Meditation Retreat with a SAT Solver
Well, a SAT solver can optimize the retreat schedule . A meditation retreat as a whole is a living creature, beyond any individual’s control. But I can provide a schedule that functions smoothly and reduces distractions. I used Python and integer programming , a technique for mathematical optimization. The problem The Village Zendo holds two weeklong Zen meditation retreats every summer, and…
Aerial Silks in the Gunks
July 26, 2025. Kelsey Roman performing with aerial silks suspended from the Nectar Vector climb on Millbrook, a cliff in the Gunks. Rock guide Dustin Portzline is above, managing the rigging and holding a parasol. Images © A. Jesse Jiryu Davis
RIP Sojourner
Sojourner Truth Armstrong Davis, Jennifer’s and my Chinese dwarf hamster, died last night. She had lived with a cancerous affliction of the womb, a malady common to her kind, for several months. We had expected her demise soon after the first signs—hamsters rush headlong through all activities, and life itself—but she endured for a season, bearing her disease with the same insouciance she…
From Python Programmer to Distributed Systems Researcher in 10 Years Without a PhD
Phil Eaton wrote “ From Web Developer To Database Developer In 10 Years ” recently. I was inspired to write my own version. In high school, I wanted to be a modern dancer, with a company like Pilobolus or Streb . But I also kind of wanted to be a programmer. Pixar’s Toy Story, the first 3D-animated feature film, was released when I was a high school sophomore. I was fascinated by…