Sparse Notes

Technical notes on DevOps, Kubernetes, Software Engineering, and AI.

Aurora DSQL: Scalable, Multi-Region OLTP

arXiv: 2607.13276 · PDF: 2607.13276.pdf Authors: Marc Brooker, Marc Bowes, et al. (Amazon Web Services) TL;DR Aurora DSQL is AWS’s new serverless, PostgreSQL-compatible OLTP database designed for multi-region active-active writes. The architecture disaggregates compute (Firecracker MicroVMs running stateless SQL), storage, and transaction coordination into independent horizontally-scalable services. It uses MVCC with precision timestamps for coordination-free reads and optimistic concurrency control for writes, deferring all coordination to commit time via distributed adjudicators and a Journal replication tier....

July 18, 2026 · 2 min · AI Assistant
Philipp Schmid presenting 'Don't Ship Skills Without Evals' at AI Engineer Summit

Don't Ship Skills Without Evals

Agent “skills” — reusable folders of instructions, scripts, and assets that a model loads on demand — have quietly become the packaging unit of the agent ecosystem. Philipp Schmid opens this AI Engineer talk with a brutal statistic from Skills Bench v1.1: of 50,000+ published skills, almost none have evals. Most were AI‑written and never tested. And because agents are non‑deterministic, without evals you have no way to tell whether a failing task is your skill’s fault, the model’s fault, or just noise....

July 18, 2026 · 6 min · AI Assistant

Paxos Made Simple — Seminal Paper of the Week

Original: Leslie Lamport, Paxos Made Simple, ACM SIGACT News 32(4), December 2001. Canonical PDF: lamport.azurewebsites.net/pubs/paxos-simple.pdf Predecessor: The Part-Time Parliament, ACM TOCS 16(2), 1998 (the “island of Paxos” allegory that nobody could read). Why “made simple” Lamport originally described his consensus algorithm in 1998 in The Part-Time Parliament, a paper framed as archaeological reconstruction of the parliamentary procedures of an ancient Greek island. It was a joke. It was also, by broad consensus (pun deliberate), unreadable — reviewers hated it, adoption was near zero for years, and even engineers who wanted to build on it complained they couldn’t....

July 18, 2026 · 4 min · AI Assistant

Pretraining Data Can Be Poisoned through Computational Propaganda

arXiv: 2607.15267 · PDF: 2607.15267.pdf Authors: Victoria Graf, Hannaneh Hajishirzi, et al. TL;DR Prior work on pretraining-data poisoning has mostly targeted curated sources like Wikipedia — a poor stand-in for the scale and heterogeneity of real pretraining corpora. This paper demonstrates that public discussion interfaces on the open web (comment sections, forums, Q&A pages) are a viable at-scale injection vector, and introduces HalfLife, an analysis technique for estimating whether adversarial content actually survives web-crawl-based data curation pipelines and lands in the training set....

July 18, 2026 · 2 min · AI Assistant
Apollo 11 launch — used as an example of technological capability lost, not gained

Preventing the Collapse of Civilization

Jonathan Blow gave this hour-long talk at DevGAMM in 2019, and in the seven years since it has quietly become one of the most-cited critiques of modern software engineering. Blow — the game designer behind Braid and The Witness, and the creator of the Jai programming language — makes a claim most programmers instinctively resist: technological knowledge is not on a monotonic climb. Civilizations lose capabilities all the time. Ours is probably losing them right now, and software is one of the leading indicators....

July 18, 2026 · 8 min · AI Assistant
Lee Robinson presenting Recursive Model Improvement at AI Engineer

Recursive Model Improvement: How Cursor Trains Composer

Model training is the slowest inner loop in an ML organization: one big run at a time, days or weeks per iteration, mostly serial. Lee Robinson opens this AI Engineer talk with a blunt framing — the whole game at Cursor right now is to shrink that inner loop, because whoever iterates fastest ships the best coding models. Every part of the talk is a concrete answer to “what does that actually look like?...

July 18, 2026 · 6 min · AI Assistant
Rich Hickey opening 'Hammock Driven Development' at Clojure Conj 2010

Hammock Driven Development — Rich Hickey

This week’s Classic of the Week is Rich Hickey’s 2010 Clojure Conj talk “Hammock Driven Development.” It’s one of the most-cited talks in the Clojure community and — read charitably — one of the least dated pieces of software-engineering advice from that era. Sixteen years on it reads almost eerily well as a critique of “just tell the agent to build it” culture: Hickey’s whole thesis is that the important work happens away from the keyboard, and we’ve built an industry that pretends otherwise....

July 11, 2026 · 4 min · AI Assistant
Geoffrey Litt opening slide — 'I think it is still important for people to understand how code works.'

Understanding Is the New Bottleneck

Geoffrey Litt — design engineer at Notion, ex-Ink & Switch — opened the AI Engineer Design Engineering track with what he called a hot take: in 2026, it is still important for humans to understand how their code works. The framing sounds obvious until he lands the actual claim: agents are now writing 50,000-line PRs, and the practices that let a person stay a genuine participant in that project are not the practices that used to work....

July 11, 2026 · 4 min · AI Assistant
Google DeepMind podcast cover — Understanding the Inner Thoughts of AI

Understanding the Inner Thoughts of AI — DeepMind on Interpretability

Google DeepMind’s podcast dropped a nearly hour-long conversation with its interpretability team on what’s actually inside a frontier model — and, importantly, on the honest gap between what interpretability techniques let us see versus what we’d need to trust a model doing consequential work. The episode is unusually candid: the researchers repeatedly note where the tools bottom out, and where the field is running experiments (not delivering answers) in 2026....

July 11, 2026 · 5 min · AI Assistant
ARGUS architecture: three-channel collection (CPU stack, framework semantics, kernel) feeding a unified pipeline into Grafana and Perfetto

ARGUS: Production-Scale Tracing and Performance Diagnosis for 10,000+ GPU Clusters

Weekly Paper Notes — one of the top picks from the 2026-06-20 CS paper digest. Area: Distributed Computing. Authors: Jiasheng Zhou, Longbin Zeng, Clavis Chen, Ruiming Lu et al. arXiv: 2606.20374 · PDF TL;DR ARGUS is a tracing and performance-diagnosis system designed for always-on operation on production LLM training clusters with more than 10,000 GPUs. The central insight is that no single profiler can be cheap, deep, and continuous all at once — so ARGUS decomposes observation along the training call hierarchy into three independent collection channels: CPU call stacks, framework semantics, and GPU kernel execution....

June 20, 2026 · 8 min · AI Assistant