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How should group chats work in decentralized systems?
Nvidia is a victim of the compute marketplace it created
Having proven how valuable compute can be, the company finds itself at the center of a market everyone wants to be in — while simpler technologies and less interesting companies get rich on the sidelines.
Postgres locks do not scale
GPT-5.6
https://deploymentsafety.openai.com/gpt-5-6/gpt-5-6.pdf https://developers.openai.com/api/docs/guides/latest-model
ChatGPT Work
Microsoft’s patch Tuesdays are about to get bigger
Windows 11 updates could soon include fixes for more security issues at once. Microsoft said in a blog post on Thursday that it's now using AI to "identify potential issues earlier," which means "customers will see a higher volume of security updates included in each security release." Hackers, even amateurs, have increasingly been using AI […]
NEO's Hands – An API to the Physical World
Show HN: Devthropology – Better Insights for GitHub Repos
Devthropology is a passion project built on top of GitHub pull data. The name is a play on developer anthropology. Pull request data can be cut a lot of ways. The functionality has been built out of curiosity as I want to see different insights into codebases that I work on. Some of the data is typical and other parts I haven't seen elsewhere. I think of this as an improved GitHub Insights page, with faster performance, more detail, and a focus on how work moves through a codebase. The main enti
The Next Chapter for ChatGPT
How GitHub gave every repository a durable owner
GitHub had over 14,000 repositories. Fewer than half had clear ownership. Here's how we gave every active repository a validated owner in under 45 days, archived the rest, and made ownership the foundation for everything that followed. The post How GitHub gave every repository a durable owner appeared first on The GitHub Blog .
AI 2040: Plan A
Degeneracy Is a Symptom
The 1X Neo Robot Has Freaky Fast Fingers
The soft, oddly intimate home-chore robot has been given some very tactile hands.
Auditory and spontaneous movement responses to music over first postnatal year
How Vector Search Actually Works: IVF and HNSW
Every system that does "semantic" anything — RAG pipelines, recommendation engines, image search, dedup — boils down to one operation: given this vector, find the closest ones out of millions. The vectors are embeddings, a few hundred to a couple thousand numbers each, and "closest" means closest in meaning. You'd assume the database either scans all of them (slow but correct) or uses some clever tree to jump straight to the answer. It does neither. Instead it deliberately settles for the approximately closest vectors — and that compromise is the entire reason vector search is fast enough to exist. Two algorithms do almost all the heavy lifting in practice, in pgvector, Qdrant, FAISS, and the rest: IVF and HNSW . Here's what they're actually doing under the hood, and how to choose between them. Why "exact" is off the table The natural objection is: why approximate? Just find the real nearest neighbor. In two or three dimensions you could — a k-d tree or similar structure prunes away big regions of space and finds the true closest point quickly. The trouble is that embeddings live in hundreds of dimensions, and high-dimensional space is deeply weird. It's called the curse of dimensionality . As dimensions grow, the distance to your nearest point and the distance to your farthest point drift toward being almost the same. Formally, the contrast (d_max − d_min) / d_min shrinks toward zero. When everything is roughly equidistant from everything else, a tree can't confidently say "skip this whole branch, it's too far" — the bounding regions all overlap, every branch looks plausible, and the search degrades into checking nearly everything. Exact indexes quietly collapse back into brute force. So we change the question. Instead of "prove you found the nearest," we ask "quickly find something very probably among the nearest." That's approximate nearest neighbor (ANN) search, and it swaps a guarantee for speed. The quality knob becomes recall : of the true top-k neighbors, wh
“PostgreSQL resolves uniqueness through heap tuple visibility”
I recently commented on Jonathan Lewis’s blog, Savepoint Funny , where I compared how PostgreSQL handles uniqueness differently: “PostgreSQL resolves uniqueness through heap tuple visibility". This deserves a more detailed explanation. In Oracle, unique indexes store unique entries because the B-tree key is the index key, preventing duplicates. Non-unique indexes add the ROWID to ensure that all entries are physically unique, even when indexed column values are duplicated. In PostgreSQL, all indexes, even unique ones, created explicitly by CREATE UNIQUE INDEX or implicitly to enforce a unique constraint, behave like non-unique indexes by appending the TID (tuple ID, similar to Oracle's ROWID) to the index key. This indicates that the index itself doesn't guarantee physical uniqueness, allowing multiple entries to have identical logical keys but point to different heap tuples. The actual uniqueness verification occurs at the heap level, not within the index entries. Initially, this might seem unusual—a unique index that permits duplicates. However, PostgreSQL requires this because of its MVCC system. MVCC allows duplicate entries to coexist in an index, since they can represent different versions of the same logical row. Still, PostgreSQL must guarantee that no MVCC snapshot views two rows with the same index key. Oracle doesn't face this issue because its MVCC implementation also versions index blocks, allowing a single index version to maintain unique keys. Let’s show that. Page inspect In PostgreSQL, the heap contains the table data, and index entries point to heap tuples. Visibility depends on the heap header, especially the transaction information. Index scans often visit the heap pages to check visibility, except for index-only scans, which use the heap's visibility maps as an optimization. B-tree indexes can store entries for multiple versions of the same logical row, including versions that are no longer visible to current snapshots. To ensure uniqueness, the
Farage left fighting a trash can as the UK populist's election gamble backfires
Architecture Decisions Behind Building a Simple Personal Software Tool
How I moved from a traditional web application mindset to exploring local-first architecture I wanted to build a simple software tool for my personal use. Nothing complicated. Something in the category of tools people build for themselves: A personal expense tracker A budgeting application A private knowledge management tool A personal organization system The important characteristic was this: The data belonged to one person. It was not a social application. It was not a collaboration platform. It did not need users interacting with each other. There was no requirement for: Public profiles Sharing updates Real-time collaboration Social features It was simply a tool that helped one person manage their own information. When I started thinking about building it, my first instinct was the most natural one for me. I am a web application developer. My comfort zone is building web applications. So my first thought was: "Why not build a Ruby on Rails application?" Something like: User | Web Application | Ruby on Rails API | PostgreSQL Database This is an architecture I have worked with many times. The workflow is familiar: Create models Build controllers Add authentication Store data in a database Deploy the application Access it from anywhere This is a proven architecture. For many products, this is exactly the right approach. But while thinking about this project, I asked myself a different question: Am I choosing this architecture because the problem requires it, or because it is the architecture I already know? That question changed the direction completely. Understanding The Actual Problem Before choosing technology, I wanted to understand the nature of the problem. What kind of application was I actually building? There is a big difference between building: A social network A marketplace A collaboration platform A communication application versus building: A personal tool A private utility A single-user productivity application In the first category, the server is the
The project file is the interface: letting AI agents drive a video editor
Last week I open sourced FableCut , a Premiere-style video editor that runs in the browser and that AI agents can operate. It hit the front page of Hacker News ( thread ), and the questions there made me realize the interesting part isn't the editor. It's one design decision: the project file is the interface. The usual way, and why I flipped it Most AI video tools hide the edit behind an API. You call addClip() , applyFilter() , and the tool owns the state. If you want a human to touch the result, you build a whole collaboration layer. FableCut does the opposite. The entire timeline lives in one JSON document, project.json : media, clips, tracks, keyframes, transitions, markers. The editor UI reads it. The export renders it. And anything that can write JSON can edit video: Claude Code through MCP, a Python script, jq , or you with a text editor. { "id" : "c_title" , "kind" : "text" , "track" : "V3" , "start" : 0 , "duration" : 2.2 , "props" : { "text" : "HANDMADE" , "font" : "Bebas Neue" , "glow" : 45 , "textAnim" : "letter-pop" } } That clip is a glowing kinetic caption. There is no API call that creates it. Writing it into the file IS creating it. SSE as a doorbell, not a data channel The first question on HN was "what's the benefit of SSE here?" Fair question, because the SSE channel does almost nothing, and that's the point. The server watches the project file with fs.watch , debounces 150ms, and pushes the literal string change to the browser. No payload. The browser re-fetches the project and re-renders. The whole mechanism is about 15 lines on a bare node:http server. Why not WebSockets? Because the data only flows one way. Everything that writes (the UI, an agent, a shell script) goes through REST or the filesystem. The browser only ever needs to hear "something changed, go look." An event with no payload can't arrive out of order, and a missed event costs nothing because the next fetch has the latest state anyway. The revision counter, or: how a human and