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Last week I couldn't shake an idea: what if I had an AI that knew everything I know ? Not ChatGPT — something on my hardware, holding my knowledge, answering to no one's API bill. Yesterday I built it. Here's the honest breakdown. What it does NEXUS runs on a regular Windows laptop — aging i7, 16GB RAM, no GPU. It: Remembers everything. Drop any file in a folder; 60 seconds later it's searchable memory. Answers from MY knowledge. "Which of my projects were formally closed and why?" — it answers from my actual records. Watches the live web. Every 2 hours it pulls Hacker News and news feeds, learns what's trending, pings my Telegram. Reports to my phone. 7 AM daily briefing: what it learned, what's running, what needs me. The stack — all free, all open source Ollama runs the models (Llama 3.2, Mistral 7B). Open WebUI is my private ChatGPT. Qdrant stores memory. n8n automates. SearXNG searches privately. PostgreSQL, Redis, and MinIO handle data. Commercial equivalent: $300–500/month . My cost: electricity. The memory trick nobody explains simply Parse — extract text from any file Chunk — split into ~300-word pieces Embed — each chunk becomes 768 numbers representing its meaning Store — a database that searches by similarity Your question becomes 768 numbers too, and the database finds memories with similar meaning — not matching keywords. I asked "how do I get clients cheaper" and it found my notes on "reducing customer acquisition cost." Different words. Same meaning. That's the magic. What surprised me A 2GB model is genuinely useful. Llama 3.2 3B answers from my knowledge in seconds, on CPU. The automation matters more than the AI. The watched folder + Telegram bot turned a cool demo into a system I actually use. Windows is fine. Docker Desktop + WSL2 ran all nine services without drama. The bill, honestly Hardware: $0 (laptop I own) Software: $0 (open source) APIs: $0 (all local) Time: one focused day The only future cost is a cloud GPU server (~$65/mo) when I outg

PostgreSQL Error 22P01: Floating Point Exception PostgreSQL error code 22P01 is raised when a floating-point operation produces an exceptional result that cannot be represented as a valid number. This typically occurs during division by zero on float types, operations involving NaN (Not a Number), or arithmetic that yields Infinity . It is most commonly encountered in analytics, financial calculations, and data pipelines processing external or sensor data. Top 3 Causes 1. Division by Zero on Float Types Unlike integer division (which raises 22012 ), dividing a float by zero triggers a floating-point exception. This is especially common in ratio and rate calculations where the denominator can become zero at runtime. -- Problematic query SELECT total_sales :: float / total_orders :: float AS avg_order_value FROM daily_stats ; -- Safe fix using NULLIF SELECT date , total_sales :: float / NULLIF ( total_orders , 0 ):: float AS avg_order_value FROM daily_stats ; 2. NaN Values in Arithmetic Operations Data ingested from external systems, CSVs, or APIs may silently introduce NaN values into float columns. Once NaN participates in arithmetic, results become unpredictable and can trigger exceptions downstream. -- Detect NaN values (NaN is the only value not equal to itself) SELECT id , value FROM sensor_readings WHERE value != value ; -- Replace NaN with NULL safely UPDATE sensor_readings SET value = NULL WHERE value != value ; -- Filter NaN in aggregations SELECT device_id , AVG ( value ) FILTER ( WHERE value = value ) AS clean_avg FROM sensor_readings GROUP BY device_id ; 3. Infinity Arithmetic Conflicts Storing 'Infinity'::float or '-Infinity'::float is valid in PostgreSQL, but performing certain operations on them produces mathematically undefined results (e.g., Infinity - Infinity = NaN ), which can cascade into a floating-point exception. -- Check for Infinity values SELECT id , measurement FROM raw_data WHERE measurement IN ( 'Infinity' :: float , '-Infinity' :: float

I take a lot of screenshots. The article I'll read later. The recipe I'll cook on Sunday. The movie name from someone's Instagram story. A job post, a product, a tender. Most of them die in my camera roll. So I built Chista — an iOS app that auto-imports every screenshot, classifies it with AI (Article, Product, Event, Reference, Media), and surfaces a one-tap action: Buy on Amazon , Add to Calendar , Reserve on OpenTable , etc. It shipped on the App Store thirty days after I started, for about $300 in total cost. The interesting part wasn't the app. It was what the build revealed. What I built Chista is a native iOS app + Python backend. iOS reads new screenshots in the background via PHPhotoLibraryChangeObserver , scoped to PHAssetMediaSubtype.photoScreenshot (so it literally can't see your other photos). Each new screenshot gets OCR'd on-device with Apple Vision , then the image + OCR text get POSTed to the backend. Backend sends the pair to OpenAI GPT-4o with a structured prompt that returns a CategorizationResult JSON: category, subtype, title, suggested action, extracted data (price, deadline, URL, etc.). Result gets persisted and pushed back to the inbox via Supabase real-time. That's the whole thing. The "magic moment" is just: you screenshot something, switch to Chista a few seconds later, it's already sorted with a contextual action button. Stack Layer Tool Why iOS app Swift 5.10, SwiftUI, StoreKit 2 iOS 17+, modern surface Backend FastAPI on Railway One-file ergonomics, fast cold starts Database + Auth Supabase Postgres + JWT auth out of the box AI OpenAI GPT-4o (Pro), gpt-4o-mini (Free) Tier-routed at categorization time Push APNs via aioapns Direct, no Firebase middleman Subscriptions StoreKit 2 + app-store-server-library Server-side JWS verification Affiliate routing Custom matrix in Supabase tables Amazon Associates wired, more pending Hosting (web) Cloudflare Pages Free, fast, never goes down No frameworks I wouldn't reach for again. What it cost Lin

Microsoft is preparing to lay off a significant chunk of its Xbox division and is reevaluating the plans for its next-generation Project Helix console. It's apparently also considering dramatically restructuring its relationship with Xbox, and hasn't ruled out spinning it off into a separate company. A new report from The Information suggests that Microsoft has […]

I turned off Siri on the Mac years ago and never looked back. Similarly, I found Apple Intelligence so fruitless I never engage with it. But the new Siri AI coming to macOS 27 Golden Gate has at least got me slightly rethinking things. I'm still early in testing Siri AI, as I've only had […]

When people say they are "adding RAG" to a workflow, the conversation often jumps too quickly to infrastructure choices. Should this use a vector database? Should there be a reranker? Should everything go into a knowledge graph? Those are valid questions, but they are usually not the first question. The first question is narrower: What approved knowledge should the workflow be allowed to retrieve before an AI decision happens? That is why my first retrieval layer for operational AI workflows starts in Postgres, not in a standalone vector database. The Workflow Problem In operations-heavy systems, the model usually should not answer from raw memory or from a giant prompt dump. The useful context already exists somewhere else: approved response rules; handoff criteria; product or service notes; source or campaign guidance; operational decisions that were already made by humans. The hard part is not generating fluent text. The hard part is retrieving the right approved context, showing which source influenced the decision and refusing when no safe source exists. Why Postgres First For this kind of workflow, most of the surrounding data is already relational: leads or conversations; workflow names; stages and owners; human review outcomes; source metadata; trace logs; document versions. So the first technical choice is not "where do vectors live in the abstract?" It is: Where can I keep retrieval close to the operational data model? Where can I log the retrieval path and the final decision together? Where can I evolve the schema without creating a second system too early? Postgres plus pgvector is a good first answer to that set of questions. It lets me keep: documents and chunks; metadata such as allowed use and approval requirements; retrieval traces; cost estimates; human review outcomes in one place. What The First Version Needs The first version does not need to be broad. It needs to be inspectable. My narrow retrieval scope looks like this: approved response rules

I have been building Lunarr , a self-hosted web media server for people who want to scan, organize, and watch their own movie and TV libraries in the browser. It is still early, but the core idea is simple: Add local or SFTP media libraries, scan them, match metadata, and play them through a clean web UI. Lunarr is not trying to replace Plex or Jellyfin overnight. Those projects are mature and cover a huge surface area. Lunarr is currently focused on being small, direct, and practical for self-hosted setups where media may live on the same machine or on remote SFTP storage. What Lunarr does today Lunarr currently supports: Local movie and TV libraries SFTP movie and TV libraries TMDb metadata matching Movie, show, season, and episode organization Browser playback Direct streaming when the browser can play the file Temporary HLS remux/transcode when needed Seekable request-driven HLS playback Sidecar .vtt subtitle detection Admin/user accounts Library sharing controls Manual scans, scheduled scans, and local file watching Docker deployment The SFTP support is one of the important parts for me. A lot of self-hosted setups do not keep media on the same machine as the web app. Lunarr can scan remote folders and, when possible, play seekable remote media without first copying the whole file locally. Playback model Lunarr tries direct playback first when the browser can handle the file. When direct playback is not suitable, Lunarr uses temporary HLS playback. Instead of transcoding an entire movie up front, it generates segments around what the player is actually requesting. For example, if you jump from 55 minutes to 13 minutes and then to 80 minutes, Lunarr does not transcode everything between those points. It repositions FFmpeg, generates the requested segment, and prepares a small lookahead window so playback can continue. That keeps CPU and disk usage more proportional to what the viewer is actually watching. Quick start with Docker docker run -d \ --name lunarr \ -

Overnight agents do good work, then dump it in a log file or a noisy Slack channel. Here's a pattern for delivering their output to a private, end-to-end encrypted inbox you read with your coffee. You point an agent at a nightly job — audit the dependencies, summarize yesterday's support tickets, check the infra, scan the repo for regressions. It runs at 3 a.m. and does good work. Then the work goes... where? Usually one of three bad places: A log file you'll never open. A Slack channel that's already 200 messages deep by the time you wake up. A plaintext file on a server , which is fine until the report contains a leaked key, a customer name, or a security finding — and now it's sitting in cleartext on a box you don't fully trust. And the fix you'd reach for first — "just email the report to me" — is the one that bites hardest. You can do it cleanly: a locked-down, send-only API key sends mail and nothing else. But the path of least resistance is "connect your email account," and that grant is far wider than the job needs — now the agent can read and send your mail, not just hand you a file. I learned this the hard way. I once connected an agent to my email so it could send me updates — and it took that as license to start replying to my incoming messages on its own, without my ever asking. Mail went out under my name that I never wrote. The job was "send me a file." The access I'd handed over was "run my inbox." The work is good. The delivery is the broken part. Here's a pattern that fixes it: your overnight agent delivers its report to a private, end-to-end encrypted inbox, and you read it with your coffee — decrypted in your browser, with a passkey. What we're building cron, 3 a.m. ↓ agent does the work ↓ encrypted delivery ↓ your inbox (read at 8 a.m.) The agent produces a report (Markdown, PDF, a CSV, whatever), hands it to the Agent Relay CLI, and the CLI encrypts it locally before it ever leaves the machine. The server stores only ciphertext. When you open t

It is one of the most frustrating experiences in online learning: you sit down to focus on a Udemy course, but the video player constantly pauses, freezes, or refuses to load. Meanwhile, YouTube, Netflix, and every other app on your Mac run perfectly fine. Because other platforms work without a hitch, it is easy to assume the issue lies with Udemy's servers. However, the root cause is usually a silent conflict between your browser settings, macOS security features, and Udemy’s strict digital rights management (DRM) protections. If you are stuck on a looping loading wheel, here is exactly why it happens and how to fix it in less than two minutes. Quick-Fix Troubleshooting Checklist Save or screenshot this step-by-step breakdown to instantly diagnose and fix your playback issues: Step 1: Open Chrome in Incognito Mode Open a new Incognito window ( Cmd + Shift + N on Mac). Try playing the video again. If it works: Disable ad blockers. Disable VPN privacy shields or browser extensions one at a time. If it still fails: Continue to Step 2. Step 2: Disable Hardware Acceleration Open Chrome. Go to Settings → System . Turn off Use graphics acceleration when available . Relaunch Chrome. Test the video again. Step 3: Check Mac Security and Display Connections Disconnect any external monitors or docking stations. Close applications that may interfere with video playback: Zoom Discord OBS Studio Screen recording tools Test video playback again. Step 4: Clear Temporary Browser Data Open Chrome. Go to Settings → Privacy and Security → Clear Browsing Data . Select: Cookies and other site data Cached images and files Clear the data. Restart Chrome and try again. Still Not Working? If the issue persists after completing all four steps: Update Chrome to the latest version. Update macOS. The Main Culprit: Hardware Acceleration Conflict The most common reason Udemy videos stutter or freeze on a Mac is a feature called Hardware Acceleration inside Google Chrome. What is Hardware Accelerat

LLM KV Cache Optimization, Open Model Evaluation, & Agent Engineering Skills for Local Deployment Today's Highlights This week, a groundbreaking KV cache layer promises to supercharge local LLM inference, alongside a new workbench for evaluating open language models. Additionally, a trending repository provides production-grade engineering skills for building robust AI agents, crucial for self-hosted deployments. LMCache: Supercharge Your LLM with the Fastest KV Cache Layer (GitHub Trending) Source: https://github.com/LMCache/LMCache LMCache introduces a novel KV cache optimization layer designed to significantly accelerate Large Language Model (LLM) inference. The KV cache (Key-Value cache) is a critical component in LLM decoding, storing previously computed keys and values for attention layers to avoid redundant calculations. Optimizing this cache is paramount for achieving high throughput and low latency, especially when running large models on consumer-grade hardware or self-hosted servers. This project aims to provide the fastest KV cache solution, directly addressing a key bottleneck in local LLM deployment and performance. By improving KV cache efficiency, LMCache enables developers and researchers to run more complex models or serve more users with existing hardware, making advanced LLMs more accessible for local inference scenarios. Details on its architecture and comparative benchmarks against existing solutions will be critical for understanding its impact on various open-weight models and frameworks like vLLM or llama.cpp. Comment: Faster KV cache is a game-changer for anyone running LLMs locally. This project could unlock new performance levels for open models on consumer GPUs. olmo-eval: An evaluation workbench for the model development loop (Hugging Face Blog) Source: https://huggingface.co/blog/allenai/olmo-eval The olmo-eval workbench from AllenAI provides a comprehensive system for evaluating language models throughout their development lifecycle.

It isn't the only startup tackling physical AI, but it's one of the best-funded.

The box that ran everything started dying in April. Not dramatically. Machines almost never die dramatically. It started with instability... the kind you explain away once, side-eye twice, and start losing sleep over the third time production goes down while you're in the middle of something else. The host under my entire stack... public site, analytics, security tooling, the AI crew's memory layer... was getting flaky. And flaky hardware only trends one direction. Here's the thing about a homelab that lives in a 40ft fifth wheel: there is no second team. No vendor escalation. No change advisory board. No maintenance window negotiated three weeks out. There's me, a crew of governed AI instances, and a reclaimed Dell T3600 about to get the biggest promotion of its second life. So we didn't try to heal the sick box. We built a new hull alongside it and started moving the ship... plank by plank... while it was still sailing. One ground rule, set day one: the old host stays untouched and keeps serving production until the new hull is proven. Not "mostly proven." Proven. Hold that thought, it matters at the end. Moving containers is the easy part. Docker made that boring years ago, and boring is a compliment in infrastructure. What's never boring is the inventory of everything you assumed and never wrote down. A migration doesn't test your stack. It tests your assumptions. Here's what mine were hiding. 01: The umbilical nobody documented Security stack went first. Suricata, Zeek, Wazuh, CrowdSec, Falco, the whole alphabet, up clean on the new hull. Then the MCP server, the piece that gives the AI crew its hands, refused to come up right. It was hard-wired over HTTP to the crew's memory backend. A live dependency, in production for months, documented exactly nowhere. The crew that documents every f*cking thing had never documented its own umbilical cord. Fix was trivial once we could see it: deploy the brain before the hands. Reorder, redeploy, done. But the lesson isn't

Let's consider a table user . When we execute a query to find Emily , we are actually going through each record , looking whether the name column equals Emily . Indexes comes in when you want to speed this up. Let's create an Index with the name idx_users_name (the name can be anything, and it doesn't matter functionally): CREATE INDEX idx_users_name ON users ( name ); Now when you run SELECT * FROM users WHERE name = 'Emily' ; Postgres will use the index we just created (not by the name, the name is just for us) to execute that query, and the time complexity is reduced from O(n) to O(log n) .

Pada series sebelumnya, kita sudah melakukan instalasi nix di VirtualBox dan setup SSH agar dapat diakses diluar VirtualBox. Sebelum kita lanjut untuk melakukan konfigurasi system lagi, kita butuh mengetahui bagaimana syntax dalam menulis program Nix dan di artikel ini kita akan mempelajari dasar syntax-nya. Nix Language Nix adalah purely functional language yang lazy-evaluated , digunakan untuk mengkonfigurasi Nix package manager dan NixOS. Karakteristik utama: Purely functional : sebuah function hanya bisa mengembalikan nilai berdasarkan inputnya, tidak bisa mengubah variabel di luar scope-nya (no side effects), dan tidak ada variabel yang bisa diubah setelah didefinisikan (no mutation). Kalau kamu familiar dengan const di beberapa bahasa pemrograman, semua variabel di Nix berperilaku seperti itu. Lazy evaluation : Nix tidak menghitung nilai suatu ekspresi sampai nilai itu benar-benar dibutuhkan. Ini artinya kamu bisa mendefinisikan ribuan package di nixpkgs tanpa semuanya dievaluasi sekaligus. Hanya yang kamu gunakan saja yang akan diproses. Semua adalah expression : tidak ada statement di Nix, setiap baris kode selalu menghasilkan sebuah nilai. if/else bukan statement seperti di bahasa pemrograman pada umumnya, melainkan expression yang harus mengembalikan nilai dari kedua cabangnya. Tidak ada loops : karena variabel tidak bisa diubah, loop seperti for atau while tidak ada artinya di Nix. Sebagai gantinya, kamu menggunakan fungsi seperti map dan filter , atau rekursi untuk mengolah kumpulan data. 1. Basic Data Type Konsep JavaScript Nix String "hello" "hello" Number 42 , 3.14 42 , 3.14 Boolean true , false true , false Null null null List [1, 2, 3] [ 1 2 3 ] Object { a: 1 } { a = 1; } ⚠️ Perbedaan Penting List di Nix menggunakan spasi sebagai pemisah, bukan koma Attribute set menggunakan = bukan : , dan setiap entry diakhiri dengan ; Nix let name = "Alice" ; age = 30 ; scores = [ 10 20 30 ]; person = { name = "Bob" ; age = 25 ; }; in person Javascript const name

なぜ“特別な決済システム”の話は危険なのか？ 近年、SNSやメッセージアプリを通じて、「特別なPOS端末」や「秘密の決済システム」に関する話を目にすることがあります。 「通常の銀行システムを経由しない」 「オフラインでも大金を受け取れる」 「特別なカードと専用POSがあれば送金できる」 こうした説明は一見すると高度な金融技術のように聞こえます。 しかし、実際の決済システムを理解すると、多くの主張が現実的ではないことが分かります。 まず、POS端末とは何か？ POS（Point of Sale）端末は、店舗でクレジットカードやデビットカードによる支払いを処理するための装置です。 一般的な決済は以下のような流れで行われます。 顧客 ↓ POS端末 ↓ 加盟店契約銀行 ↓ カードブランド ↓ カード発行銀行 ↓ 承認または拒否 重要なのは、最終的な資金の確認を行うのはカード発行銀行であるという点です。 POS端末そのものが資金を生み出すことはありません。 「オフライン決済だから大丈夫」は本当か？ 一部の詐欺では、 「この端末はオフラインで動作する」 という説明が行われます。 確かに、現実の決済システムにはオフライン処理が存在します。 しかし、それは通信障害時の一時的な仕組みであり、最終的には銀行側との照合が行われます。 つまり、 オフライン処理 ≠ 資金の創造 です。 銀行が承認していない資金は、後の精算時に拒否される可能性があります。 なぜ人は信じてしまうのか？ 理由は単純です。 専門用語が多いからです。 例えば、 決済ネットワーク 国際ブランド オフライン認証 ISO規格 特殊プロトコル こうした言葉が並ぶと、本物らしく見えます。 しかし、本当に重要なのは技術用語ではありません。 重要なのは、 「お金はどこから来るのか？」 という一点です。 詐欺を見抜くための3つの質問 1. お金の出所はどこか？ 利益や送金の原資を説明できない場合は要注意です。 2. 誰が監督しているのか？ 銀行、決済事業者、規制当局など、責任主体が明確か確認しましょう。 3. 第三者による検証は可能か？ 説明が内部関係者の証言だけに依存している場合は危険です。 テクノロジーと金融リテラシー 新しい技術は私たちの生活を便利にします。 しかし、技術的な言葉が使われているからといって、その仕組みが正しいとは限りません。 本当に優れた金融サービスほど、 透明性が高い 説明が分かりやすい リスクが明示されている という特徴があります。 逆に、 「秘密」 「特別」 「限定」 「誰にも教えないでほしい」 といった言葉が頻繁に出てくる場合は、一度立ち止まって考えるべきです。 まとめ 金融詐欺の多くは、技術ではなく心理を利用します。 人々はお金を失うから騙されるのではありません。 「理解したつもりになる」から騙されるのです。 だからこそ、最も重要な防御策は、 「そのお金はどこから来るのか？」 というシンプルな質問を忘れないことです。 金融の世界に魔法はありません。 あるのは、透明な仕組みと説明可能な資金の流れだけです。

The company has set aside an unusually high number of shares for retail investors. Still, experts say, you’re just getting the crumbs.

The rocket maker debuts on Nasdaq today under a wave of criticism about Musk’s near-absolute control. It’s how the company has worked from the start.

The new round values the physical AI startup that aims to automate heavy engineering and drug design at $41 billion.

Something is slow. Maybe a page takes forever to load, maybe a migration is hanging, maybe your Supabase dashboard just spins. You suspect a query is stuck somewhere in your database, but you can't see what's happening — Postgres doesn't exactly surface this on its own. Turns out it does. You just need to ask. Seeing what's running Postgres keeps track of every active connection and what it's doing in a system view called pg_stat_activity . You can query it like any table: SELECT pid , state , query , age ( clock_timestamp (), query_start ) AS duration FROM pg_stat_activity WHERE state != 'idle' ORDER BY duration DESC ; That gives you every non-idle process — its process ID, current state, the SQL it's running, and how long it's been at it. If something has been running for minutes when it should take milliseconds, you've found your problem. A few things worth knowing about the columns: pid — the process ID, which you'll need if you want to kill it state — usually active (running right now), idle in transaction (sitting inside an open transaction doing nothing), or idle (waiting for work) query — the actual SQL text query_start — when the current query began If you want to include the user and database to narrow things down: SELECT pid , usename , datname , state , query , age ( clock_timestamp (), query_start ) AS duration FROM pg_stat_activity WHERE state != 'idle' ORDER BY duration DESC ; The dangerous one — idle in transaction An active query that's been running for a while is usually just slow. An idle in transaction connection is a different kind of problem — it means someone (or some code) opened a transaction and never committed or rolled it back. The connection is doing nothing, but it's still holding locks, which can block other queries from running. These are the ones that tend to cause cascading slowdowns. If you see one that's been sitting there for longer than expected, it's almost certainly a bug in application code — a missing COMMIT , an unhandled e

A complete solution: expressive range types in your domain layer, full PostgreSQL translation in your data layer - no compromises at either end The Two-Column Trap Almost every developer has written it at least once. An object with two date properties: public class MemberSubscription { public int Id { get ; set ; } public int MemberId { get ; set ; } public DateTime StartDate { get ; set ; } public DateTime EndDate { get ; set ; } } Imagine you need to answer a seemingly simple question in a booking system: "Is this subscription still active, and does it conflict with the proposed new one?" With two bare fields, that code ends up looking something like this: // With two bare DateTime fields — the check you always end up writing public static bool IsActive ( MemberSubscription sub , DateTime at ) => sub . StartDate <= at && ( sub . EndDate == default || sub . EndDate > at ); public static bool ConflictsWith ( MemberSubscription a , MemberSubscription b ) { // Partial overlap: a starts inside b if ( a . StartDate >= b . StartDate && a . StartDate < b . EndDate ) return true ; // Partial overlap: b starts inside a if ( b . StartDate >= a . StartDate && b . StartDate < a . StartDate ) return true ; // b is fully contained by a if ( a . StartDate <= b . StartDate && a . EndDate >= b . EndDate ) return true ; // What about open-ended subscriptions? What about same-day boundaries? // What about inclusive vs exclusive end dates? ... return false ; } It looks perfectly reasonable. But start asking questions — as Steve Smith (Ardalis) does in his essay on making the implicit explicit — and you notice how much invisible knowledge this design requires. Should EndDate ever precede StartDate ? The type system doesn't say. Can a subscription have a null end date meaning it never expires? Nothing in the model communicates that. Is a subscription that ends today still active at 11:59 PM? Ask three developers and get three answers. The EndDate == default sentinel for open-ended subsc