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It's Friday evening. An endpoint that normally answers in 200 milliseconds is suddenly taking eight seconds. You open Grafana. Every graph is green. CPU is calm, memory is fine, the disk isn't full. By every dashboard you have, the database is healthy. It is not healthy. This is the failure mode monitoring is worst at: the server is unmistakably alive , so nothing alerts, while inside the database something is slowly rotting. A table has bloated. An index nobody uses is dragging down every INSERT . A forgotten transaction is sitting open, holding a lock and quietly making everything worse. None of it crashes. It just degrades, a little at a time, until one Friday evening it tips over. The good news is that Postgres will tell you all of this — you just have to ask. The queries below run on bare PostgreSQL (13 or newer; one version note along the way), need no agent and no paid monitoring, and use an extension in exactly one place where it genuinely earns it. Open psql and check your own database as you read. 1. The cheapest signal: dead rows Start here, because it costs nothing and catches the most. Postgres never deletes a row in place. An UPDATE or DELETE leaves behind a dead tuple — an old version of the row — and autovacuum cleans those up later. Until it does (or if it can't keep up), the dead rows sit in the table, taking space and forcing every scan to page past them. The fastest look is pg_stat_user_tables , always available, no extension: SELECT schemaname , relname AS table , n_live_tup , n_dead_tup , round ( n_dead_tup * 100 . 0 / nullif ( n_live_tup + n_dead_tup , 0 ), 1 ) AS dead_ratio , last_autovacuum FROM pg_stat_user_tables WHERE n_dead_tup > 0 ORDER BY n_dead_tup DESC LIMIT 20 ; A dead_ratio above ~20% on a large table is worth investigating. And watch for a table where the ratio is high and last_autovacuum is empty — that means autovacuum has never successfully run on it, which is its own red flag (we'll see why in section 5; the whole story conver

The problem every self-hoster hits You built something. A local API. A Minecraft world for your friends. A self-hosted dashboard. An ERP running on the office machine. It works great — on your LAN. The moment you want someone outside to reach it, the fun begins: Port forwarding? Good luck if you're behind CGNAT, a corporate firewall, or an ISP that doesn't give you a public IP. VPN? Now every person who wants access has to install a client, join a network, and stay connected. Overkill for "let me show you this one page." Cloud deploy? Now you're maintaining two environments, paying for a VPS you didn't need, and shipping data somewhere it doesn't have to live. What most people actually want is simpler: take this one local port, give it a public address, done. That's exactly what FRP does. What FRP is FRP (Fast Reverse Proxy) is an open-source tool by fatedier that exposes a local service behind a NAT or firewall to the public internet. It's battle-tested, written in Go, and has been the go-to answer in self-hosting communities for years. The model is clean — two pieces: frps (the server) — runs on a machine with a public IP (a $5 VPS is plenty). frpc (the client) — runs on your local machine, the one with the service you want to expose. The client opens an outbound tunnel to the server. The server listens on a public port and forwards traffic back through the tunnel. NAT and firewalls don't matter because the connection is initiated from inside . [Visitor] → [frps on public VPS:7000] ⇄ tunnel ⇄ [frpc on your laptop] → [localhost:8080] That's the whole idea. It works for TCP, UDP, HTTP, HTTPS. People run Minecraft servers, remote desktops, internal dashboards, and dev previews through it every day. The catch: config files FRP works great. The friction isn't the protocol — it's the workflow . To run frpc , you write a TOML/INI config file: serverAddr = "203.0.113.10" serverPort = 7000 auth.token = "your-secret-key" [[proxies]] name = "my-web" type = "tcp" localIP = "1

Two Sum Given an array of integers nums and an integer target , return indices of the two numbers such that they add up to target . (You may assume that each input would have exactly one solution, and you may not use the same element twice. You can return the answer in any order.) Python ####Double FOR Loops (Runtime: 2100ms, Memory: 13.3MB) #DECLARE nums: ARRAY of INTEGER #DECLARE target: INTEGER class Solution : def twoSum ( self , nums , target ): Length = len ( nums ) for i in range ( Length - 1 ): for j in range (( i + 1 ), Length ): if nums [ i ] + nums [ j ] == target : return i , j return None ####Hashing Algorithm (Runtime: 0ms, Memory: 12.9MB) #DECLARE nums: ARRAY of INTEGER #DECLARE target: INTEGER class Solution : def twoSum ( self , nums , target ): Seen = {} for i , Value in enumerate ( nums ): if ( target - Value ) in Seen : return Seen [ target - Value ], i Seen [ Value ] = i return None

In a recent article, Datadog engineer Arnold Wakim shared what worked, what didn't, and the lessons they learned while evolving a critical production system using AI to overcome hard limits in its storage backend and significantly improve performance. By Sergio De Simone

Most organisations approach a Dynamics 365 Customer Engagement implementation with one question at the top of their agenda: How long will this take? It is a reasonable question, and one that deserves a precise, well-considered answer rather than a vague estimate designed to win the deal. The reality is that Dynamics 365 CE implementation timelines vary significantly, shaped by factors that are unique to each organisation: business complexity, data readiness, customisation depth, integration requirements, and internal stakeholder availability. This guide provides a structured, phase-by-phase breakdown of what a Dynamics 365 CE implementation actually involves, realistic timeline benchmarks by business size and industry, and the critical factors that either accelerate or delay your go-live date. Why there is no one-size-fits-all timeline for Dynamics 365 CE implementation Why There Is No Single Answer to the Timeline Question Dynamics 365 Customer Engagement is not a standalone application. It is a modular platform encompassing Sales, Customer Service, Field Service, and Marketing, each carrying its own configuration requirements, data dependencies, and user adoption considerations. A professional services firm deploying D365 Sales for a 25-person team operates in an entirely different context than a multi-national enterprise rolling out Customer Service and Field Service across three regions. Treating these as comparable projects, with comparable timelines, is where expectations first go wrong. As a reference framework, Dynamics 365 CE implementations broadly fall into three tiers: Implementation Scope Basic deployment, minimal customization :- 6 – 12 weeks Mid-market with integrations and moderate configuration :- 3 – 6 months Enterprise, multi-module or multi-region rollout :- 6 – 16 months These are informed benchmarks, not guarantees. What determines where your project lands within or beyond these ranges is examined in detail below. Core phases of a Microsoft Dyn

OpenAI's new family of models will continue to power Microsoft's suite of workplace and productivity apps.

Microsoft may once again be struggling to keep up with its own climate goals, according to its 2026 sustainability report. As reported by GeekWire, the report states that Microsoft's carbon emissions increased 25 percent in 2025, totalling 34 million metric tons "without select interventions." Microsoft says this was "driven primarily by the expansion of our […]

The feud between NightmareEclipse and Microsoft shows no signs of resolving soon.

canonical_url: https://quantumflow-ai-ecosystem.vercel.app/blog/26-ai-models-compared-2026-cost-guide date: 2026-07-09T10:00:00Z If you're building an AI-powered application in 2026, you have a problem: there are too many models to choose from. OpenAI has GPT-4o. Anthropic has Claude 3.5 Sonnet. Google has Gemini 1.5 Pro. Meta has Llama 3.1. And then there's DeepSeek, Mistral, Cohere, and a dozen others. Most developers solve this by defaulting to GPT-4o for everything. It's the safe choice — powerful, well-documented, and reliable. But it's also expensive: $2.50 per million input tokens, $10.00 per million output tokens. If you're processing 10 million tokens a day, that's $75+ per day, $2,250+ per month. But here's the secret: most of your requests don't need GPT-4o. In this guide, we'll compare 26 AI models across three dimensions — cost, quality, and speed — and show you how intelligent routing can cut your AI bill by up to 90% without changing a single line of your application code. The 2026 AI Model Landscape The AI model market has fragmented into three tiers. Understanding these tiers is the foundation of any cost optimization strategy. Tier 1: Sovereign Local Models (Free, Priority 100-110) These models run on your own hardware (or your users' hardware) via runtimes like Ollama. They cost $0 per token. They're sovereign — no data leaves your infrastructure. They're fast (no network round-trip). And they're getting remarkably good. Model Parameters Context Best For Cost Llama 3.1 70B (Local) 70B 128K Complex reasoning, code $0 Llama 3.1 8B (Local) 8B 128K General chat, fast responses $0 Mistral 7B (Local) 7B 32K Efficient European-language tasks $0 DeepSeek Coder (Local) 6.7B 16K Code generation & completion $0 GLM-4 9B Chat (Local) 9B 128K Bilingual (EN/ZH) chat $0 Llama 3.2 3B (Local) 3B 128K Edge devices, mobile $0 Llama 3.2 1B (Local) 1B 128K Ultra-lightweight tasks $0 CodeLlama 7B (Local) 7B 16K Legacy code tasks $0 GLM-4V 9B Vision (Local) 9B 128K Loca

When Neon became the official database partner of DEV Community, I was already a user. But the partnership made me look closer at why I chose Neon — and whether those reasons apply to other AI developers. They do. Here's why Neon is the ideal database for AI applications in 2026. The Problem: AI Apps Have Unique Database Needs AI applications have database requirements that traditional web apps don't: High write volume — every AI request generates logs, metrics, and cost data Variable load — traffic spikes when a model goes viral, then drops to zero Schema evolution — you're constantly adding models, routing rules, and analytics tables Dev/prod parity — you need to test routing changes against real production data Edge compatibility — AI APIs need sub-100ms response times globally Traditional PostgreSQL (RDS, Aurora) struggles with all five. Neon was built for them. Feature 1: Database Branching (The Game-Changer) This is Neon's killer feature. It works like git branch but for your entire database: # Create a branch from production neon branches create --parent main --name test-deepseek-v31 # Get a connection string for the branch neon connection-string test-deepseek-v31 # → postgresql://...@ep-test-deepseek...neon.tech/neondb # Run migrations on the branch npx prisma db push --url $BRANCH_URL # Test your new routing algorithm against REAL data # (the branch is a copy-on-write clone of production) # When tests pass, merge neon branches merge test-deepseek-v31 Why This Matters for AI Apps When I added DeepSeek V3.1 to my model pool, I needed to test: Would the new model break existing routing rules? Would the cost calculations be correct? Would the latency meet my SLA? With traditional PostgreSQL, testing against real data meant either: Copying production to a staging DB (hours, $$) Testing with synthetic data (unreliable) With Neon branching, I branched, tested in 30 seconds, and merged. Zero downtime, zero risk. Feature 2: Scale-to-Zero (Cost Optimization) Neon's c

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 […]

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 .

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

In Tutorial 1 Duke dashed for coffee with arcade physics. Now he sets the cup down for a calmer contest: Duke Jack , a game of blackjack. A card game has none of that arcade motion — cards sit on the felt and the rules decide who wins. This tutorial shows how the same Game Builder pattern (visual data + an onUpdate companion) handles a card game, where your code reads the cards and runs the table instead of simulating movement. We'll build a felt table, deal a real hand, and wire up the complete blackjack rules: hit, stand, the dealer's draw, and the win/lose decision. What is Codename One? Codename One is an open-source framework for building native iOS, Android, desktop, and web apps from a single Java or Kotlin codebase. Learn more at codenameone.com . If you haven't set up a project yet, the project setup in Tutorial 1 applies verbatim — only the mode changes (board mode isn't the default, so the -Dmode=board flag is required here): mvn cn1:create-game-scene -DclassName = com.example.dukejack.DukeJack -Dmode = board mvn cn1:gamebuilder Why board mode for cards? Board mode is the Game Builder's grid mode: you place elements on a flat board of cells instead of a free-scrolling world. That's a natural fit for a card table — the felt is a tile layer, and each card is an element you position by hand, carrying its own rank , suit and faceUp data. There's no physics and no camera to chase; the layout is the game state, and your rules read it. (Board mode can also tilt the grid into an isometric view through IsoProjection for tabletop games — for cards we keep it flat and top-down.) Step 1 — A card-table scene Pick New scene → Board . You get a Board (tile) layer for the table surface and a Pieces (entity) layer for the cards. Keeping the felt and the cards on separate layers matters: the felt is static grid data, while the cards are objects your rules deal, flip, and clear. A small grid (here 8×5) is all a card table needs. Step 2 — Lay the felt Select the Board layer,

Episode 1/4 — 3 incidents, one root: default GRANTs open more than you think — [CANONICAL URL EPISODE 1: fill in after push] Episode 2/4 — await mutation() lies when nobody opens the { error } envelope — [CANONICAL URL EPISODE 2: fill in after push] The morning Françoise sees zero rows, again It's a Tuesday in April 2026. I've just added the agent_readonly role to the authenticated membership — a one-liner, meant to share a GRANT for a reporting job. First SELECT on cours , Sentry receives infinite recursion detected in policy for relation "user_roles" , code 42P17 . From the office next door, Françoise is already on the phone with the Maisons-Laffitte branch: "So they can't see anything over there — is that normal?" Foreman tone, not really a question. I read the error on my screen. The difference from episode 1: this time Postgres is talking. What came out of Sentry was no longer a silent empty set — it was an explicit error. That difference saved me two days. When Postgres shouts, you listen. The trap is that what it says isn't where you're looking. I won't pretend this is obscure. A policy on user_roles that queries user_roles to decide who can read user_roles is a loop. You avoid it, you work around it with SECURITY DEFINER , you move on. The problem: my user_roles policy didn't reference user_roles . I had already cleaned it up three weeks earlier. The recursion was coming from somewhere else. The diagnostic that targets the wrong object First reflex: re-read the user_roles policy. It's clean, reads auth.email() , never calls itself. Second reflex: disable policies one by one to find the culprit. Wrong angle. -- supabase/migrations/20260420_admin_write_cours_v1.sql -- "Admin write cours" policy — original version that loops CREATE POLICY "Admin write cours" ON public . cours FOR ALL TO authenticated USING ( EXISTS ( SELECT 1 FROM public . user_roles WHERE email = auth . email () AND role IN ( 'admin' , 'super_admin' ) ) ); The recursion doesn't come from a fau

The fourth call of the week Catherine calls from the Maisons-Laffitte site on a Tuesday afternoon in early May. "It's broken, but it's a quick fix." That's her line — I know it, and she's usually right. She describes it in three sentences: the newsletter export for the enrolled-students segment comes back with ninety-two names, the planning view shows ninety-two active courses, but the counter page shows eighty-nine. Three enrolled students missing. She'd checked the database directly — they're all there. "Why three steps for that?" She's not asking for my benefit. She's asking for herself. Except this time, hanging up, I realize it's the fourth time this week I've hung up thinking the same thing. Four Supabase incidents, four fixes, four closed tickets. And not a single exception raised by the database. I reopen the three previous ones and lay all four side by side on screen. This isn't four bugs. It's one failure mode, declinated four times. The first three Episode 1 was about the default GRANT s Supabase places on functions and policies. A SQL function created without an explicit REVOKE inherits anon access that nobody wrote in the migration, and that nobody caught in review because the diff doesn't show it. The function works. It's just callable from outside. [CANONICAL URL EPISODE 1: to fill in after publication of #48 — "3 Supabase security incidents, one shared root cause: SECURITY DEFINER inherits EXECUTE TO PUBLIC"] Episode 2, an ON DELETE SET NULL cascade coupled with a CHECK NOT NULL on the target column. The parent DELETE attempts the SET NULL , the CHECK rejects it, and the transaction surfaces an error we read as a deletion failure — while it actually masks a consistency assumption we'd held for three months. The query fails loudly, which is more charitable than the other three cases, but the diagnosis heads in the wrong direction because nobody had declared that the two constraints lived in tension. [CANONICAL URL EPISODE 2: to fill in after publicati

Oddly, it wasn't the first time this had happened to the man.

"I think it's fair to say that Phase 3 did not contemplate this."

"The Starship Pez dispenser demonstrates very smart industrial design and scale."

In this article, I describe the challenges and the design of a React Native real-time mobile beat-aligned playback system for iOS and Android. The system combines personalization with low-latency, and seamless navigation and was the result of careful analysis and experimentation to address strict mobile and network constraints as well as meet user expectations. By Vladyslav Melnychenko