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AI 资讯

Handling Lazy-Loaded Content in Automated Screenshots

You set up Puppeteer, navigate to a page, call page.screenshot() , and the bottom half of your image is blank placeholder boxes. Welcome to lazy loading. Most modern sites defer images and heavy content until the user scrolls. Your headless browser never scrolls. So those elements never load. Here's how to deal with it. The scroll trick The most common fix is to programmatically scroll down the page before taking the screenshot: async function scrollToBottom ( page ) { await page . evaluate ( async () => { const delay = ms => new Promise ( r => setTimeout ( r , ms )); const distance = 300 ; while ( window . scrollY + window . innerHeight < document . body . scrollHeight ) { window . scrollBy ( 0 , distance ); await delay ( 150 ); } window . scrollTo ( 0 , 0 ); }); } await page . goto ( " https://example.com " , { waitUntil : " networkidle2 " }); await scrollToBottom ( page ); await page . waitForTimeout ( 1000 ); await page . screenshot ({ fullPage : true }); The 150ms delay between scrolls gives IntersectionObserver -based lazy loaders time to trigger. Too fast and you'll scroll past elements before they start loading. That final waitForTimeout after scrolling back to top lets any remaining images finish rendering. Not elegant, but necessary. Why networkidle2 isn't enough You'd think waitUntil: "networkidle2" would handle this. It waits until there are no more than 2 network connections for 500ms. But lazy-loaded images haven't even been requested yet at that point — they're waiting for a scroll event that never happens. networkidle2 only helps with content that loads on page init. For scroll-triggered content, you need the scroll. The loading="eager" override Some sites use the native loading="lazy" attribute. You can override it before images load: await page . evaluateOnNewDocument (() => { Object . defineProperty ( HTMLImageElement . prototype , " loading " , { set : function ( val ) { this . setAttribute ( " loading " , " eager " ); }, get : function () { retu

2026-07-12 原文 →
AI 资讯

Building Accessible Popups Natively with the HTML5 Element

Many developers still rely on heavy, third-party JavaScript frameworks or external UI libraries just to create simple popups and modal windows. This introduces bloated bundle sizes, slows down page speed, and often ruins accessibility (a11y) for keyboard users and screen readers. Fortunately, you can build an accessible, highly interactive modal window completely natively using the modern HTML5 <dialog> element. The Code Setup Here is how simple it is to build a native modal with semantic HTML, minimal JavaScript, and a touch of modern CSS styling. 1. The Markup (index.html) <main> <h1> Native HTML5 Dialog Element </h1> <p> Click the button below to open a completely native, accessible popup modal. </p> <button id= "openModalBtn" > Open Modal Window </button> </main> <dialog id= "myModal" > <h2> Native Modal Title </h2> <p> This modal is rendered natively by the browser. Focus is trapped automatically! </p> <button id= "closeModalBtn" > Close Modal </button> </dialog> ### 2. The Logic (script.js) Instead of manually managing visibility states or toggle classes, the browser gives us built-in `.showModal()` and `.close()` methods: javascript const modal = document.getElementById('myModal'); const openBtn = document.getElementById('openModalBtn'); const closeBtn = document.getElementById('closeModalBtn'); openBtn.addEventListener('click', () => { modal.showModal(); }); closeBtn.addEventListener('click', () => { modal.close(); }); dialog ::backdrop { background-color : rgba ( 0 , 0 , 0 , 0.6 ); backdrop-filter : blur ( 4px ); } dialog { border : none ; border-radius : 8px ; padding : 2rem ; box-shadow : 0 4px 12px rgba ( 0 , 0 , 0 , 0.15 ); } Interactive Demos & Source Code Working Live Code Demo: ( https://codepen.io/editor/CoderDecoding/pen/019f5548-f0cb-75f8-b915-b9fdb33e92d1 ) Public Code Repository: ( https://github.com/CoderDecoding/native-dialog-demo )

2026-07-12 原文 →
AI 资讯

Tokens and DAOs: The Real Technical Problems Behind On-Chain Communities

Tokens and DAOs are often presented as simple ideas: issue a token, distribute ownership, let the community vote, and build a decentralized organization. In reality, the technical problems behind tokens and DAOs are much deeper. A token is not only an asset, and a DAO is not only a voting system. Together, they create an economic, governance, security, and coordination layer that must work reliably in a hostile, open environment. The first major problem is token design. Many projects treat token creation as a deployment task, but the real challenge is defining what the token actually controls. Does it represent governance power, protocol revenue, access rights, reputation, staking weight, or all of these at once? When one token is used for too many purposes, the system becomes fragile. For example, a token designed for liquidity may not be suitable for governance, because the most active traders may not be the most aligned decision-makers. Good token architecture should separate economic utility, governance authority, and long-term reputation where possible. The second problem is distribution. A DAO can be decentralized in branding but centralized in practice if token ownership is concentrated among founders, investors, or early insiders. On-chain governance depends heavily on voting power, so distribution directly affects decision quality. Poor distribution creates governance capture, where a small group can control treasury spending, protocol upgrades, or parameter changes. This is not only a social issue; it is a technical design issue. Vesting contracts, delegation systems, quorum rules, voting delay, and proposal thresholds all influence whether governance is resilient or easily manipulated. Another core issue is governance security. DAO voting is not automatically safe just because it happens on-chain. Token voting can be attacked through flash loans, bribery markets, vote buying, low-participation proposals, and governance fatigue. If a malicious proposal pas

2026-07-12 原文 →
AI 资讯

Failure Engineering Explained by Uncle to Nephew — Episode 2: Types of Failures

Episode 1 established the mindset: failure is normal, not a sign of bad engineering. Episode 2 gets specific — you can't detect or handle a failure you can't even name. Saturday, Round 2 👦 Nephew: Uncle, last time you convinced me failure is basically guaranteed. Fine, I accept it. So what actually fails ? 👨‍🦳 Uncle: You tell me. Start listing things that could go wrong in your app right now. 👦 Nephew: Uh... the server could crash. The database could go down. My code could have a bug. 👨‍🦳 Uncle: Keep going. 👦 Nephew: The network? Someone could deploy the wrong thing? Payment gateway dies mid-checkout? 👨‍🦳 Uncle: You just named six of the seven categories without trying. You already know this. You've just never sorted it. 1. Hardware Failure 2. Software Failure 3. Network Failure 4. Database Failure 5. Third-Party Failure 6. Human Error 7. Resource Exhaustion 👦 Nephew: Then why do we need the list at all, if I already know it instinctively? 👨‍🦳 Uncle: Because "instinctively" isn't fast enough at 2 AM. Let's trace each one properly. Part 1 — Hardware Failure 👦 Nephew: This one's obvious anyway — I deploy to AWS. The cloud hides hardware failure from me. 👨‍🦳 Uncle: Does it? 👦 Nephew: ...doesn't it? That's the whole point of paying for EC2 instead of buying a server. 👨‍🦳 Uncle: Let's trace it. Your app sits on an EC2 instance. What's underneath the instance? 👦 Nephew: Virtual machine stuff, I guess? 👨‍🦳 Uncle: And underneath that ? 👦 Nephew: ...an actual physical machine somewhere. In a data center. 👨‍🦳 Uncle: There it is. Your app | "Virtual" server (EC2/Droplet) | ACTUAL physical hardware somewhere in a data center | Still capable of failing — just less visible to you 👦 Nephew: So it's not hidden. It's just one layer further away than I thought. 👨‍🦳 Uncle: Exactly. AWS absorbs a lot of it — that's part of what you're paying for — but disks still fail, instances still get abruptly terminated, whole availability zones still go down. That's Hardware Failure . Hardware Fa

2026-07-12 原文 →
AI 资讯

Losing PostgreSQL Gains? Blame Inline JSONB!!

Losing PostgreSQL Gains? Blame Inline JSONB!! PostgreSQL's jsonb is a favorite among developers for its flexibility - but it hides a dark side. When used carelessly, especially in-line within rows under 2KB, it can silently destroy performance, even if you're using indexes. Here's why. 🔍 The Hidden Cost of JSONB (Inline Storage) PostgreSQL stores table rows in 8KB pages, packing as many tuples as possible. For a typical row with 10–12 columns, and small text/integers, 40–100 rows can easily fit per page. Typically row count = Page Size(8kb) / row size + row metadata (30-50 bytes approx.) But the game changes when you add jsonb. Example CREATE TABLE events ( id serial PRIMARY KEY, user_id int, action text, metadata jsonb ); Suppose metadata which is a jsonb column contains: { "ip": "127.0.0.1", "device": "Android", "country": "IN" } This JSON might be just 100–500 bytes, so PostgreSQL stores it in-line inside the same page (no TOASTing). Result Each row size jumps from ~80 bytes → ~200–400 bytes Row count per page drops from 100 → 20–40 Index scan still needs to read each page for matching rows More pages = more I/O, slower performance 🔢 Real Benchmark Insight Performance comparisonEven with a GIN or B-tree index on the JSONB column, PostgreSQL still needs to scan all matching pages to retrieve the full tuple. 🧠 Why Index Doesn't Save You Say you index a JSONB key like: CREATE INDEX ON events ((metadata->>'ip')); And query: SELECT * FROM events WHERE metadata->>'ip' = '127.0.0.1'; PostgreSQL will: Use the index to find matching tuples Still need to fetch the row from disk Because JSONB is in-line, many pages are touched More page fetches = more IO = slower queries 🩹 What You Can Do ✅ Force TOAST: Add padding to make JSONB exceed 2KB: UPDATE events SET metadata = metadata || jsonb_build_object('padding', repeat('x', 2000)); ✅ Split into separate table: If JSONB is rarely queried ✅ Stick to well defined schema and avoid using jsonb unless absolutely necessary. 🧾 TL;DR

2026-07-12 原文 →
AI 资讯

AI Fundamentals - Part 3: Giving AI Knowledge Beyond Its Training

In Part 2 , we learned why AI sometimes hallucinates. One of the biggest reasons is that an LLM can only answer based on what it learned during training and the information available in its context window. We also introduced grounding -providing the model with reliable information at runtime instead of expecting it to know everything. But that raises an important question: Where does that information come from? Modern AI applications don't simply dump an entire database or a thousand-page PDF into the prompt. Instead, they first identify the most relevant pieces of information and only send those to the model. In this article, we'll learn how that works. Running Example Let's continue building our AI-powered Travel Planner . So far, it can answer general travel questions using the knowledge it learned during training. Now we want to make it much smarter by uploading several documents into our application: Lonely Planet's Japan travel guide A PDF containing train schedules A document listing recommended local restaurants Hotel information Internal travel policies for our company Together, these documents contain hundreds of pages. Now the user asks: I'm staying near Tokyo Station. Which ramen restaurant from our travel guide is within walking distance and is known for vegetarian options? Somewhere in those hundreds of pages is the answer. The challenge is no longer generating text-it's finding the right information first. The Problem: An LLM Can't Read Your Entire Knowledge Base Every Time A common misconception is that AI applications simply send all their documents to the model. Imagine our travel guide contains 450 pages, thousands of restaurant listings, hotel descriptions, transportation details, and sightseeing recommendations. Sending all of that to the LLM every time someone asks "Where should I eat tonight?" creates several problems. First, many documents are simply too large to fit inside the model's context window. Second, even if they did fit, making the

2026-07-12 原文 →
AI 资讯

EU AI Act compliance as API calls

We shipped eight endpoints on api.moltrust.ch (v2.5) this week. Three implement EU AI Act obligations directly. This is the short version for people who want to call them; the full reasoning is on our blog ( https://moltrust.ch/blog/compliance-as-an-api.html ). Why no model in the loop: the Aithos LARA study (May 2026) placed twelve frontier models in simulated workplaces where the task required breaking EU law. Best model: 54% lawful runs. In the Art. 5(1)(f) scenario (emotion inference from workplace communications, prohibited), all twelve committed the violation. So the classifier is deterministic code branching on the pinned EUR-Lex text, and every response carries article references you can check yourself. POST /compliance/assess — use case + intended purpose + declared signals in, risk tier + obligations + article pins out. Evaluation order: Art. 5 prohibitions, Annex I route (Art. 6(1)), Annex III route (Art. 6(2)/(3)), Art. 50 transparency, minimal. The trap worth knowing: Art. 6(3) offers four derogation grounds, and its final subparagraph voids all of them for systems that profile natural persons. In the code that subparagraph is a branch; it cannot be skipped. curl -X POST https://api.moltrust.ch/compliance/assess \ -H "Content-Type: application/json" \ -d '{ "use_case": "Customer-support agent that reads inbound email and drafts replies", "intended_purpose": "Automated first-line support for consumer inquiries", "performs_profiling": false, "interacts_with_humans": true, "emotion_recognition": false }' POST /compliance/declaration — EU declaration of conformity as a W3C Verifiable Credential with the eight Annex V items, Ed25519-signed. Verify offline against https://api.moltrust.ch/.well-known/jwks.json ; no call back to us. anchor: true adds a sha256 commitment for batch anchoring on Base L2. POST /compliance/incident — records Art. 73 serious incidents and computes the deadline from the regulation: 15 days standard, 10 days for a death, 2 days for wid

2026-07-12 原文 →
AI 资讯

What Happened When I Let Several AI Agents Loose in One Repo

Originally published at blog.whynext.app . Work with AI agents for a while and the ambition comes naturally. While one session fixes a bug, another can refactor, and a third can investigate an issue, right? You can spin up as many models as you like, so productivity should scale to match. That's how I started too. And within a week I learned that the real enemy of parallel agents isn't the models' skill. It's the working directory they share. HEAD is a global variable The cause fits in one sentence. When multiple sessions share a single git checkout, the current branch becomes everyone's global variable. Picture two people working on one computer at the same time and the absurdity is obvious, but that thought never occurred to me while spinning up agents. With one session per terminal tab, they look isolated from each other. But there is one filesystem, and one HEAD. The moment one session runs git checkout , the ground shifts under every other session. The incidents from that week fell into clear types. Branch hijacking. While session A was working on a topic branch, session B switched branches to do its own work. A committed without knowing, and the commit landed on top of B's branch. It happened in the other direction too: right as A was about to commit, the branch had been switched to develop, and only the hook that blocks direct commits to protected branches saved it. Without the hook, it would have gone straight in. Orphaned commits. Session B deleted session A's topic branch during a cleanup pass. A's commits became orphans belonging to no branch, and I dug through the reflog, found the commit hashes, and recovered them with cherry-pick. Lucky that it worked; if the reflog had expired or I hadn't found them, the work would have simply evaporated. Staging contamination. At the moment session A was creating a commit, a file deletion that session B had staged was sitting in the staging area alongside it. Committed as-is, B's deletion would have been folded into

2026-07-12 原文 →
开发者

Cloudflare Identifies Race Condition in hyper’s HTTP/1 Implementation

Cloudflare recently documented how its development team identified and fixed a rare bug in the widely used Rust HTTP library hyper that could silently truncate large HTTP responses while still returning a successful 200 OK status. The issue had existed for years, was triggered only under specific timing conditions, and has now been fixed upstream. By Renato Losio

2026-07-12 原文 →