AI 资讯
Mobile app performance that lasts
Users judge a mobile app in the first few seconds, and they judge it harshly. A slow launch, stuttering scroll, or a device that runs hot will sink an otherwise good app faster than a missing feature. Performance isn't one metric — it's four distinct areas, each with its own causes and fixes. Here's how to keep all of them healthy. Startup time — the first impression Time from tap to usable screen is the metric users feel most. Every extra second measurably increases abandonment. The usual culprits are doing too much before the first frame: heavy synchronous work at launch, loading data you don't yet need, and oversized bundles. Fixes: Defer non-essential initialization until after the first screen renders Lazy-load features and screens instead of loading everything upfront Show a real first screen fast, then hydrate data — don't block on the network Trim your dependency footprint; every library adds to startup cost Rendering — kill the jank Smooth means hitting the device's frame budget (about 16ms per frame for 60fps). Dropped frames show up as stutter during scrolling and animation. The main causes are doing heavy work on the UI thread and rendering more than you need. Virtualize long lists so only visible rows render (FlatList, RecyclerView equivalents) Move expensive work off the main thread Avoid unnecessary re-renders — in React Native, memoize and keep render functions cheap Optimize images: right-sized, cached, and in efficient formats Memory — don't get killed The OS terminates apps that use too much memory, and users read that crash as your bug. Leaks and oversized assets are the main offenders. Watch for retained references, unbounded caches, and full-resolution images held in memory. Load and decode images at display size, release resources when screens unmount, and cap in-memory caches. Battery and network — the invisible costs Users blame the app that drains their battery even if they can't name why. The big drains are aggressive polling, chatty netwo
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Crushing 5GB of XML: Building a Blazing Fast Apple Health Parser with Rust and ClickHouse
We’ve all been there. You click "Export Health Data" on your iPhone, wait ten minutes, and receive a massive, bloated export.xml file. If you've tracked your fitness for years, this file can easily exceed 5GB. Try opening that in Python’s ElementTree or even pandas , and your RAM will cry for mercy. This is a classic Data Engineering challenge: transforming high-volume, semi-structured XML into actionable insights without waiting an eternity. In this tutorial, we are going to build a high-performance parser using Rust performance techniques, Rayon for parallelism, and ClickHouse for lightning-fast OLAP queries. By leveraging Rust's zero-cost abstractions, we'll turn a 20-minute Python slog into a sub-30-second sprint. 🚀 The High-Level Architecture Handling 5GB of XML requires a streaming approach. We cannot load the whole file into memory. We will stream the XML, parse segments in parallel, and ship them to ClickHouse using Protocol Buffers for maximum serialization efficiency. graph TD A[Apple Health export.xml] --> B[Streaming XML Reader] B --> C{Chunking Logic} C -->|Batch 1| D[Rayon Worker 1] C -->|Batch 2| E[Rayon Worker 2] C -->|Batch N| F[Rayon Worker N] D & E & F --> G[Protobuf Serialization] G --> H[(ClickHouse DB)] H --> I[Grafana / SQL Insights] Prerequisites To follow along, you'll need: Rust (Stable) Tech Stack : quick-xml (for streaming), serde (serialization), rayon (data parallelism), and clickhouse-rs . A running ClickHouse instance. 1. Defining the Data Schema Apple Health data (specifically Record types) consists of types, dates, and values. Since we want high performance, we'll use Protocol Buffers to define our intermediate format, ensuring minimal overhead when moving data through the pipeline. // Simplified representation of a Health Record use serde ::{ Deserialize , Serialize }; #[derive(Debug, Serialize, Deserialize, Clone)] pub struct HealthRecord { #[serde(rename = "@type" )] pub record_type : String , #[serde(rename = "@startDate" )] pub
AI 资讯
Microservices vs monolith
Microservices have a marketing problem: they're associated with the engineering cultures of Netflix and Amazon, so ambitious teams assume adopting them is what serious companies do. But those companies moved to microservices to solve problems of enormous scale and huge headcount — problems you almost certainly don't have yet. For most products, splitting too early is one of the most expensive mistakes you can make. Here's the honest trade-off. What a monolith actually gives you A monolith is one deployable application. That simplicity is a feature, not a limitation, especially early: One codebase, one deploy. No orchestration, no service mesh, no distributed tracing just to understand a request. Simple debugging. A stack trace crosses your whole request. You're not correlating logs across five services to find one bug. Fast local development. Run the whole app on your laptop and iterate. Easy transactions. Data consistency is a database transaction, not a distributed saga you have to design and get right. The modern version isn't a big ball of mud. A modular monolith enforces clean internal boundaries — separate modules with clear interfaces — giving you much of the organization of microservices with none of the network overhead. What microservices actually cost Splitting into services doesn't remove complexity; it moves it from your code into the network, where it's harder to see and reason about. You inherit a long list of new problems: Distributed systems failure modes — partial failures, retries, timeouts, and eventual consistency become your daily reality. Data consistency across services — no more easy transactions; you're designing sagas and compensating actions. Operational overhead — every service needs deployment, monitoring, logging, and on-call. Slower local development and debugging — reproducing a bug can mean running half your architecture. For a small team, this overhead can consume the very velocity you were trying to gain. When microservices genuin
AI 资讯
LLM cost optimization for real products
LLM features are cheap to prototype and surprisingly expensive to run at scale. A demo that costs pennies becomes a five-figure monthly bill once real users arrive, because every request pays per token and it's easy to send far more tokens than you need. The good news: most AI bills are bloated, and a handful of tactics reliably cut them without users noticing any drop in quality. Right-size the model per task The most expensive mistake is using your biggest, smartest model for everything. Most work in a product doesn't need it. Route by difficulty: Small, fast models for classification, extraction, routing, and simple rewrites. Frontier models only for genuinely hard reasoning or high-stakes output. Implement a model router : a cheap first pass decides how hard the task is, and only the hard cases escalate to the premium model. This single change often cuts spend dramatically because the long tail of easy requests stops paying frontier prices. Cache aggressively Many requests are repeats or near-repeats. Don't pay twice: Exact-match caching — identical prompts return a stored response instantly and for free. A simple PostgreSQL or Redis lookup keyed on the request works. Prompt caching — most providers let you cache a large, stable prefix (system prompt, retrieved context) so you're only billed full price for the changing part. Semantic caching — for questions that are similar but not identical, match on embeddings and reuse an answer when confidence is high. Trim the tokens You pay for every token in and out, so waste is literal money: Compress prompts. Cut boilerplate, redundant instructions, and bloated few-shot examples. Shorter prompts that keep quality are pure savings. Retrieve less, better. In RAG, don't stuff twenty chunks in when three well-chosen ones answer the question. Re-rank and send only what's needed. Cap output. Ask for concise responses and set a max length; unbounded generations quietly inflate bills. Batch and stream For work that isn't real-t
产品设计
One of Meta’s Offices Was Briefly Overtaken by a Rogue Squirrel
The animal escaped after apparently arriving inside a package at Meta's Bangkok office, injuring one employee before finally being caught.
AI 资讯
Your Hand-Typed Slop Isn't Honest. It's Just Slower.
A post on X last week: "The fact that people can't even reply to posts without AI anymore says a...
开发者
Design não se faz sozinho: Friends of Figma mudou como eu vejo design
Abertura Eu sempre participei de comunidades de tecnologia: grupos de estudo do Google,...
创业投融资
Despite ‘misgivings,’ judge approves Elon Musk’s $1.5M SEC settlement
The saga of Musk's tussle with the SEC over how he disclosed his growing stake in Twitter (now X) has come to an end.
开源项目
Lovable reportedly in talks to double its valuation to $13.2B
The $300 million round is expected to be led by Menlo Ventures, Sifted reported.
AI 资讯
Meta is reportedly working on smart glasses that would be recording all the time
Meta might be the next company to make an always-on AI wearable. The company is working on prototype "super sensing" always-aware smart glasses that could continuously record audio and snap photos "every few seconds," according to the Financial Times. The wearer could then ask Meta AI about the captured audio and images. However, the images […]
AI 资讯
Expert Chase for iOS & Android
Where human life runs with AI Discussion | Link
AI 资讯
Did you ever face "stale singleton httpx connection" and "cold-start connection problem" problem, Well I did tonight.
It is been while I am learning and build around FastAPI. So there is a project where I was thinking how to add this new feature over exiting one. Like what changes I need to make in database which need to be reflected in my backend and frontend. I already lunched the web locally. Problem started When I when back to the web and reload it it shows this error: ERROR: ConnectTimeout: Unauthorized 401. I was like what? Why? I thougth there is some issue with login endpoint or refresh token function. When i did some debugging and found some new information which is: "Either Supabase's edge/pooler (or OS, or an intermediate proxy/NAT) silently kills those idle connections server-side after some timeout but client-side pool doesn't know that." As I was doing nothing in become idle state so to save the resources server side silently close that particular connection. So I came back and try to connect it give this error. First thought come it my mind after this was there should be a way to automatically check this idle state and if user was in ideal state then create a new connection. Proposed Solutions After a while I come up with these solution: Calculate the Idle time: if it is more then server connection timeout then establish new connection. Retry logic: retry once on the specific connection errors. I thought this will work but This again give me error then this new issue I faced. Cold-start connection problem There is something call dual-stack (IPv4 and IPv6) networks and Happy Eyeballs is a network mechanism which automatically move to IPv4 connection if IPv6 fails. But supabase-py uses httpx and it doesn't support Happy Eyeballs. So in first try after the connection time out it try to establish IPv6 connection which is not routeable in most Pakistani ISPs and ultimately it fails and wait for timeout. There is no way to try it again for IPv4. So we have to do it manually. So this error help me to learn many thing in process. Share your thoughts.
AI 资讯
Feds demand autonomous vehicle companies stop interfering with first responders
The National Highway Traffic Safety Administration said emergency scenes are not "edge cases."
AI 资讯
My favourite zsh/bash shortcuts (functions and aliases)
Introduction My zsh profile is over 1000 lines at this point. A lot of that is functions I asked AI to generate for me, since it's fast, portable, and saves me a ton of typing. Here's the thing though: the shortcuts that save me the most time aren't the clever ones. They're the dumb ones. Things like clone instead of git clone && cd , or dir instead of mkdir -p && cd . Each one only saves a second or two, but I run them so often that it adds up fast. These are in no particular order, just the ones I reach for constantly. Git aliases for common commands A few one-liners I have set up as plain aliases: alias gcp = "git cherry-pick" alias git-append = "git commit --amend --no-edit -a" gcp is self-explanatory. git-append amends the last commit with your currently staged (and unstaged, thanks to -a ) changes without touching the commit message. Great for fixing up a commit you just made before you push. Create a branch or switch to it if it already exists One of my most-used functions. Normally you have to remember whether a branch exists before deciding between git checkout <branch> and git checkout -b <branch> . This just does the right thing either way: gb () { if git rev-parse --verify --quiet " $1 " > /dev/null ; then git checkout " $1 " else git checkout -b " $1 " fi } Nuke all local changes to reset the working tree When an experiment goes sideways or I just want to throw everything away and start clean, I run nah : nah () { git reset --hard git clean -df if [ -d ".git/rebase-apply" ] || [ -d ".git/rebase-merge" ] ; then git rebase --abort fi } This resets tracked changes, removes untracked files and directories. No confirmation prompt, so use it carefully. Print recent commits as ready-to-paste cherry-pick commands Useful when you need to cherry-pick a batch of commits from one branch onto another in order: logs () { if [[ -z " $1 " || " $1 " = ~ [ ^0-9] ]] ; then echo "Usage: logs <number_of_commits>" return 1 fi git log -n " $1 " --reverse --pretty = format: "g
AI 资讯
"We cannot choose to become idiots": The AI cheating scandal roiling Brown University
AI cheating leads to "a failed society," professor says.
AI 资讯
OpenBSD Privilege Escalation, GitHub AI Agent Leaks, & CDN Supply Chain Risks
OpenBSD Privilege Escalation, GitHub AI Agent Leaks, & CDN Supply Chain Risks Today's Highlights This week's top security news features a critical use-after-free vulnerability in OpenBSD, a novel prompt injection attack leading to private repo leaks from GitHub's AI agent, and an unusual case of obfuscated bash scripts delivered via a CDN on consumer products. OpenBSD has a use-after-free allowing local privilege escalation to root (Hacker News) Source: https://nvd.nist.gov/vuln/detail/cve-2026-57589 A newly disclosed vulnerability, CVE-2026-57589, impacts OpenBSD, a renowned security-focused operating system. The vulnerability is identified as a use-after-free (UAF) flaw, which typically occurs when a program attempts to use memory after it has been freed, often leading to crashes or arbitrary code execution. In this specific case, the UAF bug allows for local privilege escalation to root. This type of vulnerability is particularly critical for operating systems, as it can enable an unprivileged attacker with local access to gain complete control over the system. System administrators and users of OpenBSD are advised to monitor official channels for patches and apply them immediately to mitigate the risk of compromise. Understanding the underlying cause of such UAFs is crucial for developing more robust memory management practices and identifying similar vulnerabilities in other systems. Comment: This is a critical reminder for OpenBSD admins to patch immediately, as use-after-free exploits are a classic, dangerous route to full system compromise from local access. GitLost: We Tricked GitHub's AI Agent into Leaking Private Repos (Hacker News) Source: https://noma.security/blog/gitlost-how-we-tricked-githubs-ai-agent-into-leaking-private-repos/ Researchers have uncovered a significant AI-specific security vulnerability, dubbed 'GitLost,' demonstrating how GitHub's AI agent can be manipulated to leak sensitive information from private repositories. The attack leverag
AI 资讯
Judge approves $1.5 million SEC-Musk settlement over Twitter investment
The opinion says whether it's fair is 'for our citizenry to decide at the ballot box.'
开发者
Try out IsItCrashing.com
Hi everyone! I recently launched IsItCrashing.com How often do you deploy a website only to discover later that: ❌ A page is returning a 404 or 500 error ❌ Images or assets aren't loading on some random pages ❌ A route is completely blank ❌ JavaScript crashes are breaking the page ❌ Customers find the problem before you do IsItCrashing.com helps you catch these issues before your users do. Simply enter your website URL, and the tool scans your site to identify: ✅ Broken pages (404/500) ✅ Broken links ✅ Missing assets ✅ Blank pages ✅ JavaScript errors ✅ Website health issues Get a clean, easy-to-read report so you can fix problems quickly and deploy with confidence. Whether you're a developer, QA engineer, agency, or website owner, IsItCrashing.com makes website testing faster and easier. try out here : 🌐 https://isitcrashing.com
AI 资讯
From Prompts to Pipelines: How I Use Agentic Coding as an Engineering Workflow
I am interested in agentic coding for the same reason I care about good engineering process in general: I want work to move forward in a way that is inspectable, repeatable, and resilient once the task gets messy. A lot of AI-assisted coding still feels like improvisation. You ask for something, get a result, adjust the prompt, try again, and hope the useful reasoning is still somewhere in the scrollback. That can work for tiny edits. It gets much less convincing when the task starts touching architecture, tests, review, or pull requests. What I want instead is a workflow where the model helps me think and execute, but inside a structure I can inspect afterwards. I want artifacts, gates, and something I can resume tomorrow without reconstructing the entire mental state from memory. That is why I use po8rewq/agentic-skills . It gives me a practical way to do agentic coding as an engineering workflow rather than as a long sequence of chat turns. A task moves through requirements, architecture, implementation, checks, review, and pull request creation. Each stage leaves something I can read, verify, and challenge. What makes this interesting to me The interesting part is not just that there is a CLI. Plenty of tools have a CLI. What matters to me is that it turns AI-assisted coding into a staged system: requirements force the task to become explicit architecture makes risks visible before code is written implementation happens against a plan instead of against a vague prompt checks and review happen as part of the flow, not as an afterthought runs are resumable, so interruptions do not destroy context That changes the feel of the work quite a bit. Instead of asking "what should I prompt next?", I am usually asking "what stage is this task in, and what should exist before I move on?" Where this really clicked for me was when I noticed I was spending less energy trying to preserve context in my head and more energy evaluating actual outputs. What the repository actually
AI 资讯
Stop writing a test-data builder for every class in .NET
If you've ever written test data by hand, you know the ritual: a PersonBuilder , an OrderBuilder , an AddressBuilder … one hand-written builder per class, each one a wall of WithX(...) methods you have to maintain forever. The Test Data Builder and Object Mother patterns are great — the boilerplate is not. XModelBuilder gives you a fluent builder for any C# class out of the box. No per-class builder required. It handles constructor parameters, init-only properties, read-only members, even private backing fields — via reflection, deterministically. Install dotnet add package XModelBuilder 30-second example You can use it fully standalone (no DI container) through a small static facade: using XModelBuilder.Default ; var order = For . Model < Order >() . With ( x => x . OrderDate , new DateTime ( 2026 , 7 , 1 )) . With ( x => x . Lines [ 0 ]. Product , "Widget" ) // deep paths + indexers just work . With ( x => x . Lines [ 0 ]. Quantity , 3 ) . Build (); No OrderBuilder , no OrderLineBuilder . The Lines[0].Product path drills into a nested collection element and sets it for you. Need a whole list? Create.Models<Order>(10) . Deterministic fakers, seeded once Random test data that changes every run is a debugging nightmare. XModelBuilder ships a seeded, dependency-free faker (and a Bogus integration if you prefer). Register it once: services . AddXModelBuilder () . AddXFaker ( seed : 12345 ); // reproducible values, every run Then let it fill in the noise while you set only what your test actually cares about: var order = xprovider . For < Order >() . With ( x => x . Id , p => p . XFake (). NewGuid ()) . With ( x => x . Customer . Name , p => p . Bogus (). Company . CompanyName ()) . With ( x => x . Lines [ 0 ]. Quantity , 3 ) . Build (); XFake().NewGuid("customer-acme") even gives you a stable GUID from a name — same key, same GUID, regardless of call order or parallelism. Deterministic by design. Build a whole list: BuildMany Need ten of something, each slightly differ