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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

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

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

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

The animal escaped after apparently arriving inside a package at Meta's Bangkok office, injuring one employee before finally being caught.

A post on X last week: "The fact that people can't even reply to posts without AI anymore says a...

Abertura Eu sempre participei de comunidades de tecnologia: grupos de estudo do Google,...

It's more of a baa-ter arrangement.

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.

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 […]

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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.