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Your order-processing Lambda starts sending duplicate confirmation emails. Not always — maybe one order in twenty. CloudWatch shows more invocations than messages published. The function code hasn't changed in weeks. What changed is that someone added a fraud check that pushed processing time from 25 seconds to around 45, and your SQS queue is still running the default 30-second visibility timeout. That combination is the whole bug. When a Lambda pulls a message from SQS, the message isn't deleted — it's hidden for the duration of the visibility timeout. If the function is still working when that window closes, SQS assumes the consumer died and hands the same message to another invocation. Now two Lambdas are processing the same order, both will "succeed," and both will send the email. Nothing errors. Nothing retries. There is no log line that says "this message was delivered twice because your timeouts are misconfigured." Infrawise ( npm ) flags this exact mismatch as a high-severity finding before it costs you an afternoon of staring at idempotency-free handler code. This post walks through why the bug is so hard to see, how the detection works, and how to keep an AI assistant from reintroducing it. Why you never catch this one yourself Three things make this misconfiguration nearly invisible: It passes every test. In local tests and staging, your handler processes a synthetic message in two seconds. The 30-second visibility window never comes close to expiring. The bug only exists under production conditions — real payload sizes, real downstream latency, cold starts stacking on top of slow dependencies. The defaults set the trap. SQS queues default to a 30-second visibility timeout. Lambda functions routinely get their timeout bumped to 60, 120, or 900 seconds as they grow. Nobody bumps the queue at the same time, because the two settings live in different consoles, different IaC resources, and usually different pull requests. The failure signature points elsewhe

Modern C# Features: A Deep Dive into Records, Pattern Matching, Async, and Performance A practical guide to the C# language features that have reshaped how we write .NET code — records, pattern matching, async/await improvements, nullable reference types, LINQ enhancements, Span<T> , and performance optimizations. Table of Contents Introduction Records Pattern Matching Async/Await Improvements Nullable Reference Types LINQ Enhancements Span<T> and Memory<T> Performance Optimizations Quick Reference Table Conclusion Introduction C# has evolved significantly since C# 8. Each release (9, 10, 11, 12, 13) has focused on three consistent themes: Conciseness — write less boilerplate to express the same intent. Safety — catch bugs at compile time instead of runtime (especially around null ). Performance — give developers low-level control without leaving the managed, safe world of .NET. This guide walks through the features that matter most in day-to-day development, with working code examples you can drop into a dotnet run project. 1. Records Introduced in C# 9 , record types give you immutable, value-based data models with almost no ceremony. Why records exist Before records, representing an immutable data object meant hand-writing a constructor, Equals , GetHashCode , ToString , and often a With -style copy method. Records generate all of this for you. // Before: a "plain" immutable class public class PersonClass { public string FirstName { get ; } public string LastName { get ; } public PersonClass ( string firstName , string lastName ) { FirstName = firstName ; LastName = lastName ; } public override bool Equals ( object ? obj ) => obj is PersonClass p && p . FirstName == FirstName && p . LastName == LastName ; public override int GetHashCode () => HashCode . Combine ( FirstName , LastName ); public override string ToString () => $"PersonClass {{ FirstName = { FirstName }, LastName = { LastName } }} " ; } // After: the same thing as a record public record Person ( stri

In-process cron ( node-cron , @nestjs/schedule , OS crontab) runs inside one Node process. That is fine for a single instance, but it does not survive restarts gracefully, deduplicate across replicas, or share infrastructure with your other background jobs. BullMQ stores queues and schedulers in Redis . Job Schedulers (BullMQ 5.16+) are the recommended way to enqueue recurring work on a cron pattern or fixed interval. The same workers that process one-off jobs also process scheduled ones, with retries, backoff, and concurrency you already get from BullMQ. This post covers Job Schedulers in plain Node.js, operations and pitfalls, a NestJS setup with @nestjs/bullmq , and a runnable demo with a fast cron heartbeat and a daily cleanup cron. Prerequisites Node.js version 26 Redis at redis://localhost:6379 (included in the demo docker-compose.yml , or use Postgres and Redis containers with Docker Compose ) npm i bullmq For the NestJS section: npm i @nestjs/bullmq bullmq BullMQ 2.0+ does not require a separate QueueScheduler instance. Use the Job Scheduler API ( upsertJobScheduler ), not the deprecated repeat option on queue.add() . Mental model Piece Role Queue Holds jobs waiting to run Worker Executes jobs Job Scheduler Factory that enqueues jobs on a schedule Scheduled job A job instance produced by a scheduler A scheduler id is stable across deploys. Calling upsertJobScheduler with the same id updates the schedule in place instead of creating duplicates. Queue and worker Share one Redis connection config between the queue and the worker: import { Queue , Worker } from ' bullmq ' ; const connection = { host : ' localhost ' , port : 6379 }; const queue = new Queue ( ' reports ' , { connection }); const worker = new Worker ( ' reports ' , async ( job ) => { console . log ( `[ ${ job . name } ]` , new Date (). toISOString (), job . data ); }, { connection }, ); worker . on ( ' failed ' , ( job , error ) => { console . error ( job ?. name , error . message ); }); Start the

We have all been there. You walk into a room full of tech enthusiasts, the ambient noise is humming...

A new study has succeeded in mapping, on a global scale, the fungal network that supports plant life and helps regulate our planet’s climate.

Hello, everyone. When listening to a conversation, we naturally keep track of who is speaking. A program has a harder job: beyond finding speech, it must also determine where one speaker gives way to another. Today, I will use an ONNX version of Pyannote Segmentation 3.0 to detect speaker changes in a two-person conversation and split the recording into one WAV file per utterance. What I Tested This lab uses FFmpeg to decode a roughly 14-second conversation into a 16 kHz mono waveform. It then combines the Pyannote segmentation model with simple post-processing to produce contiguous speaker segments. I wanted to verify: Whether six alternating utterances can be separated into six segments Whether the detected speaker indexes remain consistent throughout the recording Whether ONNX Runtime can process the audio faster than real time using only its CPU execution provider Whether every segment can be saved as a separate WAV file The complete code and reproducible environment are available in the pyannote-scd lab in kiarina/labs . This test performs segmentation using the model's speaker indexes. It does not compare speaker embeddings or run clustering, so it is not a complete speaker diarization pipeline that identifies the same person throughout a long recording. Reproducing the Lab You will need: mise uv FFmpeg curl The following commands fetch only this lab, download the shared test audio, and run it: git clone --depth 1 --filter = blob:none --sparse \ https://github.com/kiarina/labs.git cd labs git sparse-checkout set .gitignore .mise/tasks Makefile mise.toml \ 2026/07/04/pyannote-scd make download-test-assets mise -C 2026/07/04/pyannote-scd run On the first run, the task downloads the full-precision onnx/model.onnx file from onnx-community/pyannote-segmentation-3.0 on Hugging Face. uv then prepares the Python dependencies and runs the detector. How Speaker Segments Are Detected The input is this shared test asset: assets/mp3/conversation_2speaker_14s_16k.mp3 The re

🧠 Building CogneeCode - AI Developer Memory Assistant The Problem Every developer faces the problem of lost context. "Why did I make this decision 3 months ago?" "How did I fix this bug last week?" Current AI tools forget everything between sessions. This is a real problem that wastes hours of developer time. My Solution CogneeCode is an AI developer memory assistant that builds a permanent knowledge graph using Cognee Cloud . It remembers every decision, bug fix, and code context you give it. What It Does ✅ Log architectural decisions with tags and context ✅ Log bug fixes with error messages and solutions ✅ Ask natural language questions about your codebase ✅ Get answers with evidence citations from the knowledge graph ✅ Semantic search across all memories ✅ Visual timeline of all decisions and bug fixes ✅ Analytics dashboard showing memory insights ✅ Knowledge graph visualization Tech Stack Backend: Flask (Python) Memory Layer: Cognee Cloud LLM: Groq Llama 3.3 Frontend: Vanilla HTML + CSS + JS Icons: Tabler Icons Cognee Cloud APIs Used remember() - Save decisions and bug fixes with metadata recall() - Natural language queries with evidence citations search() - Semantic search across memories visualize() - Knowledge graph visualization improve() - Memory graph enrichment forget() - Remove outdated memories Why This Matters When you return to a project after months, all your reasoning and solutions are still there, searchable in natural language. No more "Why did I do this?" or "How did I fix this bug?" Demo Watch the video: https://youtu.be/TNcBIBuPW7c Links 🔗 GitHub: https://github.com/JOSESAMUEL14/cogneecode 🔗 Live Demo: https://josesamuel.pythonanywhere.com AI Assistance Disclosure Built with assistance from Claude and Gemini AI. Built for WeMakeDevs x Cognee Hackathon 2026 Category: Best Use of Cognee Cloud ⭐ Star the repo if you find it useful!

You did the hard part. You designed it, you built it, you shipped it. The product is good. And still, the users do not come. I have been in that exact spot more than once. You refresh the analytics, you tell yourself it is early, and quietly a worse question starts to form: what if people are not ignoring my app, what if they simply never see it? Here is the thing almost nobody tells builders in 2026. For a growing share of your future users, the front door to the internet is no longer a list of blue links. It is a sentence. Someone opens ChatGPT, Perplexity, or Google's AI Mode and types "what is the best tool for X." The model replies with a short list of names. If your product is not one of them, you do not exist in that moment. There is no page two to claw your way onto. There is one answer, and you are either in it or you are not. Three things are probably true about your app right now, and you cannot see any of them Your app might render blank to the machines that decide. If you built a single-page app (React, Vue, most modern stacks), the raw HTML a crawler receives can be an almost empty . Most AI crawlers do not run JavaScript. They read what your server sends and leave. To them, your beautiful app has no words, no product, no reason to be cited. You can rank number one on Google and still be missing from the answer. In one large 2025 study, roughly 68 percent of the pages cited in AI Overviews were not even in the top ten organic results. Ranking and being cited have quietly become two different games. Winning the old one no longer wins you the new one. A model may already be describing your product to strangers, and getting it wrong. A feature you do not have. A price that is out of date. A category that is not yours. You are being represented in rooms you will never enter, by a narrator you never hired, and the only way to fix the story is to give the machines a cleaner one to read. None of this shows up in your dashboard. That is what makes it dangerous

Artificial Intelligence has changed the way we write software, but one thing has become clear: AI is a collaborator, not a replacement. After using coding assistants for months, I've realized they're best at handling repetitive tasks: Generating boilerplate code Explaining unfamiliar APIs Refactoring existing functions Writing documentation Creating unit tests Finding bugs faster Where AI still struggles is understanding the bigger picture. It doesn't know your product vision, business requirements, or why one architectural decision is better than another. Those are still human problems. The most productive workflow isn't asking AI to build an entire application from scratch. It's treating AI like an experienced teammate that can help with implementation while you stay responsible for the design and direction. The developers who will thrive over the next few years won't necessarily be the ones writing the most code—they'll be the ones asking better questions, validating AI-generated solutions, and combining technical knowledge with critical thinking. AI is changing software development, but it's also raising the value of good engineering judgment. How has AI changed your development workflow? What's one task you now almost always delegate to an AI assistant?

Honestly it's not a new concept. this feature already existed in models before. problem was the models were just weak. Looping only works if each attempt gets the agent closer to the correct solution. Earlier models weren't consistent enough for that. They often misunderstood feedback, repeated the same mistakes, or got stuck in an infinite loop. Instead of improving with each iteration, they frequently failed to make meaningful progress, eventually consuming large numbers of tokens without solving the problem. The Context Window Limitation Earlier language models had much smaller context windows. As the agent went through more iterations, the conversation history and reasoning gradually filled the available context. Once the context window was exceeded, older messages had to be dropped or compressed into summaries. As a result, the agent could forget previous failed attempts, lose important clues or reasoning, and sometimes repeat the same mistakes it had already made. So what did modern models actually fix? Bigger context windows Models can now hold way more of the conversation/history without forgetting, so the agent doesn't need to spin up a fresh session every few iterations. it can just keep looping with the full history of what failed and why. modern models also got way more consistent earlier if you asked a model to fix the same bug 5 times you'd get 5 different half-baked answers, now it actually converges toward the real fix. and tool use got better too . Old models could write code but couldn't run it and read the actual error, now they call a test runner, see the real failure, and fix that exact thing which is literally what makes the "verify" step possible. And then there's inference it is simply the process of a model generating an answer. like when you type "write a java binary search," the model reads your prompt, thinks, and generates code that whole process is inference. every time the model generates text, that's one inference. now here's the thin

Hello, I'm Maneshwar. I'm building git-lrc, a Micro AI code reviewer that runs on every commit. It is...

When you fire a fetch() and the component that triggered it unmounts, the request keeps going. The server still processes it. When the response arrives, it calls back into whatever JavaScript it finds — a stale closure, a dead state setter, a global store that has already moved on. React's "Can't perform a state update on an unmounted component" warning is the polite version of this. The silent version is worse: results from an old query overwriting the current UI. These aren't mysterious race conditions. They're the predictable result of starting async work and never telling it to stop. The race condition hiding in every search box The search input is the clearest example. The user types "reac", your debounce fires a request. Before it lands, they finish typing "react" and you fire another. Two requests, in flight at the same time, and no guarantee about which one finishes first. If the "reac" request happens to be slower — network jitter, a cache miss, a heavier result set — it will land after "react" and overwrite the correct results with the wrong ones. The bug reproduces maybe one time in twenty on a local dev server, and consistently in production on a slow connection. The fix isn't smarter debouncing. It's cancelling the previous request when a new one starts. AbortController in plain terms AbortController is a browser-native API for cancelling async work. You create a controller, pass its signal to fetch() , and call controller.abort() to cancel. If the response hasn't arrived yet, the fetch promise rejects with an AbortError . const controller = new AbortController (); fetch ( ' /api/search?q=react ' , { signal : controller . signal }) . then ( res => res . json ()) . then ( data => setResults ( data )) . catch ( err => { if ( err . name === ' AbortError ' ) return ; // expected — not a real error setError ( err ); }); // Somewhere else, when we no longer need this request: controller . abort (); Two things to internalize: signal is how the controller knows

Hello, DEV Community! 👋 Hi everyone! My name is Sulemana Abdallah , and I'm excited to be part of the DEV Community. I'm passionate about software development and enjoy building modern, responsive web applications using: HTML CSS JavaScript TypeScript React Python My goal is to become a skilled Full-Stack Developer and Software Engineer while continuously learning and building real-world projects. I joined DEV to: Learn from experienced developers. Share my projects and progress. Write about what I learn. Connect with developers from around the world. I'm looking forward to growing with this amazing community. Thanks for reading! 🚀

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You can minimize the risk of films and shows being spoiled for you by muting comments, conversations, and keywords on various platforms.

AWS recently announced Amazon S3 Annotations, a feature that lets teams attach rich, searchable context such as summaries, classifications, compliance data, or AI-generated insights directly to S3 objects. Annotations can be updated independently of the object and queried across datasets, reducing the need for separate metadata systems. By Renato Losio