标签：#rive

The electric-auto maker will officially debut its steering-wheel-free robotaxi on Thursday. But building the vehicle is the easy part.

Short answer: make the event identity durable, deduplicate at the consumer boundary, and resume from a server-issued cursor; a client-side set alone cannot make a marketplace chat room survive reconnects or an incident-response burst. The constraint is trust. A browser reconnects after a laptop sleeps, a mobile radio changes networks, or a tab is restored from the back-forward cache. It may replay its last request, lose an acknowledgement, or present an event twice. In an incident response dashboard, the same mechanics become dangerous at scale: an alert that appears twice can page two people, while a missing alert can hide the incident. I design the storage boundary first, because a pretty WebSocket demo does not answer either question. Start with an event identity that can outlive a connection Every published event needs an immutable identity scoped to the stream, not to a socket. For a marketplace chat room, I use (room_id, sequence) as the primary key and keep a globally unique event_id for tracing. The sequence is allocated by the room writer, so two reconnecting clients can compare progress without trusting wall-clock timestamps. The payload is deliberately boring. It includes the room, sequence, event ID, type, and data. A client can verify that an event belongs to the room it requested; it cannot mint a higher sequence or widen its token scope. That last rule matters more than transport choice. from dataclasses import dataclass from typing import Any @dataclass ( frozen = True ) class ChatEvent : room_id : str sequence : int event_id : str event_type : str data : dict [ str , Any ] def identity ( event : ChatEvent ) -> tuple [ str , int ]: """ The room sequence is the replay-safe identity. """ return event . room_id , event . sequence Do not use a payload hash as the only key. Two legitimate messages can have identical text, and a producer retry can produce different JSON ordering. Persist the identity and the payload together, with a uniqueness constraint,

New York's prestigious-yet-secretive venture firm Thrive Capital finally speaks out about its involvement in the messy drama upending international soccer.

Hello everyone. Scala's a programming language I've enjoyed learning on the side not only because I think it's stylish but because it's made me a better developer. Some of the gripes you encounter once you try to go intermediate or beyond, it's the Typelevel stack complexity. You just want to bootstrap a server and start writing some routes, and tbh sometimes the docs aren't that friendly. That's why I wrote Scala 3 Domain Design & Typelevel Stack Cookbook — a book that teaches some DDD in Scala and gives you some recipes to get you started on the stack (cats, cats-effects, fs2, http4s). It's a WIP currently at 40%. You can read a couple of chapters for free in leanpub: https://leanpub.com/scala3-domain-typestack-dev

The JVM ecosystem offers a wide range of powerful frameworks, each with its own strengths and capabilities. In a modern distributed architecture, however, applications are not always built using the same framework. Services developed with frameworks such as Quarkus, Micronaut, and Spring Boot may need to communicate seamlessly as part of the same system. This guide demonstrates how RabbitMQ can enable cross-framework asynchronous communication between JVM applications. We will build two applications using different frameworks: a Quarkus application that publishes LeaveRequest messages and a Micronaut application that consumes and processes them. The first application, built with Quarkus, publishes a LeaveRequest object as a message to RabbitMQ. The second application, built with Micronaut, receives the LeaveRequest message and processes it according to the application's business logic. By the end of this guide, you will have a practical understanding of how two applications built with different Java frameworks can communicate asynchronously using RabbitMQ. Lets begin the journey To ensure that both applications use a consistent message contract, create a separate Gradle project named common. This project will contain the shared LeaveRequest model and can be referenced as a dependency by both the Quarkus and Micronaut applications. @Introspected @Serdeable public record LeaveRequest ( String personName , String personRole , String facilityName , String wardName , String shiftName , String leaveReason , String recipientName , String recipientEmail , String recipient , String subject ) {} The dependency on the common project will be dependencies { annotationProcessor ( "io.micronaut:micronaut-inject-java:5.1.12" ) implementation ( "io.micronaut.serde:micronaut-serde-jackson:3.1.1" ) } The @Introspected and @Serdeable annotations enable Micronaut to generate the metadata required for efficient introspection and serialization. Connecting Quarkus to RabbitMQ To connect th

A practical guide to building reliable event-driven systems in Go using Apache Kafka. Learn how to implement tiered retry strategies with delayed reprocessing, route permanently failed messages to dead letter queues in Golang with Sarama. Prerequisites What do you need to follow along? Working knowledge of Golang. Go & Docker installed on your PC. What is an Event-Driven Architecture? An Event-Driven Architecture (EDA) is a design approach where services communicate by producing and responding to events. Each service operates independently, producing or reacting to events as they happen. What are Events? An event is a record of something that has happened in a system, typically representing a state change or a significant action. An event contains data (payload) describing what happened. An example of an event could be: A user signing up for a service. A user placing an order in your system. Components of an Event-Driven Architecture To understand how events flow through a system, we need to know three key players: Event Producers : They are the sources of events. They generate and publish events like signup events, order placed events, etc. Producers generate events and transmit them to the rest of the system. They do not know who is listening for or handling the events. Event Brokers : They sit between producers and consumers, decoupling them so neither needs a direct connection to the other. Brokers receive event messages, maintain their chronological order, make them available for consumption, and route them to the right consumers. Apache Kafka is an example of an event broker, and it's the one we'll use throughout this guide. Event Consumers : They handle the processing tasks. They listen on event channels and react when an event they are subscribed to is published, then they process the event, which can include making API calls, updating a database, triggering other events, or logging information. The Complete Flow With those three pieces in place, the flow of

The AI opportunity is huge, but "it would also be a grave error in our minds to let excitement weaken our investment discipline," Kushner warns in his first-ever investment letter.

JioHotstar explains the distributed architecture behind its real-time ad request workflow, covering ad decisioning, waterfall tiering, pacing algorithms, latency optimization, and service coordination required to select and deliver personalized advertisements during streaming playback at scale. By Leela Kumili

River plans to build a new factory, launch additional models from 2027, and target profitability as it scales production.

Why do simple features suddenly require cross-team negotiations? In this article, explore how boundary drift quietly destroys change locality and increases cognitive load across teams. Learn practical sociotechnical strategies - redistributing mechanics, exposing essential policy, and rehearsing exception paths - to restore domain boundaries and enable a truly evolutionary software architecture. By Michael Fischer, Nicholas Lawrence, Monica Karekar

By Randal L. Schwartz, and a few million TPU cycles Motto: "With the rigor of Bloc and the flex and speed of Signal" Why You Don't Have to Tear Up Your Codebase to Enjoy the Speed of Synchronous Signals If you have followed my talks, articles, or comments in the Flutter community over the years, you know I have been a strong advocate for Riverpod . Riverpod solved many of the fundamental global-state scoping issues inherent in classic InheritedWidget patterns, providing compile-safe dependency injection and clean state isolation. However, as the Flutter ecosystem evolved toward Riverpod 3 , I grew increasingly wary of the direction being pushed: a heavy reliance on mandatory code generation ( @riverpod annotations, build_runner, macros). Code generation introduces build-step friction, bloats compile times, and makes debugging generated syntax opaque. On the other side of the tracks sat BLoC . While I appreciated BLoC's structured, predictable event-to-state machine pattern ( on<Event> ), I was never a big fan of classic BLoC's reliance on underlying Dart Streams . Streams operate asynchronously via microtask queues—introducing subtle frame-rendering latency—and require extensive stream-transformer ceremony for simple state updates. Then came Signals (specifically Rody Davis's signals package). Signals brought raw speed, zero microtask overhead, fine-grained composable reactivity, and pure Dart portability. That realization birthed BlocSignal : combining BLoC's disciplined, enterprise event-state architecture with Signals' synchronous reactivity. And more importantly, it solved the single biggest pain point in Flutter development: the migration trap . 🚂 The Core Metaphor: "Switching Tracks in BlocSignal" In Flutter development, choosing a state management tool often feels like choosing a railroad company. If your team built an application on package:provider or flutter_bloc and wants to adopt Riverpod or Signals, traditional wisdom dictates a nightmare: tearing up al

It starts at just under $25,000, but the hybrid won't arrive until next year.

Event-Driven Architecture (EDA) is one of the most popular approaches for building scalable distributed systems. Instead of tightly coupling services through synchronous APIs, services communicate by publishing and consuming events. It sounds perfect. Until your consumers start making API calls for every event they receive. At that point, you've reintroduced the very coupling Event-Driven Architecture was supposed to eliminate. This is where Event-Carried State Transfer (ECST) comes in. The Hidden Problem in Event-Driven Architecture Imagine an e-commerce platform. A customer places an order. The Order Service publishes an event: { "event" : "OrderCreated" , "orderId" : "ORD-10234" } Several services subscribe to this event: Inventory Service Notification Service Analytics Service Shipping Service Billing Service Everything looks asynchronous. But here's what actually happens. Order Created Event │ ▼ Inventory Service │ GET /orders/ORD-10234 │ Order Service Notification Service does the same. Analytics Service does the same. Shipping Service does the same. Suddenly, one event generates dozens of synchronous API calls. Congratulations, You've Recreated a Monolith Your architecture now looks like this: Order Service ▲ ┌───────────┼───────────┐ │ │ │ Inventory Shipping Notification │ │ │ └───────────┼───────────┘ API Requests Although events are being used, every consumer still depends on the Order Service. If the Order Service is unavailable: Notifications fail Inventory updates fail Analytics stop processing Shipping cannot continue The event broker isn't the bottleneck anymore. The originating service is. Event-Carried State Transfer Solves This Instead of publishing only an identifier, publish the data consumers actually need. Instead of this: { "event" : "OrderCreated" , "orderId" : "ORD-10234" } Publish: { "event" : "OrderCreated" , "orderId" : "ORD-10234" , "customerId" : "USR-1001" , "customerName" : "John Doe" , "totalAmount" : 249.99 , "currency" : "USD" , "i

Installing Apache Kafka 4.2 on Ubuntu 24.04 (WSL2) Using KRaft Mode: A Complete Step-by-Step Guide Learn how to install Apache Kafka 4.2 in KRaft mode, understand its architecture, create topics, produce and consume messages, and troubleshoot common configuration issues—all without ZooKeeper. 🚀 Introduction Apache Kafka has become the de facto standard for building event-driven , real-time , and high-throughput applications. Whether you're processing millions of financial transactions, collecting application logs, streaming IoT sensor data, or connecting microservices, Kafka provides a scalable and reliable messaging platform. Until recently, setting up Kafka required running Apache ZooKeeper alongside Kafka brokers. While powerful, ZooKeeper added operational complexity and introduced another distributed system that administrators had to manage. Beginning with recent Kafka releases, KRaft (Kafka Raft Metadata mode) removes this dependency by allowing Kafka to manage its own metadata internally. This makes installation simpler, reduces operational overhead, and improves scalability. In this guide, we'll install Apache Kafka 4.2 on Ubuntu 24.04.4 LTS (WSL2) , configure a single-node KRaft cluster, and walk through the complete lifecycle: Installing Kafka Understanding the Kafka architecture Configuring KRaft mode Starting the broker Creating topics Producing and consuming messages Troubleshooting common issues Understanding the purpose of each configuration parameter Rather than simply listing commands, I'll explain why each step is necessary so that you understand how Kafka works under the hood. What is Apache Kafka? Apache Kafka is a distributed event streaming platform designed to move data reliably and efficiently between applications. Instead of applications communicating directly with each other, they communicate through Kafka. A producing application writes messages to Kafka. Kafka stores those messages reliably. One or more consuming applications read those m

In this article, we're going to explore Event Schema evolution with Event versioning 10. Event Schemas Will Eventually Change No event schema stays the same forever. As businesses grow, regulations shift, products gain new features, and processes become more complex, the data shared between services must evolve as well. This evolution is not optional—it is a natural consequence of a system adapting to changing requirements. Many teams initially assume they can simply update an event whenever needed. This assumption may hold when there is only one producer and one consumer, but real-world systems rarely remain that simple. Over time, multiple consumers emerge, each with its own responsibilities and release cycles. A typical system often looks like this: OrderConfirmed | +------------------+-------------------+ | | | v v v Inventory Billing Notification | v Analytics | v Customer Insights Each consumer evolves independently. Some services may deploy updates weekly, while others might release changes quarterly. In some cases, consumers may even belong to external teams with entirely different priorities and timelines. Because of this, producers cannot assume that all consumers will upgrade simultaneously. Schema evolution, therefore, is not just about modifying data structures. It is fundamentally about maintaining compatibility across independently evolving systems. Compatibility Is More Important Than Version Numbers When discussing schema evolution, teams often focus immediately on versioning. While versioning is useful, compatibility is far more critical. Without compatibility, versioning alone cannot prevent system breakage. Consider the following event: { "orderId" : "ORD-1001" , "customerId" : "CUS-501" , "totalAmount" : 249.99 } Now imagine a new requirement introduces currency. One approach might replace the existing field entirely: { "orderId" : "ORD-1001" , "customerId" : "CUS-501" , "amount" : { "value" : 249.99 , "currency" : "USD" } } Although the data mo

Interactive Rive mascots can react, think, talk, and connect to real AI, SaaS, web, and mobile products. Your SaaS Mascot Should Do More Than Just Sit There 👀 A lot of products have mascots. They look great on landing pages. Maybe they wave. Maybe they blink. Maybe there is a small looping animation. And that's it. But I think a product mascot can do much more. What if your mascot actually knew what was happening inside your product? That's the idea I've been exploring with Mascot Engine . I don't just want to animate characters. I want to build interactive mascot systems that connect to real products . From a mascot animation to a product system Imagine you're building an AI app. A user opens the app. The mascot is idle . The user sends a message. The mascot starts thinking . The AI begins responding. The mascot switches to talking . The task completes. The mascot celebrates . Something goes wrong? The mascot reacts to the error . The flow could look like this: User Action ↓ Product State ↓ Runtime Input ↓ Rive State Machine ↓ Mascot Reaction This isn't a video. It isn't a GIF. It isn't a pre-rendered animation playing randomly. The product controls the mascot at runtime. That's where things become interesting. A mascot can understand product states Well... not literally understand them 😄 The application still owns the logic. But we can expose a small runtime contract from the Rive file. For example: emotion = 2 isTalking = true lookX = 40 lookY = -10 celebrate = trigger error = false The developer controls these values from the application. The Rive State Machine handles the character behavior. The application controls what happened . The mascot system controls how the character reacts . I really like this separation. Why I use Rive for interactive mascots Traditional animation tools are great for videos and motion design. But product animation has different requirements. The character needs to react to application events. The animation may need runtime values. De

If you need real-time BTC conversion (USD and BRL), polling an API every few seconds is usually not enough. A better approach is streaming quotes with WebSockets and calculating conversions as events arrive. Why WebSockets for BTC conversion? With WebSockets, your app keeps one open connection and receives new prices instantly. Benefits: Lower latency than polling Fewer HTTP requests Better user experience for real-time values Trade-offs: You must handle reconnects Need heartbeat/health checks Must validate and normalize incoming messages Real-time conversion model For BTC conversion, a common model is: Stream BTC/USD Stream USD/BRL Calculate BTC/BRL = BTC/USD × USD/BRL This avoids waiting for a separate BTC/BRL endpoint and keeps conversion logic transparent What is a “tick”? A tick is one market update event. Example: BTCUSD changed to 64210.50 at timestamp t . In this article, each tick has: pair : market identifier ( BTCUSD , USDBRL ) price : latest value for that pair ts : event timestamp Why this matters: conversion state should always be derived from the latest ticks . Minimal WebSocket client (TypeScript) This client only transports responsibilities: Connect Receive messages Parse and normalize into a consistent shape Notify listeners Reconnect on disconnect type MarketTick = { pair : string ; // e.g. "BTCUSD" or "USDBRL" price : number ; ts : number ; }; class WsFeedClient { private ws ?: WebSocket ; private listeners : Array < ( tick : MarketTick ) => void > = []; constructor ( private readonly url : string ) {} connect () { this . ws = new WebSocket ( this . url ); this . ws . onopen = () => console . log ( " [ws] connected " ); this . ws . onmessage = ( event ) => { try { const data = JSON . parse ( String ( event . data )); // Normalize external payload into internal contract const tick : MarketTick = { pair : String ( data . pair ), price : Number ( data . price ), ts : Number ( data . ts ), }; // Basic guard if ( ! tick . pair || Number . isNaN ( tick

At my workplace, I worked on an ERP platform used by fashion businesses to manage customers, body measurements, products, orders, invoices, inventory, staff, and other day-to-day operations. Each business also had a public storefront where customers could browse products and check out. The storefront started as a simple sharing feature. Businesses could publish products, copy a link, and send it to customers outside the main workspace. That worked well because the storefront was mostly a product catalogue, and most of the sales process still happened after the customer contacted the business. As the platform evolved, the storefront became much more than a catalogue. Customers were discovering businesses through shared links, browsing products, placing an order, and tracking orders directly from the storefront. That introduced new technical requirements around branded storefronts, SEO, server-rendered metadata, public checkout, pricing, and analytics. This article explores how I designed the storefront around wildcard subdomains, immutable shop identities, server-side shop resolution, and a scalable analytics pipeline. Table of Contents Giving the Storefront Its Own Identity Business Names, Reserved Names, and Subdomains Resolving a Storefront Active and Inactive Storefronts Location and Currency Product Pages and Share Previews Storefront Event Ingestion Processing Raw Events Counting Unique Visitors With HyperLogLog Domain Routing and Local DNS 1. Giving the Storefront Its Own Identity The original storefront was fairly simple. It was a React application that fetched a business and rendered its products. Beyond that, there wasn't much to it. There were no branded storefronts, analytics, subdomains, or even a separate identity beyond the business itself. Introducing those capabilities meant the storefront needed its own data model. I introduced a dedicated shop entity to represent the public storefront. The business remained the source of operational data such as cu

The RabbitMQ upgrade looked like a straightforward infrastructure task: move from RabbitMQ 3.X to 4.X, provision the new broker, review the client setup, confirm queues still declare correctly, restart consumers, watch the logs, and move on. But infrastructure upgrades rarely test only infrastructure. They also test the assumptions your application has been making for years. In this case, the upgrade forced a more important question: is our messaging system reliable by design, or has it simply been relying on stable conditions? That distinction matters because a message queue can appear healthy when the broker is running, the network is stable, consumers are alive, and messages are acknowledged quickly. But production systems are not judged only by how they behave when everything is fine. They are judged by how they behave during restarts, closed channels, slow handlers, bad configuration, deployment windows, and partial failure. The RabbitMQ upgrade exposed those edges. It revealed assumptions around connection lifecycle, acknowledgements, dead-letter routing, retry behavior, observability, and operational simplicity. The real lesson was not just how to upgrade RabbitMQ. The real lesson was how to build a messaging layer that is easier to operate, easier to reason about, and safer to fail. Simplicity Is an Operational Feature One of the first things the upgrade exposed was complexity. Over time, messaging code can quietly become a small internal framework. A connection helper becomes a connection manager. A consumer wrapper becomes a consumer framework. Retry helpers appear, dead-letter helpers appear, failure handlers appear, and monitoring logic gets layered on top. Each addition may have been reasonable when introduced, but during an incident, complexity has a cost. Every abstraction becomes another place to inspect. Every helper becomes another assumption to validate. Every unused file becomes a possible source of false confidence. RabbitMQ integration code doe

Agentic testing is an AI-driven approach to end-to-end test automation introduced by Slack engineering. It uses AI agents that execute workflows based on intent rather than fixed scripts, adapting to UI and system changes at runtime. The approach aims to reduce brittle tests in distributed systems while complementing deterministic unit, integration, and E2E testing strategies. By Leela Kumili