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If you have an interview in the next few hours and need to quickly revise Abstraction in C++ , this guide is for you. No long theory. No unnecessary examples. Only the concepts interviewers expect you to know. 📌 What is Abstraction? Definition Abstraction is the process of exposing only the essential behavior of an object while hiding unnecessary implementation details. Remember WHAT ↓ Hide HOW The user knows what an object can do, but not how it performs the work. ❓ Why Do We Need Abstraction? Without abstraction: Every developer needs to understand internal implementation. Client code becomes tightly coupled. Maintenance becomes difficult. With abstraction: Developers interact with a simple interface. Internal implementation can change without affecting users. Systems become easier to extend and maintain. Benefits ✅ Reduces complexity ✅ Promotes loose coupling ✅ Improves maintainability ✅ Supports extensibility ✅ Enables cleaner architecture ⚙️ How Does C++ Achieve Abstraction? C++ primarily achieves abstraction using: Abstract Class + Pure Virtual Functions + Runtime Polymorphism 🏗️ What is an Abstract Class? An abstract class is a class that contains at least one pure virtual function . It represents a: ✅ Contract ✅ Blueprint ✅ Common capability Because it is incomplete , it cannot be instantiated . 🎯 What is a Pure Virtual Function? Syntax virtual ReturnType functionName () = 0 ; Meaning It tells the compiler: Every concrete derived class must implement this function. = 0 does NOT mean "return zero." It simply marks the function as pure virtual . 🧠 Mental Model Think of it like this: Job Description ↓ Employee The job description defines responsibilities. Each employee fulfills those responsibilities differently. Or: Blueprint ↓ House You don't live inside a blueprint. You build a house from it. Similarly, you don't create objects of an abstract class—you create objects of concrete derived classes. 🏭 Practical Software Example Imagine an e-commerce application

Political operatives in Trumpworld hope that US Senate candidate Graham Platner stays in the race as long as possible.

Part 1 of "Trust the Machine" -> a series on building AI infrastructure that is secure, compliant, and governable by design. Most organizations can produce an accurate catalog of the web services they operate. Far fewer can produce an equivalent catalog of the AI systems they run — the models, fine-tunes, retrieval pipelines, agents, and third-party AI APIs now embedded throughout their products and internal tooling. This asymmetry defines the state of AI security in 2026. Adoption has outpaced oversight. Industry reporting this year has described a surge in enterprise AI activity on the order of 83% year over year, with governance and visibility lagging well behind. The consequence is a large and only partially mapped attack surface — one that many organizations cannot fully enumerate, let alone defend. Every mature security program rests on a single first principle: you cannot protect what you cannot see. Artificial intelligence is no exception. Before threat-modeling an agent or authoring a guardrail, an organization must be able to answer a deceptively difficult question: what AI is running across the environment, and who is accountable for it? This post examines how to build that answer. The rise of shadow AI Shadow IT — the unsanctioned adoption of tools outside official channels has been a recognized challenge for decades. Shadow AI is its faster-moving successor, and it appears in more forms than most inventories are designed to detect: Embedded API calls. A product team integrates a hosted model in a few lines of code and an API key, with no formal review. Copilots and assistants enabled across existing SaaS platforms, frequently activated by the vendor rather than the customer. Fine-tunes and adapters trained on internal data and stored in locations that fall outside standard scanning. Agents and automations that have incrementally acquired the ability to act—filing tickets, sending communications, initiating transactions—one permission at a time. Model de

In JavaScript and TypeScript, object references are often treated as disposable. An object is created, assigned to a variable, passed around, replaced, copied, spread, cloned, and eventually discarded. That is normal language behavior, but in larger mutable systems it creates a specific class of bugs: stale aliases. A stale alias appears when one part of the program still holds a reference to an old object while another part has already replaced that object with a new one. The old reference is still valid JavaScript, but it no longer points to current data. Hard Object References is a discipline for avoiding that class of bugs. The idea is simple: Object and array references should be stable. Do not replace them as a normal update mechanism. Copy data into existing objects instead. This rule is useful for application state, but it is not limited to global stores. It applies to ordinary variables, local component state, nested fields, arrays, drafts, snapshots, runtime models, and temporary objects. The broader principle is: Replace primitive values. Do not replace object and array references. The First Rule: const for Objects and Arrays The first level is variable bindings. If a variable holds an object or array, it should normally be declared with const : const user = { /* ... */ }; const items = [ /* ... */ ]; not: let user = { /* ... */ }; let items = [ /* ... */ ]; The point is not that the object becomes immutable. It does not. This is still possible: user . name = ' Alex ' ; items . push ( nextItem ); The point is that the variable should not be rebound to a different object: user = nextUser ; items = nextItems ; That replacement changes which object the variable points to. Any other code that still holds the old reference now points to obsolete data. So the first rule is: Use const for object and array references. Mutate or copy data into the object. Do not rebind the reference. This rule also applies to temporary objects. A temporary object may be short-live

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

The government has removed restrictions on Anthropic’s Fable 5 and Mythos 5 AI models—but there were strings attached.

Why AI programs at PE portfolio companies stall at the same organizational seam, and what to do about it. Blake Aber · Predicate Ventures · 2026 There's a failure mode I've watched play out at enough portfolio companies that I've given it a name: the ownership dyad. It goes like this. The AI program is running. The product manager owns the roadmap (what the AI should do). Engineering owns the deployment (how it does it). Both parties are competent. Both are aligned on the goal. And the AI initiative quietly stalls anyway, usually somewhere between the promising pilot and the production system that was supposed to follow. The mechanism is diffuse accountability at the decision layer. What the dyad looks like in practice In the average portco planning meeting, the PM and the engineering lead sit across from each other. The PM has a change request: "The model is producing summaries that miss the key clause in contracts above a certain length. We should fix this." Engineering hears this and wants to know: is this a prompt change or a model change? Either requires scoping, and scoping requires the PM's input on acceptable behavior. So engineering asks the PM. The PM says "whatever's best technically." Engineering ships a prompt change. The next month, the same issue appears in a different context. The PM brings it back. Neither person is wrong. Neither person is slacking. The problem is structural: there's no single person who can describe (precisely and completely) what the AI should produce, evaluate whether it's producing it correctly, and approve a change to the system without requiring the other party's sign-off. The dyad looks like shared ownership. It functions as diffuse accountability. No one is in charge of the model's behavior. The failure mode at month nine Most portco AI programs that make it through a successful pilot still die quietly around month nine of production. The most common reason is not that the model got worse. It's that the harness around the m

nginx Event Loop — Complete Lifecycle Reference A precise, bottom-up reference covering every buffer, syscall, interrupt, and data movement from the moment a TCP packet hits the NIC to the moment a response is sent back. Two concurrent users are used throughout as a concrete example. Table of Contents Foundations — fd and Socket Hardware Layer — NIC, DMA, Interrupts Kernel Structures and All Buffers epoll — How the Worker Waits Efficiently nginx Startup Sequence Complete Request Lifecycle — Two Concurrent Users What Happens While Worker is Busy All Buffers — Master Reference All Syscalls — Master Reference Failure Modes 1. Foundations 1.1 Everything is a File Linux's core philosophy: every I/O resource — files on disk, network connections, pipes, terminals, devices — is represented as a file. This means one unified API ( read , write , close ) works on all of them. The kernel manages the actual resource. Your process holds a token. 1.2 File Descriptor (fd) A file descriptor is just an integer . It is a per-process token that refers to a kernel-managed resource. The kernel maintains a table per process called the fd table — a simple array where the index is the fd and the value is a pointer into the kernel. Process fd table: ┌─────┬───────────────────────────────┐ │ fd │ points to │ ├─────┼───────────────────────────────┤ │ 0 │ stdin │ │ 1 │ stdout │ │ 2 │ stderr │ │ 3 │ listen socket (nginx) │ │ 5 │ User A client connection │ │ 6 │ User B client connection │ │ 12 │ backend connection for User A │ │ 13 │ backend connection for User B │ └─────┴───────────────────────────────┘ 0, 1, 2 are always pre-assigned. Application fds start from 3 upward. The fd is meaningless on its own. It only means something when passed to a syscall — the kernel uses it to look up the real resource. 1.3 Socket A socket is the kernel's internal data structure representing one end of a network connection. Created when your process calls socket() . Lives entirely in kernel RAM. Your process nev

Nvidia has dominated the AI chip market for years, but the era of total dependence might be ending. OpenAI just shared its plans to spice things up with Jalapeño, its custom inference chip built with Broadcom, joining Google, Apple, and SpaceX in a growing list of companies building their way out of single-supplier risk. The goal is less of a […]

Java LLD: Designing Snakes and Ladders with O(1) Move Resolution Designing Snakes and Ladders is a classic LLD (Low-Level Design) interview question that tests your ability to write clean, maintainable, and highly performant code. While the rules are simple, naive implementations quickly fall apart under scale, concurrency, or changing business requirements. Want to go deeper? javalld.com — machine coding interview problems with working Java code and full execution traces. The Mistake Most Candidates Make Expensive Runtime Scans : Iterating through lists of snakes and ladders on every single move, turning an $O(1)$ lookup into a slow $O(N)$ search. Violating SRP : Hardcoding board mechanics, game loops, and dice rolling logic inside a single monolithic class. Tight Coupling : Binding player movement directly to the dice, making it incredibly difficult to introduce custom game rules (e.g., crooked dice or extra turns). The Right Approach Core mental model : Treat the board as a flat, pre-computed $O(1)$ lookup array where each index represents a cell and its value represents the final destination. Key entities/classes : Board , Jump (representing Snakes/Ladders), Player , Dice , Game , and MovementStrategy . Why it beats the naive approach : It decouples board setup from game loop execution, turning expensive runtime lookups into instantaneous array access. The Key Insight (Code) public class Board { private final int [] board ; // Pre-computed jump destinations public Board ( int size , List < Jump > jumps ) { this . board = IntStream . range ( 0 , size + 1 ). toArray (); jumps . forEach ( j -> board [ j . start ()] = j . end ()); // Precompute O(1) lookups } public int resolvePosition ( int current , int roll ) { int next = current + roll ; return next < board . length ? board [ next ] : current ; } } Key Takeaways DP-Style Precomputation : Pre-populating a lookup array transforms runtime search complexity from $O(N)$ to $O(1)$ time complexity per turn. Open-Closed

Originally posted on https://symfonycasts.com/blog/honest-entities Your Doctrine entities are lying to you! For years, the standard way to build Doctrine entities in Symfony has looked something like this (and it's still what MakerBundle generates today): #[ORM\Entity] class ConferenceTalk { #[ORM\Id] #[ORM\GeneratedValue] #[ORM\Column] private ?int $id = null ; #[Assert\NotBlank] #[ORM\Column(length: 255)] private ?string $title = null ; #[ORM\Column(type: Types::TEXT, nullable: true)] private ?string $abstract = null ; public function getId (): ?int { return $this -> id ; } public function getTitle (): ?string { return $this -> title ; } public function setTitle ( ?string $title ): static { $this -> title = $title ; return $this ; } public function getAbstract (): ?string { return $this -> abstract ; } public function setAbstract ( ?string $abstract ): static { $this -> abstract = $abstract ; return $this ; } } At first glance, this looks perfectly reasonable. The title field is required. We know that because it has a NotBlank constraint and the database column is not nullable. But look closer. private ?string $title = null ; public function setTitle ( ?string $title ): static public function getTitle (): ?string According to the PHP type system, the title is optional. In fact, the public API of this class explicitly allows us to set it to null . That means this is perfectly valid: $talk = new ConferenceTalk (); And so is this: $talk = new ConferenceTalk (); $talk -> setTitle ( null ); Both objects represent a conference talk that can never be successfully persisted. Eventually, Doctrine catches the problem: $talk = new ConferenceTalk (); $entityManager -> persist ( $talk ); $entityManager -> flush (); // boom! SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'title' cannot be null The database knows that a conference talk must have a title. Our PHP code does not. So why do we build entities this way? Historically, this pattern was optimized for simpli

At high-stakes meetings with the White House, Anthropic's cofounder—a "weirdo," per one official—has been replaced by cofounder Tom Brown.

Trump administration officials tell WIRED that if Anthropic wants to rerelease Fable 5, it will need to ensure the model's guardrails can't be circumvented. Security experts say that can't be done.

Hello Dev Community! 👋 It is officially Day 26 of my journey to master the MERN stack! Today, I continued with Lecture 9 of Apna College's JavaScript playlist with Shradha Didi, transitioning from raw prototype object manipulation into modern ES6 structural design: Classes and Inheritance . Yesterday we saw how single objects share methods; today I learned how to create scalable blueprints to manufacture objects efficiently. 🧠 Key Learnings From JS Lecture 9 (Classes & OOP) I explored the professional layout of Object-Oriented Programming (OOP) in modern JavaScript: 1. What is a Class and a Constructor? A class is a standardized blueprint for creating objects. Inside every class, we can define a special method called a constructor() . The constructor triggers automatically the exact moment a new object is instantiated using the new keyword. It is the standard place to initialize instance properties dynamically. javascript class Car { constructor(brand, hp) { this.brandName = brand; this.horsepower = hp; } } let myCar = new Car("Toyota", 180); // Instantiates a fresh object instantly

Slack modernized its data platform by replacing SSH based execution in Amazon EMR pipelines with a REST driven orchestration layer called Quarry. The migration covered 700 plus Airflow operators, improving security, reliability, and observability while eliminating direct SSH access across production clusters and enabling a server side job lifecycle model. By Leela Kumili

"I don't prompt Claude anymore. My job is to write loops." — Boris Cherny, Claude Code creator Though I see where he's coming from, I'd put it differently. A developer's job isn't to write loops. It's to design state machines. Every major agent framework — Claude Code, Codex, Cursor, LangGraph — does the same thing under the hood. A while loop calls an LLM, checks if it wants to use a tool, runs the tool, repeats until done. The loop isn't just a solved problem. It's a boring problem. The hard part is everything around it. A loop has no idea what state the work is in. It just keeps going until something breaks or you run out of tokens. That's the Ralph Loop — named after the Simpsons kid who put a crayon in his nose. Agent, infinite loop, go. The Ralph Loop works, is famous, and has zero memory of where it is in the job. Like Ralph, it keeps going without knowing why. The Fix: A Finite State Machine Think about the NBA Finals. The Spurs and the Knicks aren't improvising — every possession has a state. Fast break. Inbound play. Half court set. Each one has specific reads and triggers for what happens next. Point guard De'Aaron Fox isn't making it up as he goes. The system tells him what situation he's in, and the situation tells him what to do. Your agent works the same way. You define the stages — planning, implementing, reviewing, error handling — and you define what triggers each transition. The agent doesn't orchestrate. It executes. One focused job per state. Why This Matters in Production When agents break, it's almost always one of three things: Infinite loops — one system repeated the same answer 58 times before anyone noticed. Context overflow — the history gets so long the model starts quietly forgetting things. Goal drift — 70 turns in, "don't touch auth" has completely evaporated. State machines fix all three. The loop runs until the list is empty, not until you run out of tokens. The goal lives in the transition logic, not in the context getting squeezed

The UFC event on the White House’s South Lawn is the president’s birthday gift to himself. Sources expect it to be a lobbying extravaganza.

The man who headed Trump’s invasions of US cities joined the US and European far right in Portugal to preach “remigration”—a plan to expel all minorities and immigrants.

Java LLD: Designing a Thread-Safe Parking Lot with Strategy Pattern Designing a parking lot is a staple of Java LLD and machine coding interviews, yet most candidates fail to write production-grade code. As an ex-FAANG interviewer, I've seen countless designs fall apart under concurrent traffic or when asked to support multiple slot allocation algorithms. If you're prepping for interviews, I've been building javalld.com — real machine coding problems with full execution traces. The Mistake Most Candidates Make Monolithic locking on the entire ParkingLot class: Using a global synchronized keyword on the entry method, which serializes all gate entries and destroys system throughput. Hardcoding slot-finding logic: Mixing spatial layout algorithms (like nearest-to-entrance or smallest-available-fit) directly inside the ParkingLot or Gate classes, violating the Open-Closed Principle. Thread-safety as an afterthought: Relying on raw List<Slot> iterations without synchronization, causing race conditions where multiple cars are assigned to the exact same physical slot. The Right Approach Core mental model: Decouple capacity management from slot selection by using a Semaphore for gate-keeping and the Strategy Pattern for thread-safe slot allocation. Key entities: ParkingLot , Gate , Slot , Vehicle , ParkingStrategy ( SmallestFitStrategy , NearestEntranceStrategy ), and StrategyFactory . Why it beats the naive approach: It isolates concurrency concerns (preventing overbooking) from business rules (how we choose a slot), making the system highly performant and easily extensible. The Key Insight (Code) public class EntryGate { private final Semaphore semaphore ; private final ParkingStrategy strategy ; public EntryGate ( int capacity , ParkingStrategy strategy ) { this . semaphore = new Semaphore ( capacity ); this . strategy = strategy ; } public synchronized Ticket park ( Vehicle vehicle ) { if (! semaphore . tryAcquire ()) throw new ParkingFullException (); Slot slot = strat

“Republicans are just going to have to suck it up and get it done,” says one Trump aide about the funding melee. The votes, though, may simply not be there.