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Protocol adapters are one of the easiest places for agent-commerce architecture to drift. An adapter begins with the narrow responsibility of translating an external protocol request into something the commerce platform understands. For example, an MCP-style tool may ask for return terms, an ACP-style interaction may ask whether checkout can be prepared, an AP2-related flow may carry payment authority information, and an internal feed may publish product capabilities. Those are adapter concerns at the boundary. The problem starts when the adapter does more than translate. It checks product availability from catalog fields. It interprets policy text. It decides whether checkout is ready. It treats a payment artifact as authority. It turns a domain blocker into a softer protocol response. Each shortcut may solve an integration problem locally, but it also creates a second place where commercial meaning is decided. When several adapters exist, those local decisions begin to diverge. The MCP tool may block return-policy quotation, the ACP adapter may expose the product as purchasable, the feed may publish it as checkout-ready, and the AP2-related flow may reject delegated payment. At that point, the platform does not only have multiple integrations. It has multiple interpretations of the same commercial state. This is the adapter problem in agent-ready commerce: semantic drift at the protocol boundary. The adapter should know how to speak the protocol. It should not decide product truth, policy meaning, eligibility, checkout validity, or payment authority. Those decisions belong inside the commerce platform, where they can be shared, tested, evidenced, and audited. This is the fifth article in the Agent-Ready Commerce series. Part 1 introduced the broader architecture model: Facts → Eligibility → Authority → State transition → Evidence → Audit Part 2 focused on commercial truth. It argued that catalog data is not enough. A platform needs source-backed, freshness-aware p

Aprenda a substituir o velho Cron por systemd timers para ganhar logs nativos, controle de dependências e maior robustez.

Most engineers don't think seriously about Kafka partitioning until something breaks in production. A topic that worked fine at low volume starts falling behind. Events that should be in order aren't. All of it traces back to a partitioning decision that was made quickly and never revisited. Why Partitioning Actually Matters Partitions are the unit of parallelism in Kafka. Every consumer in a group is assigned one or more partitions, and it processes those partitions alone. No two consumers in the same group share a partition. That means your partition count sets a hard ceiling on how many consumers can work in parallel: if you have 6 partitions, the 7th consumer in your group sits idle no matter how much load you're under. Partitioning also controls ordering. Within a single partition, events are strictly ordered. Across partitions, there are no guarantees. So how you distribute events across partitions determines what ordering guarantees your consumers can actually rely on. Get this wrong and you'll spend a long time debugging why events from the same user are being processed out of sequence. The partition key controls both of these things. It determines which partition an event lands in, and that decision has consequences that are expensive to reverse. Partitioning Strategies Partition by Key This is the most common strategy and the right default when ordering matters. You supply a key when producing an event, Kafka hashes it using the murmur2 algorithm, and takes the modulo against the partition count to decide where it lands. producer . send ( ' orders ' , key = b ' user_4821 ' , value = event ) Every event with the same key always lands in the same partition. That's what guarantees ordering within a key. All events for user_4821 go to partition 3 (or wherever the hash resolves), and your consumer reads them in the exact sequence they were produced. I default to this for almost everything I build now and only go keyless when I have a specific reason to. Use key

I had arrived at the final frontier. My bare-metal kernel was booting in QEMU, driving NVMe block storage, running multi-agent swarms, and rendering a force-directed canvas. But to make V.E.L.O.C.I.T.Y.-OS a truly next-generation system, I needed to close the loop: the operating system had to be able to evolve and compile itself without human intervention. The V.E.L.O.C.I.T.Y.-OS 12-Part Roadmap We are building a bare-metal, self-healing operating system running entirely inside the CPU's L3 cache. Here is the roadmap for this 12-part series: Part 1: The Spark — Exposing the "Safe-Room" security leak and building the compiler gate. Part 2: The NDA Language — Designing a content-addressed triplet representation to cure context bloat. Part 3: Ditching the Web Stack — Building a native 30MB IDE with 1,500,000x IPC latency drops. Part 4: The Closure JIT — Compiling AST blocks to nested closures and bypassing borrow checker limits. Part 5: JIT Math Optimizations — Replacing division operations with precomputed 16-bit lookup tables. Part 6: x86-64 Assembler & SCEV-Lite — Compiling scalar loops directly to native code in constant time. Part 7: Classic Compiler Passes — Implementing inter-procedural Dead Code Elimination and loop unrolling. Part 8: Reclaiming Ring 0 — Exiting UEFI boot services and transitioning the kernel to Ring 0. Part 9: Bare-Metal Drivers — Writing a PCI scanner, NVMe block storage controller, and FAT32 parser. Part 10: Synaptic Canvas — Rendering a spatial, force-directed GUI based on model token activation vectors. Part 11: Swarms & Hot-Patching — Building multi-agent scheduling and zero-downtime RCU driver updates. Part 12: Self-Evolution — Handing system control over to a local LLM Terminal that self-optimizes via telemetry. (You are here) During the final hours of my Sunday morning sprint, I completed the self-healing loop, the Biosphere P2P registry, and the Boot-to-NDA LLM Terminal handover. To achieve self-healing, I built a Ring 0 telemetry sys

With the Synaptic Canvas GUI rendering, my bare-metal kernel was fully functional. However, as I expanded the OS features, I ran into multitasking bottlenecks: how do I run background compilation, model inference, and GUI rendering concurrently without crashing the system? Last night, I solved this by implementing three core infrastructure services: Nexus Swarms , Beacon Headless Streaming , and Zero-Downtime OTA Hot-Patching . The V.E.L.O.C.I.T.Y.-OS 12-Part Roadmap We are building a bare-metal, self-healing operating system running entirely inside the CPU's L3 cache. Here is the roadmap for this 12-part series: Part 1: The Spark — Exposing the "Safe-Room" security leak and building the compiler gate. Part 2: The NDA Language — Designing a content-addressed triplet representation to cure context bloat. Part 3: Ditching the Web Stack — Building a native 30MB IDE with 1,500,000x IPC latency drops. Part 4: The Closure JIT — Compiling AST blocks to nested closures and bypassing borrow checker limits. Part 5: JIT Math Optimizations — Replacing division operations with precomputed 16-bit lookup tables. Part 6: x86-64 Assembler & SCEV-Lite — Compiling scalar loops directly to native code in constant time. Part 7: Classic Compiler Passes — Implementing inter-procedural Dead Code Elimination and loop unrolling. Part 8: Reclaiming Ring 0 — Exiting UEFI boot services and transitioning the kernel to Ring 0. Part 9: Bare-Metal Drivers — Writing a PCI scanner, NVMe block storage controller, and FAT32 parser. Part 10: Synaptic Canvas — Rendering a spatial, force-directed GUI based on model token activation vectors. Part 11: Swarms & Hot-Patching — Building multi-agent scheduling and zero-downtime RCU driver updates. (You are here) Part 12: Self-Evolution — Handing system control over to a local LLM Terminal that self-optimizes via telemetry. 1. The Nexus Core Swarm Runtime ( nexus.rs ) To support concurrent compilation and optimization, I built the Nexus Core Swarm Runtime . The

A product page is not a contract. It is a presentation surface. That distinction matters more once AI agents start interacting with commerce systems. Traditional ecommerce platforms can rely on human interpretation. A human can read a product title, inspect images, compare delivery notes, scan a return policy, notice uncertainty, and decide whether to continue. A product page can be visually useful even when the underlying commercial state is incomplete, stale, or spread across several systems. An AI agent needs a different interface. It should not need to scrape a product page, infer policy meaning from free text, guess whether inventory is fresh, or decide whether a price is reliable enough to quote. If the platform expects agents to recommend products, compare alternatives, prepare checkout, or act within delegated authority, then the platform needs to expose more than product presentation. It needs to expose commercial truth. This is the second article in the Agent-Ready Commerce series. Part 1 introduced the broader model: Facts → Eligibility → Authority → State transition → Evidence → Audit This article focuses on the first part of that chain: facts . The central argument is simple: a raw product record is not enough for agent-ready commerce. The platform needs a source-backed, freshness-aware, action-supporting view of the product before agents can safely act on it. Product pages hide too much state A normal product page compresses many different concerns into one human-readable surface: Product identity Price Inventory Images Description Badges Variants Delivery estimate Return policy snippet Warranty information Promotional copy Reviews Cross-sell modules Checkout call to action That compression is useful for presentation, but it is lossy from a systems perspective. The page may show “In stock,” but the inventory value may be several hours old. It may show a price, but the pricing source may have changed since the last feed publication. It may show a return

A checkout saga spans inventory, payment, shipping, and loyalty. Downstream latency shifts every hour. Black Friday is not the day to discover your payment step timeout is baked into application.yml across twelve Spring Boot services. Kiponos.io gives every saga participant the same live orchestration parameters — step timeouts, retry budgets, compensation triggers — via one shared config tree. Each JVM reads locally on every saga step; ops adjusts once in the dashboard; WebSocket deltas propagate without redeploying the fleet. Why sagas break with static config Typical saga coordinator code: if ( step . elapsedMs () > 8000 ) { compensate ( "payment" , sagaId ); } That 8000 usually comes from: Per-service YAML — payment service says 8s, inventory says 12s; nobody agrees during an incident Env vars in Helm — change means rolling twelve deployments Shared DB config table — poll per step adds latency and coupling Saga steps are high-frequency reads inside workflow engines. You need local memory reads and async updates — the same contract as live API rate limits . Architecture: one tree, many participants ┌─────────────────┐ WebSocket deltas ┌──────────────────────┐ │ Kiponos.io UI │ ────────────────────────► │ Inventory service │ │ platform ops │ │ Payment service │ └─────────────────┘ │ Shipping service │ │ (each: in-mem SDK) │ └──────────┬───────────┘ │ .getInt() local ▼ ┌──────────────────────┐ │ saga step executor │ └──────────────────────┘ Every participant connects to profile ['orders']['v2']['prod']['sagas'] . When NOC extends payment.step_timeout_ms , all JVMs see the new value on the next step — no config server poll, no inter-service "what is timeout now?" REST calls. Shared saga config tree sagas/ checkout/ payment/ step_timeout_ms : 8000 max_retries : 2 retry_backoff_ms : 500 compensate_on_timeout : true inventory/ step_timeout_ms : 5000 max_retries : 3 hold_ttl_seconds : 120 shipping/ step_timeout_ms : 12000 fallback_carrier : ups_ground global/ saga_ttl_m

Operating system, a thing that everybody uses but no one talks about. While reading Operating Systems: Three Easy Pieces (OSTEP), my background in C and C++ fueled a growing fascination with memory allocation, virtualization, scheduling, and the intricate mechanics of operating systems. This would be a series of article, the number i am not sure, it will be the amount of content that someone might comfortably read in a 10 min Article. Keeping each piece to a solid 10-minute read is the perfect sweet spot for a developer to read over a cup of coffee. It gives you enough runway to explain a core concept, show the math, and link a practical C/C++ experiment without making their eyes glaze over. Why this Article ? We are often warned against “reinventing the wheel.” However, I firmly believe that building and optimizing modern software is impossible without a fundamental grasp of virtualization, memory allocation, and concurrency. Consider Docker: it functions almost entirely on OS-level virtualization features like Namespaces, cgroups, and isolated filesystems. Similarly, the highly optimized Memory Manager in PostgreSQL only works because it leverages the robust memory management systems already written into the OS kernel. This article aims to bring the core concepts of OSTEP to life through practical experimentation. By accompanying the theory with an open-source repository, my goal is to provide a clear, interactive learning experience that demystifies operating systems. I am not an operating system guru or a Principal Engineer with years of experience, but I hope to become one someday (assuming AI doesn’t replace me first… HeHe ). What I can do is dive in, explore, and try to understand these concepts by actually building things. Because of that, my goal here is to present the findings and experiments I explore rather than giving strong opinions — I’ll leave the comment section for those! Any support, feedback, or contributions from the community will be incredibly

Hello Devs, for months, I felt confident about system design interviews. I'd watched endless YouTube videos. I'd studied architecture diagrams. I could explain how Netflix builds recommendation systems. I understood Kafka, Redis, load balancers, and microservices. I'd memorized the designs of Twitter, Uber, YouTube, and TinyURL. Then I sat down for my first real system design interview and froze. The interviewer asked: "How would you design a notification system?" I had memorized notification systems. I knew about push notifications, email queues, delivery workers, and retry logic. I could recite architectural patterns. But suddenly, none of that helped. I didn't know which questions to ask first. I started designing before understanding the actual requirements. I built architecture for problems that didn't exist. I missed obvious bottlenecks. I couldn't articulate why I made specific trade-offs. When the interviewer pushed back, I had no framework to adjust. I failed that interview. But that failure taught me something crucial: System design interviews aren't about knowing technologies. They're about knowing how to think. After that, I went back and systematically practiced 20 system design problems. Not passively watching solutions. Actually designing. Making mistakes and refining my approach. And somewhere around problem 12, a pattern emerged. The best candidates didn't know more technologies than anyone else. They had a framework . They asked the same questions in the same order. They structured their thinking consistently. They could handle curveballs because their framework was flexible. They reasoned through trade-offs explicitly. Here's the framework that finally made it click for me. The Problem with Memorization Before I share the framework, let me explain why memorizing designs fails. When you memorize " How to Design Twitter," you learn: Use relational databases for users and tweets Use NoSQL for timelines Cache with Redis Use message queues for fanout S

Anthropic's engineers ship eight times more code than they did a few years ago. And they had to start scheduling lunches so people would talk to each other. Fiona Fung, who leads the Claude Code team, said it on Lenny's Podcast last week. Working with agents all day had started to feel isolating. The team was fast, but they'd stopped running into each other. So they added pairwise programming lunches and hackathons — rituals to put back the thing that used to happen on its own. Eight times the output. Scheduled conversation. That ratio is worth sitting with. Whatever goes missing here doesn't show up in the metrics. It doesn't throw an error. It just quietly stops being available. Here's the part that bugs me most. Ask an AI whether your approach is sound and it mostly tells you it is. Not because it's lying — because it's answering the prompt. No stake in the outcome, no history with the system, no memory of the last three times this exact idea was tried and quietly failed. A colleague pushing back is a different thing. They've got context you never typed into the window, because they were there when it was earned. They're going to maintain this too. They might be wrong — but wrong in a direction you hadn't thought of. An agent can't disagree with you like that. It agrees faster. Same with scope. The agent builds what you ask for, all of it, thoroughly. It won't mention that the third feature is the one nobody will use, or that "good enough" happened two iterations ago, or that something next door already solves most of this. Knowing when to stop comes from someone who's watched a codebase rot under a hundred individually-reasonable decisions. And it only knows what you put in front of it. The person who worked on payments remembers the edge case you're about to recreate. The junior who joined three months ago still sees the thing everyone stopped noticing. That gap — between what's in the window and what isn't — is where the expensive mistakes live. Then the part

I noticed something a few months ago. I was talking less to my colleagues. Not because anything was wrong. I had a question, I described it to an AI, I got something useful back. Why loop in a human if the loop is already closed? It took a while to name what was actually happening. There's a version of the AI story where the interesting work disappears. The agent implements. The spec session produces the plan. Humans review the output. What's left? Ticket hygiene and rubber stamping. Engineering as a series of approvals. I think that's wrong. But I understand why it feels true. Here's what I think is actually happening instead. The agent produces the increment. But the agent doesn't decide what the increment should move toward. It doesn't know whether this library is the right bet for the next three years. It doesn't know which of two implementation approaches leaves options open and which quietly closes them. It doesn't know whether the architectural call made today creates a problem nobody will notice until the system is under load eighteen months from now. That work — giving the project direction, validating trade-offs, deciding what the system becomes — isn't specable. You can't write a ticket for it. And it's not going away. The craft didn't disappear. It moved. Direction is the word I keep coming back to. The agent executes well. It implements against a spec. It generates options when you ask for them. But it doesn't carry a point of view about where the system should go. It doesn't have a stake in the decision. It will implement the wrong architectural direction just as confidently as the right one, if that's what the spec says. Someone has to hold the direction. Someone has to know enough about the codebase's history, the team's constraints, and the product's trajectory to say: not that library, we've been down that road. Not that pattern, it doesn't survive the load we're heading toward. This approach now, that refactor later, in this order, for these reaso

"A fool with a tool is still a fool." — often attributed to Grady Booch I keep coming back to this quote when I watch teams adopt AI. In my last post ( https://schrottner.at/2026/06/18/The-Wrong-End-of-the-Problem.html ) I wrote about shifting the engineering process left — spec sessions, autonomous agents, humans reviewing output rather than writing it. A few people asked the obvious follow-up: if an agent implements and an AI reviews, why do I need a team at all? It's a fair question. And I think the answer is in that quote. The agent validates against your prompt. That's it. If your thinking is muddled, the output will be muddled — just faster and at greater cost. An agent doesn't tell you that you're solving the wrong problem. It solves whatever problem you gave it, thoroughly and without complaint. Most AI usage right now treats AI as a tool. Which means the quality of the output is bounded by the quality of the thinking that went into the prompt. A fool with a tool is still a fool. The tool just makes the foolishness more expensive. The team is the check on intent. Not after the agent has burned three sprints on the wrong thing — before it starts. That's what mob planning actually is, when you think about it. Not a meeting. Not process overhead. It's the place where bad ideas get caught before they get expensive. Where someone asks "wait, why are we building this" before an agent runs with it for a week. But there's something else happening in that room that I think gets underestimated. It's where the learning happens. Not just prompting. System thinking. Architectural patterns. How to decompose a problem. Why a certain approach fits this codebase and another doesn't. How a senior frames a problem before an agent ever touches it — the mental model that makes the output actually good. Right now that knowledge isn't transferring. Everyone is heads-down with their own tools, developing their own habits in isolation. Engineer A gets dramatically better output than

Originally published at malaymehta.com The Interview Trap If you look at most system design tutorials, you get an extreme use case. Design Twitter. Design YouTube. Scale it to a billion users. Draw boxes on a whiteboard for 45 minutes. Do you think your app will be used by a billion users on day one? The answer is almost always no. But the tutorials don't teach you what to do when you have 500 users, unclear requirements, a team of four, and a quarter to ship something that works. Real system design is nothing like a whiteboard interview. You don't get clean requirements, you don't design from scratch, and nobody asks you to handle a billion requests per second on day one. Real System Design Starts with Questions, Not Diagrams The very first thing that matters in system design is something most tutorials skip entirely: unclear and chaotic requirements. In the real world, requirements don't come as a clean problem statement. They come from non-technical business teams, and you need to navigate through cross-questions to get all the clarity you need. Ask as many questions as possible. Understand your functional and non-functional requirements. Which features need to be synchronous and which can be async? What are the read and write load patterns? What is the maximum and average number of concurrent users right now? What does authentication look like? Do you need role-based access control? These questions drive your choices. You don't always need an axe where a knife will do. Being minimalist with a reasonable growth prediction and a 3, 6, 9 month plan will take you in the right direction. There will be things the situation demands immediately but would take more time than expected. Taking a predictable hit now and fixing it at the right future time without missing that balance is truly important. Weighing what will be expensive to change later, in terms of dollar cost or human effort, is how real architectural decisions get made. Pushing Back on Bad Requirements Many

Slack has outlined how its AI serving infrastructure evolved through four distinct phases, moving from a self-managed Amazon SageMaker deployment to a multi-cloud architecture spanning AWS Bedrock and Google Cloud Vertex AI. By Matt Foster

Backed by Mayfield and Aramco Ventures, Vishal Sikka’s new venture brings together veterans from SAP, Infosys, and VianAI.

Recently, we encountered a case on a RHEL 9 machine where an RPM query did not show any information about installed package even though the package files were present in the filesystem. Although RPM reported that the package was not installed, I was still able to run tcpdumpcommand and use it without any issues. The binary was present there in the filesystem and I was able to run it successfully. Fixing RPM Database Desynchronization on RHEL - bidhankhatri.com.np Recently, we encountered a case on a RHEL 9 machine where an RPM query did not show any information about installed package even though the package files were present in the filesystem. bidhankhatri.com.np

The safety board, known for its thorough investigations, is probing the crash alongside the National Highway Traffic Safety Administration.

When designing systems like Facebook, WhatsApp, Netflix, Amazon, or Instagram, one of the first questions a system designer asks is: Can a single server handle the traffic? How much storage will be needed? Do we need caching? How much RAM should our cache have? How many servers should we deploy? Before discussing databases, load balancers, microservices, or caching layers, we need a rough understanding of the scale. This is where Back-of-the-Envelope Calculations come into the picture. Why Do We Need Back-of-the-Envelope Calculations? Imagine you're asked to design Facebook. If you immediately start drawing: Load Balancer ↓ Application Servers ↓ Redis Cache ↓ Database without knowing the expected traffic, you're designing blindly. System design is fundamentally about making trade-offs. To make those trade-offs, we first need estimates. Back-of-the-envelope calculations help us answer: How much traffic will the system receive? How much data will be generated? How much cache memory is required? How many servers are needed? The numbers don't need to be perfect. They only need to be close enough to make architectural decisions. What Exactly Is a Back-of-the-Envelope Calculation? A quick estimation technique used to approximate: Traffic Storage Memory Server Capacity using rough assumptions. Think of it as: "Getting the order of magnitude correct rather than getting the exact number correct." A system designer rarely needs perfect accuracy during interviews. They need reasonable estimates. The Standard Estimation Flow Whenever you get a System Design question: Users ↓ Traffic ↓ Storage ↓ RAM / Cache ↓ Number of Servers ↓ Architecture Design Always estimate first. Design later. The Ultimate Estimation Cheat Sheet Storage Units Unit Value 1 KB 10³ Bytes 1 MB 10⁶ Bytes 1 GB 10⁹ Bytes 1 TB 10¹² Bytes 1 PB 10¹⁵ Bytes Time Units Unit Value 1 Minute 60 Seconds 1 Hour 3600 Seconds 1 Day 86,400 Seconds Common Assumptions Metric Approximation Peak Traffic 3× Average Traffic Active

Synchronous billing is easy, and that's the problem — it makes you think all billing is easy. When a request does its work inline, the billable number is in the response by the time you send it. The gateway meters from there — the meter write, retries and all, is its problem, not yours. From your side, synchronous billing is one number in the response. Asynchronous work breaks that. The request submits a job; the work happens later, in a worker; the result comes back through a poll or a callback. And the thing you bill for — characters processed, pages converted — isn't known when the request arrives. It's known when the job finishes . So you can't meter at the edge. The meter has to fire from the completion path. And the real difficulty is firing it exactly once per unit of completed work — because requests, polls, and retries all conspire to make that zero times or many times. This is platform-agnostic. Every submit-process-poll API has it. I'll use the system I run as the example, but the shape is the same anywhere. Three ways metering goes wrong On arrival. Carry the synchronous habit over and you meter when the job is submitted. But you don't know the size yet, so you're forced into a crude flat fee — or you bill for work that hasn't happened and might fail. Wrong unit, wrong time. On retrieval. The subtle one. You wire the meter to fire when the client fetches the result. Now a client who submits a job, lets it run — costing you real money downstream — and never bothers to poll is never billed. You did the work for free. "Completion" is not "the client picked up the result." It's the worker finishing. Without a fixed quantity. Input characters or output characters? Pages before OCR or after? If you haven't decided exactly what you measure and where, invoices drift and customers argue. Decide once; measure there. All three point the same way: meter on measured work-completion, with a fixed definition of the unit. Not on arrival. Not on retrieval. The mechanism:

Long-running workflows look simple when you first build them. Something happens. A few systems exchange data. Everything completes. Done. At least that's the expectation. Reality is very different. The biggest thing I underestimated was time. Not execution time. Elapsed time. Because once workflows start running for hours, days, or continuously, strange things start happening. APIs become temporarily unavailable Data changes halfway through the process Retries arrive much later than expected Someone manually updates a record Another system processes things in a different order Nothing is broken. But everything is slightly different from when the workflow started. Early on, I assumed workflows were transactions. Start. Execute. Finish. Now I think of them as conversations between systems. And conversations can get interrupted. Another thing I underestimated: State changes. You might start processing an order that is "pending". Ten minutes later, another system marks it as "cancelled". An hour later, a retry comes in from an earlier step. If your workflow only thinks about data, weird things happen. Because the world has changed while the process was still running. Long-running workflows also expose assumptions you didn't know you made. Like: this API will always respond quickly data will arrive in order users won't modify records manually retries will happen immediately Those assumptions survive in testing. Production removes them quickly. One thing that changed how I build these systems: I stopped asking: "Will this workflow finish?" And started asking: "What state will the world be in when it finishes?" Because those are two very different questions. Most problems in long-running systems aren't caused by one big failure. They're caused by lots of small changes happening while the workflow is still alive. And if you don't account for that, eventually the workflow finishes successfully and still produces the wrong outcome. This is something we think about constantly