标签：#architecture

Azure Functions shipped a serverless agents runtime in public preview at Build 2026. Agents are defined in .agent.md markdown files with YAML triggers, MCP server access, 1,400+ connectors, and sandboxed execution. The Functions team confirmed to InfoQ that the runtime adds no cold start overhead and no billing premium beyond standard Flex Consumption. By Steef-Jan Wiggers

Your repo is already your agents' context, whether you designed it on purpose or not That sentence took me a while to understand. In this post I'll save you the trip. It was October 2025, working in Skyward's monorepo with AI agents every day. And every day the same routine: I'd tell the agent in the prompt "don't use this", "don't do it this way", "reuse the component that already exists". I wrote it down. I repeated it. The agent did exactly what I told it not to do. It wasn't that it didn't listen to me. It was that it read the code and saw something else there. The agent believes the code, not your prompt An agent follows the patterns it sees in the repo, not the ones you tell it in the prompt. And subagents are worse, because they start without the conversation's context. The whole fight you put up earlier in the chat, for them it never happened. So this is what kept happening. It created a new component even though one already existed that solved exactly that problem. It didn't respect the design rules or use the design tokens. It followed stale docs because they were still there, alive, with nothing flagging them as outdated. My first instinct was everyone's instinct, cram more context into the prompt. More rules, more "please don't do this", more examples pasted in by hand. It half worked, and for the next task you had to add it all again. Until the next subagent showed up and started from scratch. At some point, tired of repeating myself, I understood the obvious thing. The agent wasn't disobeying me. It was reading the repo and listening to what the repo said about itself. If the good component lives alongside three old versions, it has no way to know which one is the official one. If the docs say one thing and the code does another, it'll believe whichever is closest at hand. It's doing exactly what I asked. The repo itself is the context agents use. If it's badly structured, the answers won't be good. Period. No prompt fixes a repo that contradicts itsel

Tu repo ya es el contexto de tus agentes, lo hayas diseñado a propósito o no Esa frase me costó entenderla. En este post te ahorro el camino. Era Octubre del 2025, trabajando en el monorepo de Skyward con agentes de IA todos los días. Y todos los días la misma rutina: le decía en el prompt al agente "no uses esto", "no hagas esto así", "reutiliza el componente que ya existe". Lo escribía. Lo repetía. El agente hacía exactamente lo que le dije que no hiciera. No era que no me escuchara. Era que leía el código y ahí veía otra cosa. El agente le cree al código, no a tu prompt Un agente sigue los patrones que ve en el repo, no los que tú le dices en el prompt. Y los subagentes son peores, porque arrancan sin el contexto de la conversación. Toda la pelea que tú diste arriba en el chat, para ellos no existió nunca. Entonces pasaba esto. Creaba un componente nuevo aunque ya había uno que resolvía exactamente el problema. No respetaba las normas de diseño ni usaba los design tokens. Seguía documentación obsoleta porque seguía ahí, viva, sin nada que la marcara como obsoleta. Mi primer instinto fue el de todos, meter más contexto en el prompt. Más reglas, más "por favor no hagas esto", más ejemplos pegados a mano. Funcionaba a medias, y para la siguiente tarea había que volver a agregarlo todo. Hasta que llegaba el siguiente subagente y empezaba de cero. En algún momento, cansado de repetirme, entendí lo obvio. El agente no me estaba desobedeciendo. Estaba leyendo el repo y haciendo caso a lo que el repo decía de sí mismo. Si conviven el componente bueno y tres versiones viejas, no tiene cómo saber cuál es el oficial. Si la doc dice una cosa y el código hace otra, le va a creer al que esté más a mano. Está haciendo justo lo que le pedí. El mismo repo es el contexto que usan los agentes. Si está mal estructurado, las respuestas no van a ser buenas. Punto. No hay prompt que arregle un repo que se contradice a sí mismo. Screaming Architecture me llevó hasta media cancha Lo prim

Architecture Overview Clioloop's Agentic Fusion is not just "run the same prompt 5 times and pick the best." It's a structured pipeline where different models play different roles, with strict security boundaries between them. The Pipeline Step 1: Planning Phase When you run /fusion , up to 5 planner models are dispatched in parallel. Each planner: Receives your original prompt and context Has read-only tool access — they can search the web, read files, but never modify anything Proposes an approach (not an answer — an approach) The planners might suggest different strategies: Planner A: "Search the web for similar problems, then write a script" Planner B: "Read the existing codebase first, then modify in place" Planner C: "Break it into subtasks and use the Kanban system" Step 2: Execution Phase Your main model takes the planners' proposals and does the actual work: Full tool access (file editing, shell, web, browser, image gen, etc.) Fully visible — you watch every file edit, every command, every web search in real time Not a black box — you can intervene at any time This is the key difference from "ensemble" approaches: the main model does real work with real tools, not just text generation. Step 3: Review Phase Up to 5 reviewer models critique the draft: Read-only access — they can see what the main model produced, including generated images They check for errors, suggest improvements, flag problems Each reviewer works independently Step 4: Verdict Loop The draft is revised based on reviewer feedback: If reviewers find issues, the main model gets the feedback and revises The loop continues until reviewers approve You get the final, reviewed answer Step 5: Fusion Everything combines into one answer that has already passed independent review. Security Model The safety comes from schema-level restrictions : Role Can Read Can Write Can Execute Planners ✅ Files, web, images ❌ Nothing ❌ Nothing Main Model ✅ Everything ✅ Files ✅ Commands Reviewers ✅ Draft, files, image

Building a high-performance Polymarket trading bot requires mastering its unique hybrid architecture:...

Vinay Chella and Akshat Goel discuss the challenges of running traditional CDC across heterogeneous databases during peak order traffic. They explain how Debezium hit limits under high load and share how they built Write-Ahead Intent Log (WAIL) - a custom architecture that utilizes a dumb producer proxy and a smart consumer pattern to cleanly separate the intent from the state payload. By Vinay Chella, Akshat Goel

Ok so first, let me be honest. This post is partly me venting. I've been maintaining node-dependency-injection for about 9 years now. 300 stars on GitHub. Not exactly viral. And every time I look at InversifyJS or tsyringe climbing in popularity I think "yeah, but at what cost". So let me explain my problem with decorators. The coupling nobody talks about When you write this: @ Injectable () export class UserService { constructor (@ Inject ( MAILER_TOKEN ) private mailer : IMailer ) {} } Where does that @Injectable() live? In your DI framework. Which means your UserService — which is domain logic, business rules, the thing that should outlive any framework decision — now has a direct dependency on your IoC container library. Your domain knows about your infrastructure. That's the wrong direction. I know, I know. "It's just a decorator, it doesn't do anything". But it's still an import. It's still coupling. And if you ever want to swap the container, or move that service somewhere else, or just test it without spinning up the whole container — you now have to think about it. With NDI, your service is just a class: export class UserService { constructor ( private mailer : IMailer ) {} } That's it. No imports from my library. No decorators. No metadata. The service doesn't know it's being injected. The wiring lives completely outside — in a YAML file or in a bootstrap file. Your domain stays clean. "But Symfony does decorators and it's fine" Symfony doesn't use decorators in services actually. The DI config is external — YAML, XML, PHP config files. Your service is just a PHP class. That's literally what inspired NDI from the beginning. What NDI actually does Quick example. You have two payment providers and you want to inject the right one based on context: services : payment.stripe : class : ' payments/StripePayment' keyed : group : payment key : stripe default : true payment.paypal : class : ' payments/PaypalPayment' keyed : group : payment key : paypal checkout.ser

One of the oldest axioms of software engineering is that code is written primarily for humans to read, and only secondarily for machines to execute. Clean code, expressive variable names, and architectural elegance all serve a single purpose: to ensure that the next developer - or our six-months-older self - can understand what on earth happened. Code has always been a cultural artifact, a shared language, a bridge between human intent and silicon. But what happens to this bridge in the era of vibe coding? We are rapidly moving toward a reality where code is generated by LLMs and pull requests are reviewed by LLMs. When the resulting string of characters is spawned by a machine and audited by a machine, human readability immediately ceases to be a primary metric of quality. This forces a radical question upon us: If code no longer needs to be human, does the code itself need to change? Why do we still cling to Python, to micro-frontends, or to neatly structured repositories? We invented these structures to accommodate the cognitive limitations of the human brain - to keep ourselves from drowning in complexity. An AI doesn’t need these training wheels. To an LLM, a 50,000-line monolithic spaghetti-code mess, completely impenetrable to a human eye, is just as easy to parse as the most pristine clean architecture. So, what is the point of the code itself? Is it possible that code is merely a transitional, obsolete interface—a form of "digital carbon monoxide" that we will soon phase out entirely, replacing it with pure intent and mathematical weights? I ran this exact thought experiment in practice recently when I built a tiny, native macOS utility called Portia over a single weekend (you can check it out here: getportia.app ). The app's function is dead simple: when a port gets stuck (EADDRINUSE), it frees it up with a single click. Throughout development, I was almost exclusively in vibe coding mode. I wasn’t thinking about syntax; I was thinking about the problem an

How we decide is at the core of architecture, and the architecture advice process is a way to decentralize architectural decisions. It needs to be supported by Architecture Decision Records because of the speed at which technology and systems move, and can be complemented by a weekly architecture advice forum. By Ben Linders

VS Code 1.123 adds a two-hour delay before auto-updating extensions to newly published versions, creating a revocation window against supply chain attacks. The delay does not apply to trusted publishers like Microsoft, GitHub, and OpenAI. Similar cooldown mechanisms have now spread across pip, RubyGems, npm, pnpm, Yarn, and Bun. By Steef-Jan Wiggers

One of the most common system design interview questions is: "How would you scale a web application from 100 users to 100 million users?" The answer is rarely a single technology. Instead, systems evolve through multiple stages, with each stage solving a specific bottleneck. This article walks through the typical evolution of a scalable system and explains why , how , and when each component is introduced. 1. Single Server Why Start Here? Every application starts simple. In the beginning: Traffic is low Development speed matters more than scalability Infrastructure costs should be minimal What Is It? A single machine handles everything: Frontend Backend Database Users | v Single Server ├── Application └── Database How Does It Work? User sends request. Application processes request. Database stores and retrieves data. Response is returned. Everything happens on one machine. Problem As traffic grows: CPU becomes overloaded Memory becomes insufficient Database competes with application for resources A single server becomes a bottleneck. Interview One-Liner A single server architecture is simple and cost-effective but becomes a bottleneck as traffic and resource usage increase. 2. Application and Database Separation Why Do We Need It? The application and database have different workloads. Application Server: Uses CPU Handles business logic Database Server: Uses memory and storage Handles queries Keeping them together causes resource contention. How Does It Work? Move the database to a separate machine. Users | v Application Server | v Database Server Benefits Independent scaling Better resource utilization Improved performance Example Suppose an e-commerce website receives thousands of requests. The application handles: Authentication Order processing API responses The database handles: Product data Orders User information Separating them prevents one workload from affecting the other. Interview One-Liner Separating the application and database allows each layer to scal

Originally published on lavkesh.com I recall one of the first design decisions for our payments platform, which was to deploy an in-memory cache for low-latency access to customer account balances. The architecture diagrams looked clean, with Go services using sync.Once-initialized maps in memory, bypassing the database for sub-millisecond reads. However, this approach worked as expected for only three months, until users started reporting inconsistent charges on receipts. The problem surfaced at peak hours when concurrent updates to the same balance would overwrite each other. For instance, the account balance for user ID 12345 went from $1,200 to $850 to $1,200 again within seconds, leaving the cache in a state that defied the database of record. Engineers stared at the logs, baffled by the mismatch between transactions and cached values, because the team had not accounted for the fact that memory maps are not thread-safe by default in Go. Debugging revealed the fundamental error: we were optimizing for speed without considering write-through guarantees. The cache treated concurrent requests as idempotent, which they were not. During a single user’s purchase flow, multiple goroutines could validate the balance, each reading a stale value from memory before any had a chance to commit updates. We had to shift to Redis with explicit lock keys and time-to-live settings, adding 4 milliseconds of latency but ensuring atomicity. The cache also invalidated itself only when a change occurred, not when an upstream source updated. We discovered this when the accounting team reconciled overnight and adjusted balances based on fee settlements - the cache never reflected these updates until it expired naturally. To fix this, we had to implement message queues to broadcast invalidation events across all services. What started as a performance optimization became three nights’ worth of rewriting concurrency models. This experience taught me two concrete lessons about distributed

When organizations scale, a simple monolithic architecture often becomes difficult to maintain, deploy, and scale. This is where microservices come into the picture. However, moving to microservices introduces new challenges: How do we migrate from a monolith safely? How do we handle transactions across multiple services? How do we scale read-heavy applications efficiently? Three popular patterns solve these problems: Strangler Pattern – Monolith to Microservices Migration Saga Pattern – Distributed Transaction Management CQRS (Command Query Responsibility Segregation) – Read/Write Scalability 1. Strangler Pattern Why Do We Need It? Most companies cannot shut down a production monolith and rewrite everything from scratch. A complete rewrite is risky because: Development takes a long time. Existing customers are affected. Bugs can impact business operations. Rollback becomes difficult. The Strangler Pattern allows teams to migrate gradually with minimal risk. What Is It? The Strangler Pattern is a migration strategy where new microservices slowly replace parts of a monolithic application until the monolith is no longer needed. The name comes from the strangler fig tree, which gradually grows around another tree and eventually replaces it. How Does It Work? [Insert diagram here showing Client → API Gateway → Monolith + Microservices] Step 1 All requests go to the monolith. Client | v Monolith Step 2 Introduce an API Gateway (or Controller). Client | v API Gateway | v Monolith Step 3 Extract one module into a microservice. Client | v API Gateway |------> Order Service | v Monolith Step 4 Gradually move more modules. Client | v API Gateway |------> Order Service |------> Payment Service |------> Inventory Service | v Monolith Step 5 Eventually remove the monolith completely. Example Consider an e-commerce application. Initially, everything exists inside one application: Monolith ├── Orders ├── Payments ├── Inventory └── Users Over time: Orders become Order Service Payme

Amazon Fulfillment: The Three Tiers of Optimization Amazon processes billions of orders annually through a network of over 175 fulfillment centers globally. To maintain their 1-2 day (or same-day) delivery guarantees, they built a 3-tier optimization architecture: ┌─────────────────────────────────────────────────────────────┐ │ TIER 1: ANTICIPATORY SHIPPING (Long-term — weeks/months) │ │ → ML predicts demand → Moves inventory close to customers │ │ BEFORE they place an order │ ├─────────────────────────────────────────────────────────────┤ │ TIER 2: REGIONALIZATION (Medium-term — days/weeks) │ │ → Partitions the fulfillment network into autonomous zones│ │ → Ensures 70-80% of orders are fulfilled intra-region │ ├─────────────────────────────────────────────────────────────┤ │ TIER 3: CONDOR (Short-term — hours) │ │ → Continuously re-optimizes the fulfillment plan within │ │ a 5-6 hour window before pick-and-pack begins. │ └─────────────────────────────────────────────────────────────┘ Anticipatory Shipping — Shipping Before You Buy A Crazy but Effective Idea Amazon holds a patent (US Patent 8,615,473) describing a system that begins shipping items BEFORE a customer places an order . It sounds like science fiction, but it's a reality. Traditional Model: Customer orders → Warehouse processes → Ships → Delivered (2-5 days) Anticipatory Shipping: ML predicts: "Customers in Region X will buy 200 iPhone 16s in the next 3 days" → Amazon ships 200 iPhones from a central hub to local delivery hubs in Region X → Customer places order → The item is already locally staged → Delivered same-day! ML Model Input Features Input Feature Significance Purchase history What do they buy, and how often? Browsing behavior What are they looking at? Cart abandonment? Wishlists Explicitly desired items Seasonal patterns Winter coats in November, sunscreen in June Regional demographics High-income areas? Young families? College towns? Trending products Items going viral on social media Weathe

Abstract In modern software engineering, writing code that simply "works" is only the first step. The real challenge lies in designing systems that are maintainable, scalable, and easy to test. This article explores the Dependency Inversion Principle (DIP), the final pillar of the SOLID design principles. Through a practical, real-world example in Kotlin, we will demonstrate how to transition from a tightly coupled architecture to an abstraction-based design. This shift dramatically improves our codebase, facilitates unit testing, and prepares our applications for future growth. Introduction: The Chaos of Coupling As applications grow, it is common to see how a minor change in a database schema or a third-party API triggers a domino effect, breaking unrelated parts of the system. This fragility is a direct consequence of tight coupling. Software design principles, particularly SOLID, were established to prevent this architectural decay. Today, we focus on the "D" in SOLID: the Dependency Inversion Principle (DIP). This principle establishes two core rules: High-level modules should not depend on low-level modules. Both should depend on abstractions (interfaces). Abstractions should not depend on details. Details (concrete implementations) should depend on abstractions. The Scenario: An E-commerce Payment Processor Imagine you are building the billing system for an online store. To process purchases, the system needs to connect to a payment gateway, such as PayPal. The Bad Way: Tight Coupling (Violating DIP) In this initial design, our high-level business logic (OrderProcessor) directly instantiates and depends on the concrete low-level class (PayPalService). // Low-level component (Concrete detail) class PayPalService { fun executePayment(amount: Double) { println("Processing payment of $$amount via PayPal API.") } } // High-level component (Business logic) class OrderProcessor { // Tight coupling: this class depends directly on a concrete implementation private val

I promised myself that starting this week I'd switch to lighter topics. But on Monday, my JSNation...

Every non-trivial business operation touches more than one system. An e-commerce order reserves inventory, charges a payment method, and schedules a shipment — three services, three databases. A bank transfer debits one account and credits another across two ledgers that may not even be in the same data center. A cloud VM provisioning workflow reserves a network port, allocates storage, starts the hypervisor, registers billing, and sends a notification — five services, five independent state stores. The question is: what happens when step four fails after steps one through three have already succeeded? In a monolith backed by a single database, the answer is simple: roll back the transaction. The database engine guarantees atomicity; either everything commits or nothing does. But when your workflow spans multiple services, each owning its own storage, there is no transaction boundary that wraps them all. There is no rollback button. Step one through three have already made durable changes to systems that do not know about each other, and step four's failure has left the system in an inconsistent state. This is not a pathological edge case. It is the default condition in any distributed architecture. And it gets worse: the failure might not be a hard error. The network might time out. The billing service might return a 503. You do not know whether step four applied its effect or not — you only know you did not receive a success response. Now what? This is the problem sagas were designed for. Client Inventory Svc Payment Svc Shipping Svc │ │ │ │ 1 │──reserve(item)──►│ │ │ │◄──── 200 OK ─────│ │ │ │ [reserved ✓] │ │ │ │ │ │ 2 │──────────── charge(card, $99) ────►│ │ │◄───────────────── 200 OK ──────────│ │ │ │ [charged ✓] │ │ │ │ │ 3 │─────────────────────── schedule(order) ─────────────►│ │◄─────────────────────────── 503 ──────────────────── │ │ │ │ [no record ✗] │ │ │ │ ╔══════════════════════════════════════════════════════╗ ║ ⚠ Inconsistent state ║ ║ Inventory: it

A common way to design an application is to begin with its nouns: User Product Order Payment Then each noun receives the standard architectural starter pack: UserController UserService UserRepository The controller receives users, the service services them, and the repository stores them somewhere responsible. This is noun-oriented architecture : treating every important thing in the domain as if it were automatically a useful software boundary. It works for simple CRUD systems. Unfortunately, most applications eventually do something. The noun becomes a drawer Consider a typical UserService : register() findByEmail() resetPassword() changeAddress() disableAccount() mergeAccounts() assignRole() calculateDiscount() These operations all involve a user. That is approximately where their similarity ends. They have different rules, dependencies, side effects, security concerns, owners, and reasons to change. They live together because User was the nearest available noun when the folders were created. As more behaviour accumulates, UserService becomes the official location for anything vaguely user-shaped. Other components depend on it. It gradually depends on authentication, email, permissions, billing, auditing, and several services added during incidents nobody wishes to revisit. The noun becomes both a dependency of everything and a consumer of everything. The folder remains impressively tidy. Name the capability, not the material A better starting question is not: What things exist in this system? It is: What must this system be capable of doing? That leads to components such as: UserRegistrar PasswordResetter AccountMerger OrderPlacer PaymentRefunder SubscriptionCanceller These are agentive names . They name the component responsible for performing a capability. Compare: UserService with: PasswordResetter UserService tells us which noun is nearby. PasswordResetter tells us what the component is for. That difference produces better architectural questions: What rules

Rate Limiting and Circuit Breakers in Distributed AI Systems Distributed AI systems are inherently complex, handling massive volumes of requests, variable latency from model inference, and dependencies on external services like GPU clusters, databases, or third-party APIs. Without proper safeguards, a single misbehaving component or a sudden traffic surge can cascade into system-wide failure. Two fundamental patterns— rate limiting and circuit breakers —provide essential protection. This post explores their roles, implementation strategies, and practical Python examples tailored for AI workloads. Why Distributed AI Systems Need These Patterns Consider a typical AI pipeline: a user sends a prompt, which hits a load balancer, then an API gateway, then an inference service (e.g., a large language model), which may call a vector database or a fine-tuning API. Each component has capacity limits: GPU inference servers can handle limited concurrent requests. External APIs (e.g., OpenAI, HuggingFace) impose rate limits. Database connections are finite. Without rate limiting, a single abusive client can exhaust resources. Without circuit breakers, a failing downstream service can cause cascading timeouts and resource exhaustion across the entire system. Rate Limiting: Controlling Request Flow Rate limiting restricts how many requests a client, user, or service can make in a given time window. It prevents resource starvation and ensures fair access. Common Algorithms Algorithm Pros Cons Token Bucket Smooth burst handling, easy to implement Memory per bucket Leaky Bucket Constant outflow rate, simple Less flexible for bursts Fixed Window Simple, low overhead Boundary spikes (reset issues) Sliding Window Smoother than fixed, accurate Slightly more complex For AI systems, token bucket is often preferred because it allows short bursts (e.g., a user sending a batch of prompts) while maintaining a long-term average. Python Implementation: Token Bucket Rate Limiter import time impor

Your backend returned 200. The mobile app showed an error. The user tapped "Pay" three times. Three pending charges hit their account. One order was placed. Their balance was short. And your incident log showed zero failures. Every engineer on the team did their job. Nobody solved the problem. This is the most common way engineering teams fail, not through incompetence, but through excellent execution of the wrong unit of work. And until you recognise the difference between completing a task and solving a business problem , you will keep shipping systems that work perfectly and experiences that don't. The Ticket-Thinker vs. The System-Owner Most engineers early in their careers think in tickets. Ticket assigned → code written → tests pass → PR merged → ticket closed. Done. This is fine when you're learning. It's a liability when you're trying to grow. The engineer who closes tickets is useful. The engineer who asks "what problem does this ticket actually solve, and am I solving it in the right place?" that engineer is dangerous in the best way. Here's the distinction in practice. The backend engineer builds a payment endpoint. It processes charges correctly, returns the right status codes, has proper error handling. 100% test coverage. Ticket closed. The mobile engineer builds the payment screen. It calls the endpoint, handles the response, shows confirmation or error. Smooth UI. Ticket closed. The problem nobody owned: what happens when the network drops after the backend processes the charge but before the mobile app receives the confirmation? The backend: charge processed. No error. The mobile: timeout. Shows "Payment failed." User retries. The user: charged twice. Both engineers solved their assigned problem correctly. The business problem — charge the user once and confirm it reliably — went unsolved. Because that problem lived in the space between their tickets, and nobody was watching that space. Real Scenario 1: The Payment That Worked and Failed at the Same