标签：#architecture

Introduction Large Language Models (LLMs) like ChatGPT have transformed how we interact with AI. They can write code, answer questions, summarize documents, and generate creative content. However, they have one major limitation - they only know what they were trained on and can sometimes generate incorrect or outdated information. So, how do modern AI applications answer questions about your company's private documents, recent news, or knowledge that wasn't part of the model's training? The answer is Retrieval-Augmented Generation (RAG). In this blog, we'll explore what RAG is, how it works, its architecture, benefits, challenges, and real-world applications. What is RAG? Retrieval-Augmented Generation (RAG) is an AI architecture that combines a retrieval system with a Large Language Model (LLM). Instead of relying only on the model's internal knowledge, RAG first retrieves relevant information from an external knowledge source and then uses that information to generate a more accurate response. Think of it like an open-book exam. Instead of answering from memory, the AI first searches for the most relevant pages and then writes the answer based on those pages. Why Do We Need RAG? Traditional LLMs have several limitations: Knowledge becomes outdated. They cannot access private company data. They may hallucinate (generate incorrect facts). Retraining models is expensive and time-consuming. RAG solves these problems by allowing the model to retrieve fresh and domain-specific information before generating an answer. RAG Architecture A typical RAG pipeline consists of the following components: User Query Embedding Model Vector Database Retriever Prompt Builder Large Language Model Final Response Step-by-Step Workflow * Step 1: * User asks a question Example: "What is our company's leave policy?" Step 2: Convert the question into embeddings The query is transformed into a vector representation using an embedding model. Example: "What is leave policy?" ↓ [0.12, -0.45, 0.7

Architecture that lives only in people's heads doesn't survive agents. For most of my career, the real rules of a codebase weren't written down. People knew them. Senior engineers knew which layers could talk to which. They knew which dependencies were forbidden, which schemas were effectively frozen, and which shortcuts would create problems six months later. New engineers learned those rules the traditional way: break one, get caught in review, get the explanation, and eventually remember not to do it again. It wasn't perfect, but it mostly worked. What I didn't fully appreciate until I started working heavily with coding agents is how dependent that model is on tribal knowledge. Humans accumulate context over time. Agents don't. They don't remember the migration that went sideways three years ago. They weren't around when the team spent weeks untangling a dependency cycle. They don't know why a particular boundary exists. They only know what they can see. Which means if a rule isn't written down, from the agent's perspective, the rule doesn't exist. I've seen agents wire inner layers directly to outer layers. I've seen them introduce dependencies we intentionally avoided and extend contracts everyone on the team considered settled. The code often worked, which was the dangerous part. The problem wasn't correctness. The problem was architectural drift. That's when something clicked for me. Architecture can't remain folklore once agents start writing code. It has to become law. Not a convention. Not a suggestion. Not something a reviewer remembers at 6 PM on a Friday. A law. Written down, explicit, and enforceable. That's what I mean by a constitution. A Constitution Is Not Documentation The first mistake I made was treating the constitution like another documentation file. It isn't. Documentation explains how the system works today. A constitution defines what the system is allowed to become. Those sound similar, but they serve very different purposes. Package nam

Using Claude Fable 5 or Mythos 5 on Amazon Bedrock requires opting into provider_data_share, sending prompts and outputs to Anthropic for 30-day retention with human review. Previous Bedrock models kept inference data inside the AWS boundary. Three days after launch, Anthropic asked AWS to revoke access to both models citing US export control compliance. By Steef-Jan Wiggers

Enterprise Design Patterns in Python: Repository & Unit of Work 🐍🏗️ Series: Enterprise Application Architecture | Source: Fowler's EAA Catalog | Code: GitHub Repository 🧠 What Are Enterprise Design Patterns? Martin Fowler's Patterns of Enterprise Application Architecture (2002) is one of the most influential books in software engineering. It documents recurring architectural solutions — patterns — that solve common problems in enterprise systems: how to organize domain logic, how to talk to databases, how to handle transactions, and more. In this article, we'll explore two of the most powerful and widely-used patterns from that catalog: Pattern Category Core Purpose Repository Data Source Abstracts data access behind a collection-like interface Unit of Work Data Source Tracks object changes and commits them as a single transaction These two patterns work beautifully together — and you'll see exactly why with a real-world example. 🛒 The Problem: An E-Commerce Order System Imagine you're building a backend for an online store. When a customer places an order: A new Order is created Each Product 's stock is decremented A Payment record is registered If any of these steps fail midway, the entire operation should roll back — no partial state. This is exactly the problem the Unit of Work pattern solves, and the Repository pattern makes it all cleanly testable. 📁 Repository Pattern Definition "A Repository mediates between the domain and data mapping layers using a collection-like interface for accessing domain objects." — Martin Fowler, PoEAA The Repository acts as an in-memory collection of domain objects. Your business logic never knows if it's talking to PostgreSQL, SQLite, or even a mock list — it just calls .add() , .get() , .list() . Domain Model # models.py from dataclasses import dataclass , field from typing import List from uuid import uuid4 @dataclass class Product : id : str name : str price : float stock : int @dataclass class OrderItem : product_id : str qua

A finance bot kept issuing refunds in a loop because nobody built a way to stop it. Clean code. Sound logic. No off switch. A small bug became a long night. Here is the opinion most teams do not want to hear. Building the agent is the easy 80 percent. That off switch is the 20 percent that decides whether you can ship it at all. We celebrate the wrong milestone. Picture the demo where the agent books the meeting, writes the email, updates the record. That part is genuinely fun to build and genuinely easy now. Harder is the boring question nobody claps for. What happens when it is wrong, fast, and confident. An AI agent is not a chatbot. It takes actions in the real world. It spends money, deletes rows, messages real people, moves files. Wrong answers in a chat are annoying. A wrong action at machine speed is an incident with your name on it. So before features, I build the stop. One real kill switch is not a single button. Think of it as a small set of bounds that live from the first version. A spend ceiling, so a retry loop cannot drain the account A blast radius limit, so one task can never touch more than it should A human gate on anything irreversible, so the agent proposes and a person commits A global stop that halts everything in one move, with no redeploy None of that is glamorous. All of it is what lets you sleep at night. Teams skip this for a reason that feels rational in the moment. Bounds feel like negative work. They never show up in the demo. Your agent runs fine without them right up until the one time it does not, and that one time is the only time anyone remembers. Here is the reframe that changed how I build. Treat the stop as the feature that makes an agent shippable. Bolt it on at the end and you have already shipped a liability that happens to pass the demo. Honest about the trade-off. Bounds slow you down. You will watch the agent pause for an approval it could technically have skipped, and it will feel like friction. That friction is the pric

Durante mucho tiempo asocié el desarrollo de software con programar funcionalidades: crear entidades, armar controladores, conectar una base de datos, validar formularios y hacer que una aplicación responda correctamente. Sin embargo, durante el Trabajo Final de la asignatura Desarrollo de Aplicaciones Web , entendí que programar es solo una parte del problema. El verdadero desafío aparece antes de escribir código: decidir qué arquitectura conviene, por qué conviene, cuánto cuesta, qué riesgos resuelve y qué complejidad agrega. El trabajo consistió en diseñar un sistema de gestión clínica que comenzaba como un MVP para una única clínica y evolucionaba progresivamente hacia una plataforma SaaS multi-tenant . Aunque fue un proyecto académico, el ejercicio nos obligó a pensar como si estuviéramos tomando decisiones técnicas en un contexto real: con restricciones de negocio, costos, equipo, seguridad, datos sensibles y crecimiento futuro. La principal enseñanza fue: la mejor arquitectura es la que responde mejor al momento del producto . El primer desafío: no sobrediseñar desde el inicio Cuando empezamos a pensar el sistema, la tentación era ir directamente a una arquitectura compleja: microservicios, eventos, colas, Kubernetes, múltiples bases de datos y despliegues independientes. Pero al analizar el escenario inicial, esa decisión no tenía sentido. El sistema comenzaba para una sola clínica, con un presupuesto reducido y con requisitos todavía en etapa de validación. En ese contexto, arrancar con microservicios hubiera agregado más problemas que beneficios: comunicación entre servicios, contratos, versionado, observabilidad distribuida, debugging más difícil y mayor costo de infraestructura. Por eso, una de las decisiones más importantes fue comenzar con una arquitectura en capas , desplegada como un único proceso. Esta elección permitió separar responsabilidades sin asumir desde el principio la complejidad de un sistema distribuido. La capa de presentación se encarg

As developers, we’ve all been there: you’re building a hobby project, a side hustle, or a microservice, and you need object storage. You look at AWS S3 or dedicated cloud providers, and the costs start adding up. Meanwhile, most of us have hundreds of gigabytes of idle, wasted space sitting in our personal Google Drive, Dropbox, or Mega accounts. I wanted to find a way to use that personal cloud storage programmatically—specifically as an S3-compatible bucket—without paying premium storage fees. But I had one strict rule for myself: The solution had to be 100% stateless. No caching files on my servers, no data retention, and zero storage costs on my end. Security and privacy meant that files had to exist on my infrastructure only in-flight as streaming data packets. Here is a deep technical breakdown of the architecture I built to make this happen using NestJS, Fastify, OpenDAL, and BullMQ in a monorepo structure. 1. The Core Architecture: A Monorepo Approach To keep performance blazing fast and maintain a clean separation of concerns, I broke the system down into three distinct, decoupled services inside a monorepo, sharing underlying core modules. Because raw Node.js HTTP overhead can become a bottleneck when proxying heavy streams, I swapped out Express for Fastify as the underlying HTTP provider for NestJS. ┌────────────────────────────────────────┐ │ Main API Server │ │ (Handles Auth, Web Dashboard, OAuth) │ └───────────────────┬────────────────────┘ │ │ (Pushes Sync/Heavy Tasks) ▼ ┌───────────┐ │ BullMQ │ └─────┬─────┘ │ ▼ ┌────────────────────────────────────────┐ │ Worker Server │ │ (Processes Heavy Background Jobs) │ └────────────────────────────────────────┘ ───────────────────────────────────────────────────────────────────────── ┌────────────────────────────────────────┐ │ S3-Compatibility Server │ │ (Streams Data / Translates S3 XML) │ └────────────────────────────────────────┘ The Main API Server: Handles user authentication, the web dashboard manageme

Single-model systems are simple. Multi-model systems are powerful. The challenge isn't choosing models — it's designing the architecture that orchestrates them. A multi-model system isn't about having more models. It's about having the right model for the right task at the right time. Architecture patterns Five patterns cover most use cases: Pattern Complexity When to use Tradeoff Single Model Lowest Prototyping, simple tasks Limited capability Sequential Low Multi-step workflows Higher latency Parallel Medium Independent tasks Higher cost Hierarchical High Complex reasoning Complex orchestration Ensemble Highest Critical decisions Highest cost Pick the simplest one that works. Complexity is real, and it compounds. Sequential architecture Process tasks through a chain of models, each specializing in a step. Pattern 1: Pipeline Pipeline pattern — each model's output feeds the next: class ModelPipeline : def __init__ ( self ): self . models = [ { " model " : " qwen2.5-1.5b " , " task " : " classify " }, { " model " : " qwen2.5-7b " , " task " : " extract " }, { " model " : " qwen2.5-32b " , " task " : " reason " }, ] def process ( self , input : str ) -> str : current = input for model_config in self . models : current = self . call_model ( model_config [ " model " ], self . create_prompt ( model_config [ " task " ], current ) ) return current Latency adds up. Three models in sequence means three times the latency. Only use this when each step actually needs a different model. Pattern 2: Router Router pattern — classify the task, route to the specialist: class ModelRouter : def __init__ ( self ): self . classifier = " qwen2.5-1.5b " self . specialists = { " code " : " qwen2.5-coder-7b " , " math " : " qwen2.5-32b " , " creative " : " claude-sonnet-4 " , " general " : " qwen2.5-7b " , } def route ( self , prompt : str ) -> str : task_type = self . classify ( prompt ) model = self . specialists . get ( task_type , self . specialists [ " general " ]) return self . call_m

There is a comfortable lie that has taken root in information security domain. It goes like this: "We have invested in the best tools. We have CSPM. We have CNAPP. We have ASM, ASPM, EDR, SIEM. We are covered." Boards believe it. CISOs present it. Security budgets are built around it. And while everyone is looking at dashboards full of green, two things are quietly true: One — attackers are not trying to beat your tools. They are looking for what your tools were never designed to see. Two — the most dangerous gaps in your security posture today are not gaps in your tooling budget. They are gaps in visibility, knowledge, and the fundamental understanding of what your own systems are supposed to do — and whether they actually do it. No tool solves that. Only people do. The Tool Trap The security industry has industrialized the idea that protection is a purchasing decision. Spend enough. Deploy enough. Integrate enough. And you will be secure. This thinking has produced something genuinely useful — a generation of powerful tools that automate detection, surface known misconfigurations, and reduce the manual burden on security teams. CSPM catches publicly exposed storage buckets. EDR detects malware. SIEM correlates suspicious behavior across logs. These tools matter and they work — within the boundaries of what they were designed to see. But there is a boundary. And most organizations have no idea where it is. The boundary is this: every security tool operates on known patterns, defined rules, and observable configuration state. None of them operate on context. None of them understand intent. And intent — what a system was supposed to do, how it was supposed to be accessed, what data it was never supposed to expose — is exactly where the most dangerous vulnerabilities live today. The Dangerous Gap Nobody Has Named Yet Security practitioners are familiar with the concept of IoM — Indicator of Misconfiguration. A wrong setting. An overpermissioned role. A flag that flipp

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