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When a Spring Boot service needs to talk to another service without waiting on a synchronous HTTP call, message queues are the usual answer. Apache Kafka has become the default choice for this in most backend teams, but a lot of tutorials stop at a "hello world" producer and consumer that would never survive a real production load. Things like consumer retries, error handling, serialization of real objects, and graceful shutdown get skipped, and those are exactly the parts that page you at 2 a.m. In this tutorial, you will build a Spring Boot application that produces and consumes JSON messages over Kafka. You will configure a producer and a consumer, send a typed object instead of a plain string, handle deserialization errors so one bad message does not block your whole consumer group, and verify the whole thing works end to end. By the end, you will have a small but realistic messaging setup you can build on. Prerequisites To follow along, you will need: Java 17 or later installed. You can check your version by running java -version . A Spring Boot 3.x project. You can generate one at start.spring.io with the Spring for Apache Kafka dependency added. A running Kafka broker. The quickest way to get one locally is Docker, which the first step covers. Basic familiarity with Spring Boot, including how @Component and application.yml work. Step 1 — Running Kafka Locally with Docker Before writing any code, you need a broker to talk to. Running Kafka by hand involves Zookeeper, broker configuration, and a fair amount of setup, so you will use Docker Compose to bring up a single-broker cluster instead. Create a file named docker-compose.yml in your project root: services : kafka : image : apache/kafka:3.7.0 container_name : kafka ports : - " 9092:9092" environment : KAFKA_NODE_ID : 1 KAFKA_PROCESS_ROLES : broker,controller KAFKA_LISTENERS : PLAINTEXT://:9092,CONTROLLER://:9093 KAFKA_ADVERTISED_LISTENERS : PLAINTEXT://localhost:9092 KAFKA_CONTROLLER_LISTENER_NAMES : CONTRO

Gas optimization is satisfying. You shave a few thousand gas off a function and feel clever. But some optimizations trade away safety in ways that are not obvious, and I have seen "optimized" contracts that introduced vulnerabilities. Here are the gas wins that are genuinely free, the ones that cost you safety, and how to tell the difference. Where gas actually goes Before optimizing, know what is expensive. Storage operations dominate. Writing a fresh storage slot ( SSTORE from zero to non-zero) costs a lot; reading storage ( SLOAD ) is cheaper but still meaningful; computation in memory is cheap by comparison. So the highest-leverage optimizations are about touching storage less. Free win 1: cache storage reads in memory If you read the same storage variable multiple times in a function, each read is an SLOAD . Read it once into a local variable instead: // WASTEFUL: reads storage `total` three times function distribute() external { require(total > 0, "empty"); uint256 share = total / count; emit Distributed(total); } // OPTIMIZED: one SLOAD, two memory reads function distribute() external { uint256 _total = total; // single storage read require(_total > 0, "empty"); uint256 share = _total / count; emit Distributed(_total); } This is free in the sense that it changes nothing about correctness. The value is identical; you just read it once. Pure win. Free win 2: calldata instead of memory for read-only arrays For external function arguments you only read (never modify), calldata is cheaper than memory because it skips the copy: // memory copies the whole array into memory function process(uint256[] memory ids) external { ... } // calldata reads directly from the transaction data, no copy function process(uint256[] calldata ids) external { ... } Again, free. If you do not mutate the array, calldata is strictly better. Free win 3: storage packing Solidity packs multiple variables into one 32-byte slot if they fit and are adjacent. Order your storage variables so smal

1. Python Ortam Kontrolü (Windows CLI) Python sürüm kontrol python --version py --version where python pip kontrol pip --version python -m pip --version pip güncelleme (kritik) python -m pip install --upgrade pip 2. Python Çalıştırma Mekanizması (Windows Standard) Script çalıştırma python app.py Py launcher ile sürüm seçme py app.py py -3 .12 app.py py -3 .11 app.py Modül çalıştırma python -m mymodule 3. Sanal Ortam (venv) – Kurumsal Standart Oluşturma python -m venv venv Aktivasyon (PowerShell) venv \S cripts \A ctivate.ps1 Aktivasyon (CMD) venv \S cripts \a ctivate.bat Deaktivasyon deactivate Sanal ortam kontrol where python where pip pip list 4. requirements.txt Yönetimi Oluşturma pip freeze > requirements.txt Kurulum pip install -r requirements.txt Güncelleme pip install --upgrade -r requirements.txt 5. Paket Yönetimi (pip Core Set) Paket yükleme pip install requests Versiyon sabitleme pip install requests == 2.31.0 Paket kaldırma pip uninstall requests Listeleme pip list Güncellenebilir paketler pip list --outdated 6. Windows .env Yönetimi (Konfigürasyon Standardı) .env dosyası oluşturma notepad .env Örnek içerik DEBUG=True API_KEY=123456 DB_URL=localhost Python tarafı (.env kullanımı) pip install python-dotenv from dotenv import load_dotenv import os load_dotenv () api_key = os . getenv ( " API_KEY " ) print ( api_key ) 7. Sistem Komutları ve Process Yönetimi Process listeleme tasklist Python process filtreleme tasklist | findstr python Process sonlandırma taskkill /PID 1234 /F Python process kill taskkill /IM python.exe /F 8. Dosya İşlemleri (CLI seviyesinde) Dosya listesi dir Klasör değiştirme cd project Dosya silme del file.txt Klasör silme rmdir /S /Q folder 9. Log ve Debug Yönetimi Dosya log izleme (PowerShell) Get-Content app.log -Wait Son satırlar Get-Content app.log -Tail 100 Filtreleme Select-String "ERROR" app.log 10. Uzaktan Erişim (Windows → SSH) SSH bağlantı ssh user@server_ip Dosya gönderme scp app.py user@server_ip:C: \U sers \u ser \ Klasör gön

If you've ever felt like LangChain was too heavy, you're not alone. The dependency tree is enormous. Abstraction layers pile up. At some point you lose track of what's actually happening underneath. That frustration has pushed a lot of people toward lighter alternatives — frameworks that prove you can build a capable agent without a hundred transitive dependencies. Agno is one of those alternatives. It started as Phidata and rebranded in early 2025. I spent an afternoon installing Agno v2.6.17 in a clean sandbox and running through Calculator tools, Wikipedia retrieval, Pydantic structured output, and a two-agent Team. I'll share the real execution logs and, more importantly, the traps I hit that the docs don't warn you about. What Agno Is and Where It Came from Phidata built a solid reputation as "the Python framework for AI assistants." When it rebranded to Agno in 2025, the design philosophy got articulated more clearly around three ideas. Model-agnostic from day one. Over 70 LLMs — OpenAI, Anthropic, Google, Ollama, Cohere — can plug in with the same code structure. Swap the model, keep the agent logic. Multimodal as a default. Text, image, audio, video agents all use the same API surface. You don't need a different abstraction layer for each modality. Multi-agent orchestration as a first-class citizen. The Team class is built in. You can switch between coordinate , route , and collaborate modes with a single parameter change. Reading that, I thought: "How is this different from LangChain?" The answer showed up when I actually wrote code. Agno favors composition over class inheritance. One agent takes about 6 lines to set up. There's far less boilerplate to wade through. Installation: No Dependency Hell pip install agno google-genai ddgs wikipedia The agno package installs just the core. Tools require their own extra dependencies — wikipedia for the Wikipedia tool, google-genai for Gemini. This lazy-loading approach keeps the base install clean. $ python3 -c "im

One of the challenges I faced while building my LaTeX Writer project was implementing version control and project forking in a storage-efficient way. A typical LaTeX project contains multiple files. Even a simple project usually has a "main.tex" file, bibliography files, images, style files, and other supporting documents. If I stored a complete copy of every file for every version or fork, storage requirements would grow rapidly. Imagine a project with four files and ten versions. Storing the entire project for every version would mean storing the same files repeatedly, even when only one line changed. Forking would create an even bigger problem because every fork would require another complete copy of the project. Instead of accepting this inefficiency, I started researching how large platforms solve the same problem. GitHub was the obvious inspiration. Learning from GitHub GitHub does not store a complete copy of a repository every time a change is made. Instead, it stores content separately and uses references to connect files, commits, and repositories. This idea became the foundation for my own implementation. Project Structure Whenever a new project is created, a default file called "main.tex" is generated automatically. The project itself does not directly contain file contents. Instead, it stores metadata such as: Project ID Owner ID Root Folder ID File References Each file also has its own metadata record containing: File ID File Name Blob ID Project ID Owner ID Folder ID The actual content is not stored inside the file metadata. Instead, the content lives inside a separate entity called a Blob. Loading a Project When the editor loads a project, it reconstructs the directory structure using metadata. The process works like this: Retrieve the project's Root Folder ID. Find all folders belonging to that folder hierarchy. Find all files belonging to each folder. Build the directory tree for the frontend. Because files and folders are stored independently, the

📚 Limn Engine — Complete API Reference Quick Navigation Class Purpose Level Display Canvas, game loop, input, camera, scenes 🟢 L1 Component Every visible game object 🟢 L1 Camera Viewport control (follow, shake, zoom) 🟡 L2 move Movement, physics, particles, helpers 🟢 L1 state Read-only query helpers 🟢 L1 TileMap Grid-based levels 🟡 L2 Tctxt Rich text with backgrounds 🟢 L1 Sound Single audio file 🟢 L1 SoundManager Multiple sounds, volume control 🔴 L4 ParticleSystem Emit, burst, continuous emitters 🟠 L3 Sprite Spritesheet animation 🟡 L2 Display The heart of every Limn Engine game. Creates the canvas, runs the game loop, captures input, manages the camera, and controls scenes. Constructor const display = new Display (); Properties Property Type Description .canvas HTMLCanvasElement The game canvas .context CanvasRenderingContext2D 2D drawing context .keys Array Boolean array indexed by keyCode .scene Number Current active scene (default 0) .camera Camera Attached camera instance .deltaTime Number Time since last frame (seconds) .fps Number Current frames per second .frameNo Number Total frames elapsed .x / .y Number false Methods Method Parameters Description .start(w, h, node) width, height, parentNode Initialise canvas and start game loop .perform() — Activate dual-canvas pipeline (call before .start() ) .add(comp, scene) Component, scene number Register a Component for rendering .stop() — Pause the game loop .scale(w, h) width, height Resize canvas after start .backgroundColor(color) CSS color Set background colour .lgradient(dir, c1, c2) direction, color, color Linear gradient background .rgradient(c1, c2) color, color Radial gradient background .fullScreen() — Enter fullscreen .exitScreen() — Exit fullscreen .tileMap() — Build TileMap from display.map and display.tile Usage const display = new Display (); display . perform (); display . start ( 800 , 600 ); display . backgroundColor ( " #0a0a2a " ); const player = new Component ( 40 , 40 , " blue " , 100 , 100 ); d

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

The first two articles in this series each showed one technique. Implementation notes #001 was a dynamic dropdown — a form field that fills itself from an API. Implementation notes #002 was a dynamic credential — an API key that arrives from the form and threads through to the HTTP nodes. This article is the capstone. It walks through all-services-demo , the example workflow that ships with n8n-nodes-ldxhub , where those two techniques combine with a Switch node to host five different AI document-processing services inside one workflow — structured extraction, translation refinement, OCR, PDF conversion, and text extraction. The screenshots and the workflow JSON below come from the n8n-nodes-ldxhub package. The patterns themselves are generic — they work for any set of services you want to consolidate into a single template. This is not a "follow these steps" article. It's a parts catalog. No two readers are solving the same problem, and templates rarely fit anyone's situation as-is. Take what fits. Drop the rest. You don't need to understand all 46 nodes to reuse the patterns. The shape The workflow has 46 nodes — large enough to look intimidating in the editor, but structurally it's just five repeated paths plus a small routing section. The entry section is two nodes: On form submission — the trigger. Asks the user which service they want and collects an API key. Route by Service — a Switch node with five outputs, one per service. Everything to the right of the Switch is service-specific. Five paths fan out: StructFlow, RefineLoop, RenderOCR, CastDoc, ExtractDoc. Each path ends in two Form Ending nodes — one for success (auto-downloads the result), one for error. That's the spine: form → switch → service path → ending. The complexity is pushed into the service paths. The spine: routing by static comparison The Switch node ("Route by Service") uses Rules mode. Each rule reads the same expression from the form — {{ $json.service }} — and compares it to a static serv

Most developers run git pull dozens of times a week without thinking about it. And most of the time, it works. Then one day you open a PR and the reviewer says "can you clean up the merge commits?" You look at your branch and see three "Merge branch 'main' into feature/login" commits scattered through history. The feature itself is 5 commits. The log is a mess. That mess comes from one decision: using git pull instead of git pull --rebase . Here's what's actually happening, and why the rebase variant produces cleaner history for teams. The setup: diverged history You're working on feature/login . You commit two changes locally ( X , Y ). Meanwhile, your teammate pushes two commits to main ( C , D ). Your branch and main have now diverged . Neither is a strict superset of the other. Git needs to reconcile them when you pull. Shared history: A → B Your local: A → B → X → Y (you added X, Y) Remote main: A → B → C → D (teammate added C, D) Git has two strategies for this reconciliation. Strategy 1: git pull (merge) A plain git pull creates a merge commit that joins your local history with the remote. Your commits and the remote's commits both appear in the log, connected by a merge node. The git log reads: M Merge branch 'main' into feature/login D fix: timeout on slow connections Y feat: client-side validation C chore: upgrade eslint X feat: login form B (shared) A (shared) This is honest history — it records exactly what happened: parallel development that was joined at a specific point. But it's also noisy history — the merge commit has no meaningful changes, and the log interleaves commits that weren't conceptually related. Strategy 2: git pull --rebase With --rebase , Git takes a different approach. It: Temporarily sets aside your local commits ( X , Y ) Fast-forwards your branch to the tip of the remote ( D ) Replays your commits on top, one by one, creating new commits ( X' , Y' ) The git log reads: Y' feat: client-side validation X' feat: login form D fix: timeo

Ask a language model to score a developer portfolio out of 100 and you get a confident number back. Hand it a near-empty page with a name and a broken avatar, and it will often still tell you something like 92. Nice layout. Strong personal branding. The model is being polite, not accurate. That was the first wall I hit building Leon, the reviewer inside getfolio. If the score is not trustworthy, nothing downstream matters: the critique, the suggestions, and the fix button all hang off a number the model invented to sound encouraging. This is the build log of how I stopped letting the model hold the pen. Short version: a deterministic rules engine owns the score, and the language model only owns the words around it. The failure mode: an LLM judge wants to be liked If you have shipped anything with an LLM evaluator you have probably seen this. You hand it a rubric, a JSON schema, even worked examples, and it still drifts upward. Empty inputs get encouraging scores. Weak inputs get the benefit of the doubt. Strong inputs land in the same band as the weak ones, just with longer praise. A few reasons, roughly in order of how much they hurt: Tuning rewards a helpful, encouraging tone. Harsh scoring reads as unhelpful, so the model softens it. The model has no ground truth for what a 70 versus an 85 looks like in your specific domain. It is scoring on vibes. Scoring and explaining are entangled. The model writes the kind explanation first, then picks a number to match the nice things it just said. Run it twice on the same input and you get two different numbers. There is no anchor. For a portfolio reviewer that real recruiters and developers would act on, that was a non-starter. If Leon says 64, an empty page should not be able to reach 64 by accident, and a strong portfolio should not get talked down to it either. The number has to mean something. The fix: rules engine owns the score, model owns the language The architecture splits responsibilities hard. A deterministic e

If you're shipping a commercial WordPress plugin, sooner or later you'll need a licensing system. Something that lets paying customers activate the plugin on their site, locks it to that domain, and stops people from sharing the same key across fifty sites. The default answer in the WordPress world is Freemius or EDD Software Licensing. They're great. They're also a revenue share, a third-party dependency, and a black box you don't control. When we built RideCab WP , a commercial WooCommerce taxi booking plugin, we decided to build our own. Here's the architecture, the code, and the gotchas we hit along the way. What a Licensing System Actually Needs to Do Before writing any code, get clear on the requirements. A real plugin licensing system needs to: Generate unique license keys when someone buys Let the customer activate the key on their site Bind that key to one (or N) domains Validate the key periodically so revoked or expired keys stop working Handle deactivation when a customer moves to a new domain Fail gracefully — never lock a paying customer out because your license server hiccuped Optionally: deliver plugin updates only to valid license holders We'll cover 1 through 6 in this post. Update delivery is a separate beast and I'll write it up next. The Architecture The system has two halves that live in two different places. The license server runs on your own infrastructure — for us, it's a WordPress must-use plugin (mu-plugin) on the same WordPress install that powers our marketing site. It: Stores license keys in a custom database table Exposes a small REST API for activate, deactivate, and validate calls Provides an admin dashboard to view, create, and revoke keys The client is a PHP class shipped inside the commercial plugin (RideCab WP, in our case). It: Adds a license settings page to the plugin Calls home on activation Caches the validation result Re-validates quietly in the background Two pieces, talking over HTTPS, with the customer's domain as the b

json.loads(response) fails at a certain point. You told the model "return JSON only," but it added a ```json markdown code fence around everything. A quick regex strips it — until that regex hits an edge case, and that edge case blows up in production. Since Ollama 0.3.0, passing a JSON schema to the format parameter eliminates this problem at the root. The model's inference itself is constrained by the schema, so no code fences, no explanatory text, no mid-thought artifacts. Just parseable JSON. I ran these tests locally with Gemma4 and Ollama 0.30.7 to see how well it holds up in practice. Why LLM Response Parsing Is Tricky The most common problem when running Ollama locally — without a cloud LLM API — is JSON parsing. Two reasons. First, text generation models are trained toward "natural text." Even if you ask for JSON only, they'll often wrap it in json ... blocks or prepend "Of course! Here is the JSON you requested:" style text. Here's what I reproduced directly: json Input: 'Give me 3 Python tips as JSON with keys: tips (array), difficulty (1-5)' Model output (no format parameter): ```json { "tips": [ "Master the fundamentals first...", ... ] } JSON parse: FAILED Python ' s `json.loads()` can ' t handle the markdown wrapper . The " JSON only " instruction is unreliable in production . Second , speed . I measured the same query both ways : 32 seconds without structured output , 5 seconds with it . More on why below . ## How the Ollama format Parameter Works Ollama ' s `/api/generate` endpoint has a `format` field. Pass a JSON schema object and Ollama applies **constrained decoding** during inference. python import json import urllib.request def ollama_structured(prompt, schema, model="gemma4:e4b"): payload = { "model": model, "prompt": prompt, "format": schema, # ← pass JSON schema object directly "stream": False, "options": {"temperature": 0} } data = json.dumps(payload).encode() req = urllib.request.Request( " http://localhost:11434/api/generate ", data=data

🚀 Technical Briefing: This tutorial is part of our deep-dive series on Agentic Workflows at Gate of AI . For the full technical breakdown, interactive code sandbox, and the native Arabic translation, visit the original article here . <span>Tutorial</span> <span>Advanced</span> <span>⏱ 45 min read</span> <span>© Gate of AI 2026-06-16</span> Learn how to fine-tune large language models (LLMs) to enhance communication capabilities in specialized domains, such as homeless shelters, using modern AI tools and techniques like LoRA. Prerequisites Python 3.10+ OpenAI API key (latest version) Familiarity with machine learning concepts What We're Building In this tutorial, we will embark on a journey to fine-tune a large language model (LLM) to cater to the specific communication needs of homeless shelters. By leveraging a bespoke dataset compiled from the Youth Spirit Artworks (YSA) Tiny House Empowerment Village website, we aim to create a model that can effectively assist in the nuances of communication required in such environments. The finished project will result in a model capable of generating contextually relevant and empathetic responses to inquiries typical within the homeless shelter community. This involves structuring data into a standardized question-and-answer format to enhance the training process, ensuring the model's outputs are aligned with the communication style and needs of the target audience. Setup and Installation To begin, we need to set up our development environment with the necessary tools and libraries for model fine-tuning. We'll be using Python along with the OpenAI library to interact with the LLMs. pip install openai pandas numpy Additionally, you'll need to configure environment variables to securely store your API keys. This ensures that sensitive information is not hardcoded into your scripts. .env file OPENAI_API_KEY=your_openai_api_key Step 1: Data Collection and Preparation The first step in fine-tuning our model involves collecting and

Quick Tip: How to Choose the Right Model for Slack AI Workflows in 2026 I've been running Slack-integrated AI workflows in production for about three years now, and the question I get asked most often is deceptively simple: "Which model should I actually use?" Back in 2024, the answer was easy — you picked GPT-4o and moved on. But in 2026, with 184 models accessible through Global API and price points ranging from $0.01 to $3.50 per million tokens, that decision has become a genuine engineering problem. Pick wrong and you're either burning budget or shipping a sluggish experience. Pick right and your CFO actually smiles at you. Let me walk you through how I think about this, what the numbers actually look like, and where I've landed after months of benchmarking across multi-region deployments. Why Slack Workloads Are Weird Most people underestimate what a Slack AI assistant needs to do well. It's not a chatbot. It's a latency-sensitive, always-on, context-heavy workload that has to feel native inside a chat client where users expect responses faster than they can refresh the channel. In my experience, the three constraints that matter most are: p99 latency under 1.5 seconds for the first token — anything slower and users start double-messaging 99.9% uptime across at least two regions — Slack itself is up, so your AI better be too Cost per active user per month under $0.40 — this is the line where finance stops asking questions If a model can't hit those numbers consistently, it's not viable, no matter how clever the benchmark scores look. The Pricing Landscape I Actually Use Here's the table I keep pinned in my team's documentation. These are the models we rotate between depending on the workload. I haven't changed a single number — these are the exact rates as of writing this: Model Input ($/M) Output ($/M) Context DeepSeek V4 Flash 0.27 1.10 128K DeepSeek V4 Pro 0.55 2.20 200K Qwen3-32B 0.30 1.20 32K GLM-4 Plus 0.20 0.80 128K GPT-4o 2.50 10.00 128K The spread is w

Here is a problem I hit building a long-running agent: I needed to inject a new instruction partway through a session ("the project is Go, write Go") but editing the top-level system prompt to add it invalidated my entire prompt cache. Every cached turn got reprocessed at full price. The fix is a feature that landed in the current Claude models: mid-conversation system messages. Here is what it is and when to use it. The setup that breaks A long agent session has a large, stable system prompt and a growing message history, and you cache the prefix so each turn reuses the prior work cheaply. That works until you learn something mid-session that the agent needs to know: a mode toggled, the user delivered async context, files changed on disk, the token budget dropped. The naive move is to edit the system prompt to include the new fact. But the system prompt sits at the front of the cached prefix. Change one byte there and you invalidate everything after it. Your whole conversation history reprocesses at full input price on the next request. For a long session, that is expensive and slow. The fix: a system message in the messages array The current models let you put a system -role message directly in the messages array, after the history, instead of editing the top-level system : const response = await client . messages . create ( { model : " claude-opus-4-8 " , max_tokens : 16000 , system : [ { type : " text " , text : STABLE_SYSTEM , cache_control : { type : " ephemeral " } }, ], messages : [ ... history , // cached prefix, untouched { role : " user " , content : latestUserMessage }, // @ts-expect-error: role:"system" SDK types may still be landing { role : " system " , content : " This project is Go. Write all code in Go. " }, ], }, { headers : { " anthropic-beta " : " mid-conversation-system-2026-04-07 " } }, ); Because the new instruction sits after the cached history, it invalidates nothing before it. The cached prefix stays intact, you pay full price only for the

An AI agent has two kinds of memory: conversation (semantic) and context (exact reference). Keep them separate with Strands and AgentCore.

Local SEO rankings are not the same everywhere. Your website may rank in position 2 in Austin, position 8 in Dallas, and not appear at all in Chicago. That is why checking one generic Google result is not enough for local SEO. If you are working on local SEO , agency reporting, competitor monitoring, or location-based search analysis, you need to track rankings by city. A simple workflow looks like this: Keyword + city → SERP API → local search results → ranking check → CSV report In this tutorial, we’ll build a basic Python script that tracks local SEO rankings by city using a SERP API. We will: Define target keywords Define target cities Send city-specific searches to a SERP API Extract organic results Check where a target domain appears Save the ranking data to CSV This is not a full SEO platform, but it gives you the core logic behind many local rank tracking tools. Why city-level rankings matter Google search results are location-sensitive. A query like: best digital marketing agency may return different results in: New York Austin London Singapore Sydney This matters even more for local intent keywords, such as: dentist near me plumber in Chicago coffee shop in Austin real estate agent in Miami For these searches, the result page can include: organic results local packs Google Maps results ads business directories review sites service pages location-specific landing pages If you only check one location, you may miss what users actually see in other cities. For local SEO, ranking data without location context is incomplete. Why use a SERP API? You could try to check Google rankings manually. But that does not scale. You could also try to scrape Google directly, but that brings a lot of maintenance work: changing page layouts CAPTCHA blocked requests proxy handling inconsistent HTML location mismatch parser updates retry logic A SERP API gives you structured search results in JSON. Instead of parsing raw HTML, you get data like this: { "query" : "plumber in Aust

Yesterday, as I was working on a CORS configuration, AI generated a block of code for me: const allowedOrigins = [ process . env . FRONTEND_URL || " http://localhost:3000 " , process . env . ADMIN_URL || " http://localhost:3001 " , ]. filter ( Boolean ); I was wondering... why use .filter(Boolean) here? 🤔 The fallbacks already guarantee strings. So I hovered on the variable. The type definition read: const allowedOrigins : string [] Fine. Made sense. But then I got curious. What if I removed the hardcoded fallbacks? const allowedOrigins = [ process . env . FRONTEND_URL , process . env . ADMIN_URL , ]. filter ( Boolean ); My type definition changed to: const allowedOrigins : ( string | undefined )[] I was shocked. I just filtered the array. How can TypeScript still think there's an undefined in there? First: What Does .filter(Boolean) Even Do? Boolean used as a filter function removes any falsy value from an array: false null undefined 0 "" NaN So: [ " https://app.com " , "" , undefined ]. filter ( Boolean ) // Result: ["https://app.com"] At runtime, this works exactly as you'd expect. No undefined survives. So why does TypeScript disagree? 🤷‍♀️ The Real Answer: TypeScript Doesn't Run Your Code TypeScript is a transpiler. It doesn't execute .filter(Boolean) — it only looks at types. When it sees this: array . filter ( Boolean ) It knows the callback returns a boolean . But it doesn't know what that means for the type of the elements that survive. It can't infer "if Boolean(x) is true, then x must be a string." So the undefined stays in the type — even though it'll never actually be there at runtime. That's the gap: your runtime behavior is correct, but your types are lying. The Fix: Type Predicates TypeScript lets you close that gap with a type predicate — a way of explicitly telling the compiler what a filter function guarantees: const allowedOrigins = [ process . env . FRONTEND_URL , process . env . ADMIN_URL , ]. filter (( origin ): origin is string => Boolean ( o

A connected Gmail grant starts with an OAuth consent screen and ends with a refresh token you have to babysit; a Nylas Agent Account starts and ends with one POST request. Same API surface afterward — same messages endpoints, same webhooks, same calendar — but the provisioning story couldn't be more different, and that difference is what makes these hosted mailboxes such a natural fit for Python automation, agents, and test harnesses. Agent Accounts are in beta, and the official quickstart gets you from nothing to a sending-and-receiving mailbox in under 5 minutes using curl. Here's the whole flow as a Python script. Step 0: prerequisites You need an API key (run nylas init with the CLI, or use the Dashboard) and a domain. The fast path for testing: register a *.nylas.email trial subdomain from the Dashboard — no DNS records, instantly usable. Custom domains need MX and TXT records published at your DNS provider, with automatic verification once they propagate; save that for production. import os import requests BASE = " https://api.us.nylas.com " HEADERS = { " Authorization " : f " Bearer { os . environ [ ' NYLAS_API_KEY ' ] } " , " Content-Type " : " application/json " , } Step 1: provision the account POST /v3/connect/custom with "provider": "nylas" . No refresh token — just an email address on a registered domain: resp = requests . post ( f " { BASE } /v3/connect/custom " , headers = HEADERS , json = { " provider " : " nylas " , " settings " : { " email " : " test@your-application.nylas.email " }, }, ) resp . raise_for_status () grant_id = resp . json ()[ " data " ][ " id " ] print ( f " Agent Account live: { grant_id } " ) Save that grant_id — per the docs, you'll use it in every subsequent call. The mailbox works with every existing endpoint from this moment on. If you want policies or mail rules applied, add a top-level workspace_id to the same request body; the account inherits the workspace's limits, spam settings, and rules. Omit it and the account lands i

Provisioning a working email mailbox from Node.js takes less code than the average OAuth callback handler. No consent screen, no token refresh job, no provider SDK — one fetch call returns a grant ID, and from there the mailbox sends, receives, and RSVPs to calendar invites. That's the pitch for Nylas Agent Accounts , hosted email-and-calendar identities you control entirely through the API. They're in beta, and the official quickstart promises a working account in under 5 minutes. The docs show it in curl; here's the same flow in JavaScript. What you need Two things: an API key, and a registered domain for the mailbox to live on. For testing, the zero-DNS path is a *.nylas.email trial subdomain registered from the Dashboard — addresses like test@your-application.nylas.email work immediately. For production you'd register your own domain (the Dashboard generates the MX and TXT records to publish, and verification is automatic once they propagate), but the trial domain is fine for this walkthrough. export NYLAS_API_KEY = "nyk_..." Create the mailbox The endpoint is POST /v3/connect/custom — the same Bring Your Own Auth route used for other providers — with "provider": "nylas" . Unlike OAuth providers, there's no refresh token in the body; just the address: const BASE = " https://api.us.nylas.com " ; const headers = { Authorization : `Bearer ${ process . env . NYLAS_API_KEY } ` , " Content-Type " : " application/json " , }; const res = await fetch ( ` ${ BASE } /v3/connect/custom` , { method : " POST " , headers , body : JSON . stringify ({ provider : " nylas " , settings : { email : " test@your-application.nylas.email " }, }), }); const { data } = await res . json (); const grantId = data . id ; // save this — every later call needs it That grantId is the whole handle. The mailbox behind it is live as soon as the response comes back, and it works with every existing endpoint — messages, drafts, folders, calendars, events, webhooks. One optional field deserves a menti