A URL shortener may handle millions of redirects per second.Each redirect is also a click event we want to count. But there’s a challenge: Redirects must be ultra fast, while stats storage is write-heavy....
When building large-scale systems (like URL shorteners, distributed caches, or databases), we often use consistent hashing to decide which server stores which data. But consistent hashing alone isn’t enough. To make it truly scalable...
When designing a large-scale URL shortener (like Bitly), the biggest challenge isn’t storing URLs — it’s serving billions of redirects with low latency. The solution? Multi-layer caching. This article explains how caching works across...
f you’ve ever built a web API or MCP (Model Context Protocol) server, you’ve probably encountered mysterious OPTIONS requests appearing in your server logs. Or worse, you’ve seen CORS errors in the browser console blocking your perfectly valid requests. Today, we’ll demystify CORS preflight requests and show you why they’re essential for secure web applications. What...
# Why Your Password Comparison is Leaking Secrets Ever written code like this? “`java return storedPassword.equals(providedPassword); “` It looks harmless, but it has a critical security flaw. Let me explain. ## The Problem with...
Most people think MCP streaming disappeared when SSE was deprecated. That is wrong. Streaming did not go away — permanent connections did. This article explains how Streamable HTTP works and why it is superior...
If you’ve ever looked at MCP server code and thought: “Why does this need both GET and POST?Why does the server reply on SSE instead of POST?Why is SSE now deprecated but examples still...
# Understanding Checkpoints in LangGraph: State Snapshots, Time-Travel, and Human-in-the-Loop ## What is a Checkpoint? A **checkpoint** is a snapshot of your workflow’s state at a specific point in time. Think of it like...
Building a simple AI agent with LangChain4j is easy. But add real-world requirements and it falls apart: Suddenly you’re writing while loops, tracking state manually, parsing agent responses, and praying nothing breaks. Real Example: Text-to-SQL Requirements: LangChain4j approach: 78 lines of orchestration code for a simple workflow. LangGraph4j: Define the Flow, Not...
# LangGraph4j Integration Specification ## Table of Contents 1. [Why LangGraph4j?](#why-langgraph) 2. [Core Concepts](#core-concepts) 3. [Java Implementation Example](#java-example) 4. [ColdFusion Integration Proposal](#coldfusion-integration) — ## 1. Why LangGraph4j? {#why-langgraph} ### The Problem: Traditional Workflow Limitations...