From the OpenReplay Blog
Essential npm Commands Every Developer Should Know
The npm CLI covers dependency auditing, script execution, and transitive dependency pinning. Apply these commands to debug trees and fix vulnerabilities.
How to Lazy Load Components in Svelte
Lazy load Svelte components using dynamic imports and conditional rendering to keep initial bundles lean across SvelteKit and Vite-based projects.
How to Fix 'Cannot use import statement outside a module'
Fix the cannot use import statement outside a module error in Node.js, browsers, and Jest by diagnosing your module system mismatch correctly.
Chrome's Local Network Access (LNA) Permission Explained
Chrome Local Network Access permission gates public sites from reaching local devices. See what triggers the LNA prompt and how to handle it in your web app.
ASCII Art in the Browser and Terminal
How pixel brightness maps to characters, how Unicode Braille and block elements extend ASCII art, and how Canvas, WebGL, and ANSI terminals render it all.
How to Type API Responses in TypeScript
Typing API responses in TypeScript with interfaces, Zod schemas, and OpenAPI generation prevents runtime data mismatches and keeps types accurate.
Reactivity Models Compared: React, Vue, Angular, Svelte
Compare how React, Vue, Angular, and Svelte handle reactivity, from coarse-grained render cycles to fine-grained signals and compiler-driven DOM updates.
Ripple: A New TypeScript UI Framework to Watch
Ripple is a compiler-driven TypeScript UI framework that eliminates virtual DOM diffing and manual dependency tracking with fine-grained reactive primitives.
How to Implement Drag and Drop in Svelte
Implement drag and drop in Svelte using the native HTML5 API or svelte-dnd-action to handle animations, touch support, and multi-list boards.
Use Cases for JavaScript Generators
JavaScript generators produce values on demand for lazy iteration, async pagination, and composable pipelines using the Iterator Helpers API.
When 100vh Lies: Fixing Mobile Viewport Issues
Fix mobile viewport clipping by understanding how svh, dvh, and lvh units differ from vh and when to apply each for stable full-height layouts.
How to Organize Type Definitions in a TypeScript Project
Organize TypeScript type definitions effectively by applying a clear colocation strategy across inline files, shared directories, and ambient declaration files.
MCP Apps: Adding Interactive UI to AI Conversations
MCP Apps enable interactive UI components inside AI conversations. See how MCP servers render dashboards and forms using the ext-apps SDK standard.
A Better Way to See Errors in VS Code with Error Lens
Error Lens brings ESLint and TypeScript diagnostics inline in VS Code, helping frontend developers spot and fix errors faster without leaving the editor.
Building Your First API with Koa
Build a REST API with Koa by setting up routing, parsing JSON bodies, and applying the middleware cascade model to handle GET and POST endpoints.
When to Use user-select: none (and When It's a UX/Accessibility Trap)
Know exactly when CSS user-select none helps interactive controls and when it harms accessibility, translation tools, and users who rely on text selection.
How to Measure JavaScript Performance
Profile JavaScript execution with DevTools, the Performance API, and Core Web Vitals to identify bottlenecks and measure real user INP accurately.
Virtual Scrolling for High-Performance Interfaces
Virtual scrolling renders only visible DOM nodes, keeping large datasets fast. See how windowing, overscan, and libraries like TanStack Virtual work.
OpenClaw: A New Open-Source AI Assistant
OpenClaw is a self-hosted AI agent that executes shell commands, controls browsers, and integrates with Slack, Telegram, and WhatsApp on your own hardware.
Streams Explained for Web Developers
Process fetch responses chunk by chunk using the Web Streams API, ReadableStream, and TransformStream to reduce memory pressure and improve performance.
How Key-Value Databases (e.g., Redis, Memcached) Work
Redis, Memcached, and key-value databases use in-memory hash tables for fast lookups, caching, and session storage in frontend-facing backend systems.
What Is Lynx.js? A Beginner's Guide
Lynx.js is a cross-platform framework from ByteDance that renders native iOS and Android UIs using React, real CSS, and a dual-thread architecture.
Absolute Values in CSS with abs()
The CSS abs() function handles signed custom properties safely in spacing, animation timing, and layout math without requiring JavaScript workarounds.
Building Type-Safe API Clients with OpenAPI and TypeScript
Generate TypeScript types from OpenAPI specs using openapi-typescript, openapi-fetch, and Orval to build type-safe API clients and eliminate runtime errors.