Blog
Mert Özen's blog posts on software development, backend, frontend, and DevOps.
Files and Binary Data in JavaScript: File, Blob, ArrayBuffer and Typed Arrays
We take files from the user via input and drag and drop, read Blobs and Files, go down to bytes with ArrayBuffer, typed arrays and DataView, and learn ES2026's base64/hex methods and file downloads.
JavaScript Observer APIs: Intersection, Mutation and Resize Observer
We build lazy loading and infinite scroll with IntersectionObserver, watch DOM changes with MutationObserver and element size with ResizeObserver, and learn how to clean observers up properly.
JavaScript Web Workers: postMessage, Transferable Objects and Module Workers
We move heavy work off the main thread with Web Workers and learn postMessage and structured clone, single-file Blob URL workers, transferable objects, module workers and life without the DOM.
JavaScript Performance Tips: Debounce, Throttle and Layout Thrashing
We learn to measure with performance.now, mark and measure, write our own debounce and throttle, and cover requestAnimationFrame, layout thrashing, lazy loading and the DevTools Performance tab.
JavaScript Memory Management: Garbage Collection, Memory Leaks and WeakRef
We look at the stack and heap, reachability and garbage collection, then cover leaks from forgotten listeners, timers, closures and detached DOM, plus WeakMap, WeakRef and heap snapshots in DevTools.
JavaScript Proxy and Reflect: Traps, Validation and Reactivity
We intercept reads, writes and deletes on an object with Proxy and keep default behavior with Reflect, then build validation, default values and a reactive UI while covering the pitfalls and the cost.
JavaScript Async Iterators: for await...of, Async Generators and Array.fromAsync
We walk through data that arrives over time with Symbol.asyncIterator and async generators, learn for await...of and ES2026's Array.fromAsync, read a paginated API as a stream and meet ReadableStream.
JavaScript Iterators and Generators: Symbol.iterator, yield and Iterator Helpers
We cover the iterable and iterator protocols, writing your own iterable with Symbol.iterator, how generators and yield pause and resume, infinite sequences, ES2025 iterator helpers and ES2026's Iterator.concat.
Advanced JavaScript Async Patterns: The Promise.all Family, Cancellation, Retry and Timeouts
We look at the differences between Promise.all, allSettled, any and race, ES2024's Promise.withResolvers, ES2025's Promise.try, supporting AbortSignal in your own functions, retry, timeouts and concurrency limits.
The JavaScript Event Loop in Depth: Tasks, Microtasks and Rendering Order
We work through output-order puzzles to see the task and microtask queues, where promises and queueMicrotask fit, when requestAnimationFrame runs in the rendering step, and why long tasks freeze the page.
JavaScript OOP Patterns: Inheritance or Composition? Factory Functions and Mixins
We talk about the cost of inheritance, combining behavior with composition, factory functions and mixins, choosing between closures and #private, the SOLID principles that fit JavaScript, and when a class is worth writing.
JavaScript Object Protection and Immutability: Property Descriptors, seal and freeze
We look at property descriptors, the sneaky defaults of Object.defineProperty, the difference between preventExtensions, seal and freeze, shallow versus deep freezing, and patterns for updating objects without mutating them.