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Carl Victor Fontanos
Carl Victor Fontanos

Carl Victor Fontanos

Software Engineer

I build web applications and share what I learn along the way.

© 2026

Tutorials

128 tutorials

Step-by-step programming tutorials on PHP, JavaScript, Laravel, WordPress and more.

JavaScript Advanced

A 15-Line Proxy That Tells You Exactly What Changed

Dirty checking, undo history, "unsaved changes" warnings - all reduce to knowing when an object changed. Proxy intercepts the writes themselves, no framework needed.

2 min 1,629
JavaScript Advanced

for await...of: Paginated APIs as a Simple Loop

Async generators hide the pagination bookkeeping - cursors, hasMore flags, page counters - behind a clean loop that fetches pages only as you consume them.

2 min 1,656
PHP Intermediate

A Real Upload Progress Bar with XMLHttpRequest and PHP

fetch() still cannot report upload progress reliably - but XMLHttpRequest has done it for fifteen years. The full pattern: progress events, a PHP receiver, and the config limits that silently break big uploads.

2 min 2,920
jQuery Intermediate

One Global Spinner for Every AJAX Call

Stop wiring loading states into every request. jQuery broadcasts global AJAX lifecycle events, and $.ajaxSetup injects headers everywhere - CSRF tokens included.

2 min 3,548
jQuery Advanced

Write Your Own jQuery Selectors like :external

jQuery lets you define custom pseudo-selectors - :external, :blank, :offscreen - that work in every $() call, filter() and delegation rule in your codebase.

2 min 690
PHP Advanced

Real-Time Updates with Plain PHP: Server-Sent Events

WebSockets need infrastructure. Polling hammers your server. SSE streams live updates over normal HTTP with a PHP file and the built-in EventSource API - reconnection included.

2 min 1,859