What it is
jQuery is a JavaScript library created by John Resig. It wraps the browser's document model, events and AJAX calls in one short, consistent API, which mattered a great deal when every browser behaved a little differently. For years it was the default way to add interactivity to a web page, and a huge plugin ecosystem grew around it.
Modern browsers now offer most of what jQuery smoothed over, and component frameworks like React handle complex, stateful screens better. Plenty of working business systems still depend on it, though, so being able to read, maintain and gradually replace jQuery code remains a useful skill for anyone taking over an older application.
How I use it
- Part of the Brikers stack, alongside PHP, MySQL, SuiteCRM, Twilio and Cordova.
- Listed among the older technology I still read when modernizing: PHP, CodeIgniter, jQuery, MySQL, Flex and Flash-era systems.
- Moving systems off it the same way Rental Pilot moved: old and new side by side, one screen at a time.
jQuery is still a fair choice for small scripts on a server-rendered page. For a screen with a lot of changing state I would choose React now. I keep jQuery on the list because a lot of the systems I am asked to modernize were built with it, and reading them is the first step in replacing them safely.
Questions
Can you maintain our jQuery application?
Yes. I built with jQuery at Brikers and still read jQuery-era systems. I can keep one running and, when it makes sense, move it to React a screen at a time.
Should we rewrite our jQuery app all at once?
Usually not. Rental Pilot's legacy UI was replaced screen by screen while the business kept running, and that approach carries less risk than a big-bang rewrite.