Private corporate batches, live online cohorts and 1-on-1 mentoring in maintaining, securing and modernising jQuery codebases that are still in production — taught by a practitioner who runs it in production.
20 years across DevOps, SRE and Security · 10,000+ engineers trained · Trained teams at JPMorgan Chase, Verizon, Nokia and the World Bank
Principal DevOps Engineer & Architect
Rajesh teaches jQuery as maintenance engineering rather than as a first library — the wrapped set and chaining model, the traversal and manipulation APIs, and the event system including delegation and the deprecated methods that older code depends on. Sessions concentrate on what a team inherits: auditing a large undocumented codebase, upgrading through 1.x, 2.x and 3.x with the Migrate plugin, closing the cross-site scripting advisories that dependency scans raise, and replacing the library incrementally with native APIs behind tests rather than in a rewrite.
Twenty years across DevOps, SRE and Security, in principal and architect roles at PayPay, SoftwareAG, ServiceNow, JDA Software, Intuit, Adobe and others. He has trained engineers at JPMorgan Chase, Verizon, Nokia, the World Bank, VMware, Oracle, Mercedes-Benz and Airbus — more than 10,000 people personally. He teaches what he runs, not what he reads.
You are booked with a named engineer, and that is who turns up. Marketplaces and larger providers rotate whoever is free, so the person who sold you the agenda is rarely the person teaching it.
The same trainer is available for the next engagement, which matters when a team builds on what it learned last time.
Your batch is assigned a named trainer before it starts, and that is who teaches it. See the full faculty.
Engagements are matched on the tool, not the calendar. For jQuery that means a trainer who has run it in production — maintaining, securing and modernising jQuery codebases that are still in production — rather than whoever is free that week. You are told who is teaching before you commit, and that person is on the discovery call that shapes the agenda.
Where a batch is large enough to need a second trainer, the pairing is declared up front. The lead trainer stays accountable for the syllabus and the assessment either way.
Principal DevOps Engineer & Architect
Twenty years across DevOps, SRE and Security in principal and architect roles at PayPay, SoftwareAG, ServiceNow, JDA Software, Intuit, Adobe, IBM/Emptoris, Ness, MindTree and Accenture. He has trained more than 10,000 engineers personally, at organisations including JPMorgan Chase, Verizon, Nokia, the World Bank, VMware, Oracle, Mercedes-Benz and Airbus. He teaches what he runs, not what he reads.
Teams of 8–30
Custom agenda, your timezone, onsite or online, NDA-friendly.
Request a quoteIndividual engineers
A private instructor and a curriculum built around your goal.
₹99,999Individuals who want peers
Scheduled batch, max 8 to 10 hours of live instruction.
₹34,999A private batch starts with a discovery call. We look at the stack you actually run — the CI system, the cloud, the constraints — and map the agenda onto it, so examples use your topology rather than a generic one.
Delivery is onsite at your premises, live online, or hybrid, scheduled around your release calendar rather than ours. Batches run 8 to 30 engineers.
Every attendee leaves with recordings, slides, lab repositories and a completion certificate. You receive an attendance and assessment report. Invoicing supports PO and GST.
Talk to us about a private jQuery batchjQuery is a JavaScript library that wraps DOM elements in a chainable object and provides a uniform API for selection, traversal, manipulation, events, effects and Ajax. It was written for a browser landscape where attaching an event handler or making an HTTP request required different code in every engine, and it solved that problem so thoroughly that it became the default way to write client-side JavaScript for roughly a decade.
The design is small and consistent. The dollar function returns a wrapped set — zero or more elements plus every method the library defines — and because most methods return the set, calls chain. Selection uses CSS selector syntax with extensions, traversal moves around the DOM tree, manipulation edits content, attributes and classes, the event layer normalises the event object and supports delegation, and dollar-dot-ajax provides a request API with deferred objects for composition.
The honest position today is that jQuery is legacy. Everything it was invented to normalise is now native: querySelectorAll, classList, addEventListener, fetch, promises, and CSS transitions all do what the library did, without a dependency. New projects should not adopt it. But jQuery still ships on a very large share of existing sites, plugins and admin interfaces, and those codebases need engineers who can read them, patch them, keep them on a supported version, resolve the security advisories that affect the older releases, and retire them piece by piece rather than in a risky rewrite.
The reason to learn jQuery in 2026 is not to start a project with it. It is that an enormous amount of running software is built on it — internal admin tools, WordPress and CMS themes and plugins, vendor products, reporting portals and line-of-business applications written between 2008 and 2018. That code still has bugs, still needs features, and still fails security scans.
Those scans are the immediate pressure. Older jQuery releases carry published cross-site scripting advisories, and a dependency audit will flag them regardless of whether the application team considers the library important. Upgrading through the 1.x, 2.x and 3.x line involves genuinely breaking changes, and the deprecated event and effect APIs that older code leans on were removed rather than merely discouraged. Someone has to plan that work.
The skill organisations are short of is not writing new jQuery — it is reading a large, undocumented jQuery codebase, understanding what it does, adding tests around the behaviour, upgrading it safely, and replacing it incrementally with native APIs where the risk is justified. That is maintenance engineering, and it is exactly what this course is built to deliver.
An honest starting point. What jQuery is and the browser problems it was written to solve, what the platform now does natively, and the decision framework for maintaining, upgrading or retiring it. Then the practical setup — versions, the slim build, CDN against bundled installation, and the JavaScript basics the library assumes.
Topics: What jQuery is, why it existed and what replaced each of its jobs · Choosing between maintain, upgrade and retire for a real codebase · Versions 1.x, 2.x and 3.x, and the slim build · Installing from a CDN, from npm and through a bundler · The dollar function, document ready and script placement · noConflict and coexisting with other libraries · JavaScript basics jQuery assumes — strings, numbers, booleans, arrays, functions
The object model everything else builds on. Element, id and class selectors and the wider selector syntax, what the wrapped set actually contains, how to get back to a raw DOM node, why chaining works, and the selector patterns that quietly cost performance on large pages.
Topics: Element, id and class selectors · Attribute, filter and form selectors · The jQuery object versus a raw DOM element, and get and index access · Length, emptiness and safely handling a zero-length set · Chaining and the methods that break a chain · Scoping a selector to a context · Selector performance and caching selections
Moving around the document from a starting set — the part of jQuery that is genuinely more ergonomic than the native API and therefore the hardest to remove. Traversing up, down and sideways, filtering a set, and the iteration methods that older code uses everywhere.
Topics: Traversing up the DOM tree — parent, parents and closest · children and find · siblings, next, nextAll and nextUntil · first, last and eq · filter and not · each and iteration over a set · Native equivalents — parentElement, closest, children and matches
Changing what is on the page. Getting and setting attributes and properties, applying styles, class manipulation, then content manipulation and structural editing — insertion, replacement, removal and cloning — including the injection risk that makes the html method the most dangerous call in the library.
Topics: Getting and setting attribute values, and attr versus prop · Applying styles — setting a single and multiple CSS properties · Class manipulation and data attributes · Content manipulation — text, html and val · A callback function for attr and other setters · Inserting elements — append, prepend, after and before · Adding several new elements with after and before · DOM element replacement, removal, empty and clone · Why html with untrusted data is a cross-site scripting defect
The largest part of most jQuery codebases. The on and off API, the full shorthand set, the normalised event object, and delegation — which is why jQuery code scales to dynamic content. Then the deprecated methods older code is full of, and what each translates to today.
Topics: on, off, one and the ready event · Mouse events — click, dblclick, mousedown, mouseup, mouseenter, mouseleave, mousemove, hover · Keyboard and form events — keydown, keypress, keyup, change, select, submit, focus, focusin, focusout, blur · Window events — load, resize, scroll and unload · The event object — target, currentTarget, delegateTarget, relatedTarget, pageX, pageY, which, type, timeStamp, data, namespace · preventDefault, stopPropagation, stopImmediatePropagation and their isolated checks · Event delegation with on and a selector · Deprecated and removed — bind, unbind, live, die, delegate, undelegate, toggle, error · trigger, triggerHandler and custom events
The visual layer and its cost. Hide, show and toggle, the fade and slide families, custom animation with relative and predefined values, the queue and how to stop it, callbacks and chaining — and an honest comparison against CSS transitions, which do the same work on the compositor.
Topics: hide, show and toggle · fadeIn, fadeOut, fadeToggle and fadeTo · slideDown, slideUp and slideToggle · Custom animation with animate, relative values and predefined values · How the effects queue works, and the stop method · Callback functions and method chaining · jQuery.holdReady, jQuery.proxy and other utility helpers · CSS transitions and animations as the better default
How jQuery codebases talk to servers. The dollar-dot-ajax settings object and the shorthand methods, loading simple data into an element, deferred objects and their promise-like composition, error and status handling, form serialisation and headers — then the mapping from each of these to fetch.
Topics: Loading simple data and the load method · The ajax method and its settings object · Shorthand methods — get, post, getJSON and getScript · Deferred objects, then, done, fail and always · The jqXHR object, status codes and error handling · Serialising forms and sending JSON · Headers, CSRF tokens and credentials · Cross-origin requests and what jQuery does not change about CORS · Mapping each jQuery Ajax call to its fetch equivalent
The ecosystem around the library, which is usually where the real complexity lives. Writing a plugin on the fn namespace with options and defaults, the advanced jQuery UI widgets and how to customise them, and integrating with other libraries and frameworks including load order, dependency and conflict problems.
Topics: Writing a plugin on the fn namespace · Options, defaults and per-element state · Publishing and versioning an internal plugin · Advanced jQuery UI widgets — sortable, draggable and resizable · Customising and theming widget behaviour · Integrating with third-party libraries such as Bootstrap · Handling conflicts, dependencies and script load order · Auditing an unmaintained plugin before you depend on it
Making an inherited codebase behave. Debugging techniques with browser developer tools, logging and error handling, then the performance work — caching, delegation, debouncing and throttling, lazy loading — and cross-browser compatibility through feature detection, polyfills and graceful degradation.
Topics: Debugging jQuery with browser developer tools and breakpoints · Logging strategy and global error handling · Advanced performance — caching selections and minimising reflow · Debouncing and throttling high-frequency handlers · Lazy loading and deferred initialisation · Memory leaks from retained handlers and detached nodes · Cross-browser compatibility — feature detection over browser sniffing · Polyfills and graceful degradation
The work most teams actually need. Auditing usage across an estate, upgrading through the version line with the Migrate plugin, closing the security advisories a dependency scan raises, moving from CDN to a managed dependency, and replacing the library incrementally behind tests rather than in a rewrite.
Topics: Auditing jQuery and plugin usage across an application estate · Breaking changes across 1.x, 2.x and 3.x · The jQuery Migrate plugin and reading its warnings · Known cross-site scripting advisories and what a dependency scan reports · Subresource integrity, and moving from CDN to npm and a bundler · Characterisation tests around existing behaviour before refactoring · Incremental replacement with querySelectorAll, classList, addEventListener and fetch · The strangler approach — retiring the library page by page · Deciding when retirement is not worth funding
We rebuild the agenda around the tools you actually run.
Request a custom agendaTake an undocumented jQuery application, map its selectors, handlers, Ajax calls and plugins, and produce a behaviour inventory a new maintainer could work from.
Convert deprecated bind, live and delegate calls to the on API, replace per-row handlers with delegation, and add namespacing so teardown is clean.
Work through the cross-site scripting advisories a dependency scan raises, remove unsafe html calls, and upgrade to a supported release with Migrate warnings resolved.
Port an Ajax-heavy module from dollar-dot-ajax and deferreds to fetch with promises, keeping error handling, headers and status behaviour identical.
Profile a slow jQuery page, cache selections, throttle handlers, move animation to CSS, and produce before and after measurements from DevTools.
Write characterisation tests around existing behaviour, replace the library page by page with native APIs, and deliver a costed plan for the remainder.
Billed yearly at ₹9,996
Max 8 to 10 hours of live instruction
Full program, private instructor
8–30 engineers · custom agenda · onsite or online · PO and GST invoicing
Refunds. If we cancel or postpone a cohort, you get a full refund within 15 days. There is no money-back guarantee otherwise.
Terms. Course material remains licensed to the attendee. Read the terms.
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Certificate of completion
Great learning experience from a very knowledgeable instructor with well-prepared course notes. The lab exercises on AWS instance work well to learn the hands-on side of the course.
Rajesh is a very good trainer I have experienced in DevSecOps training. The number of contents in different topics he has posted on the DevOpsSchool public website are amazing and user friendly for beginners and experienced professionals.
The trainer (Rajesh) provided very good sessions on SRE profession. Not only hands-on learning on the tools but also SRE mindset.
Very good training session. Well explained from the basics to the complex concepts. Also tried to cover practicals and demos within the 3 hour sessions. The learning content and videos are of a great deal of help.
Basics explanation was exemplary from Rajesh where he dealt with complicated topics to be simple. Great learning stuff personally for me.
Very detailed explanation and has lots of patience in attending the questionnaire. Thanks again for your wonderful sessions.
| What matters | YouTube + blogs | Generic online course | Freelance marketplace | DevOpsSchool |
|---|---|---|---|---|
| Named practitioner | No | Rarely | Varies per booking | Yes — same trainer each time |
| Production experience | Unknown | Unknown | Unverified | 20 years, named employers |
| Custom agenda | No | No | Sometimes | Built from your stack |
| Onsite delivery | No | No | Sometimes | Yes |
| Lab environment | None | Sandbox that expires | Varies | Your own cloud — skill goes with you |
| Assessment | None | Quiz | Rarely | Assignments + capstone per module |
| Per-attendee certificates | No | Sometimes | Rarely | Yes |
| Corporate invoicing | No | Limited | Varies | PO and GST |
| Post-training support | None | Forum, time-limited | None | Lifetime forum access |
Tell us the team, the stack and the timeline. You'll get a straight answer, not a sales sequence.
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