Karan Mahajan
Developer.
I build fast, scalable web applications — and I use AI to do it better.
A developer who ships — and keeps shipping.
I'm Karan Mahajan, a full-stack web developer based in Ontario, Canada. Over five years and across two countries, I've worked in agency, in-house, and independent settings — building production applications that range from headless CMS architectures to AI-integrated SaaS platforms. I hold a Master's in Applied Computing from the University of Windsor, where I also contributed as a Programming Research Assistant on a client-facing platform redesign.
My primary stack is Next.js, React, TypeScript, and GraphQL, with strong command of WordPress, Drupal, and headless CMS patterns on the content side. On the backend, I work comfortably with Node.js, Python, PostgreSQL, MongoDB, and Django, and I've led integrations across Stripe, WooCommerce, ERP systems, JWT/OAuth authentication, and REST APIs. I write SCSS, enforce BEM, and care deeply about component architecture — having built and published reusable npm packages with cross-framework support across React, Angular, and Vue.
Beyond the code, I've owned performance audits and Core Web Vitals improvements, implemented CSP and CORS security standards, ensured WCAG accessibility compliance, and set up CI/CD pipelines using AWS and Jenkins. I've worked in Agile environments using Jira and Confluence, and I bring the same structured thinking to independent and contract work.
I treat AI as a practical tool — embedded into how I review code, structure content workflows, and approach problems upstream of implementation.
Experience & Education
Five years across two countries — agency, in-house, and independent.
Full Stack Web Developer
- Built scalable CMS-driven and headless architectures using WordPress and Drupal, integrating with Next.js via REST and GraphQL to deliver flexible, high-performance web applications
- Developed modern frontend applications with React and Next.js (SSR, SSG, ISR), improving performance, SEO, and user experience while supporting scalable SaaS platforms
- Customized themes, plugins, and backend systems using CPTs, taxonomies, WP-CLI, and hook-based architecture, streamlining workflows and enhancing content management efficiency
- Led complex integrations including Stripe (payments, subscriptions, webhooks) and WooCommerce with ERP systems, managing data pipelines, authentication (JWT/OAuth), and role-based access
- Strengthened application performance, security, and accessibility through caching, code splitting, Core Web Vitals optimization, WCAG compliance, and best practices like CSP, CORS, and SEO implementation
Programming Research Assistant
- Led the frontend redesign of a client-facing platform, improving usability, navigation, accessibility, and overall user experience while aligning with business requirements
- Built dynamic, data-driven UI components and integrated RESTful APIs (Velo by Wix) to enable real-time dashboards, seamless frontend-backend communication, and enhanced user engagement
- Managed CMS-driven architectures across Wix and WordPress, handling structured data, customer profiles, dynamic content, and implementing SEO best practices for improved search visibility
Master of Applied Computing
Software Engineer
- Led development of a reusable React component library, integrating with Node.js and MongoDB backends while ensuring WCAG-compliant accessibility standards
- Built and published reusable component packages (npm + Stencil.js), enabling cross-framework support (React, Angular, Vue) and reducing integration time across projects
- Implemented robust testing and documentation using Jest and Storybook, improving component reliability, usability, and design-developer collaboration
- Maintained high-quality frontend architecture using TypeScript, SCSS, BEM, and responsive design, while managing code with Git/Bitbucket and Agile workflows (Jira, Confluence)
Software Craftsperson
- Developed responsive web applications and PWAs using React, Next.js, HTML, and CSS, improving user engagement and mobile retention through optimized UI/UX
- Built dynamic dashboards and custom UI components (BEM, Material UI) to enhance data visualization, scalability, and maintainability
- Integrated Node.js APIs with MongoDB backends, ensuring efficient data flow, system reliability, and seamless frontend-backend communication
- Deployed and optimized applications using nginx and Vercel, while performing end-to-end testing to ensure performance, stability, and high-quality user experience
Member of Technical Staff
- Managed and optimized MySQL databases by writing efficient SQL/PL-SQL queries, procedures, and packages, ensuring data accuracy, performance, and quick resolution of production issues
- Developed and enhanced frontend features using JavaScript, HTML, and CSS, including form validations and UI improvements for core product functionality
- Contributed to backend development using Java, implementing new features (e.g., multi-attachment forms) and improving system scalability and reliability
- Streamlined deployment and testing workflows using AWS and Jenkins CI/CD pipelines, while performing end-to-end testing and handling change requests, bug fixes, and Jira-based production support
Skills
Tools I use in production every week — grouped by where they live in the stack.
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Projects
Scroll to flip through the deck — each card pins until the next one takes over.
findabl
findabl is a full-stack SaaS platform I designed and built single-handedly to help businesses improve their visibility across AI-powered search tools like ChatGPT, Gemini, Perplexity, and Microsoft Copilot. I shipped the entire customer-facing product solo in [N weeks] — Next.js 16 App Router, React 19, TypeScript, Tailwind CSS 4, Supabase, Stripe, and SendGrid — covering the full journey from marketing and authentication through billing, onboarding, and a post-subscription dashboard. Visitors register with server-side reCAPTCHA v3, choose a Starter or Growth plan, acknowledge a dynamically generated PDF service agreement, and check out through Stripe, with webhooks keeping Supabase in sync and firing automated welcome emails and activity logs. On the technical side I built dual AI-powered business search on GPT-4o-mini and Gemini 2.5 Flash with IP-based rate limiting, promotional flows with auto-applied Stripe coupons matched by email, and marketing pages cached with Next.js's "use cache" directive on week-long TTLs and Suspense skeletons for fast loads.
Alectra Utilities
I built and maintained a large-scale, multi-brand enterprise web platform serving two major Ontario utilities — Alectra Utilities and Guelph Hydro — powering their public sites, customer portals, and a shared UI component library consumed by third-party billing and account-management apps. The hardest part was integration: I engineered custom Drupal modules exposing dynamic header/footer and billing endpoints that external JSP applications rendered live, so two separately-built systems looked and behaved like one product. I stood up full-text search on Apache Solr with advanced filtering and spellcheck, and delivered a responsive, multi-brand front-end on a custom Foundation theme with multi-region layouts, inline alerts, and accessible navigation. The platform runs on Pantheon with enterprise caching and is hardened to utility-sector security standards (CSP, 2FA, and bot/spam protection) for reliability at scale.
AI Writing Assistant
I built a native macOS writing assistant that lives in the system tray and drafts replies in my own voice across Teams, Outlook, JIRA, Confluence, GitHub, and ChatGPT. The hard problem was reading on-screen context without browser scraping or extensions — I solved it with Swift accessibility helpers calling the macOS Accessibility API directly, then stream replies from the Claude API tuned to a personal style guide and memory file. Three triggers cover every surface: a selection popover for grammar and rewrites, a proactive compose bubble above multi-line inputs, and a global overlay window. To preserve rich email formatting I write Outlook replies via synthesized CGEventPost keystrokes instead of flattening the content, and the API key never leaves the OS keychain. Built with Electron, Node.js, and Swift.
Interstone
I designed and built a custom WordPress theme for Interstone, a premium building-materials company, turning a 1500+product catalogue into a polished, fully responsive browsing experience with no transactional layer. The interesting constraint was using WooCommerce purely as a catalogue engine — I stripped all cart and checkout UI so users could explore products by category and filter by material, colour, and finish, with live search returning instant results as they type. The standout feature is an AI-powered Visual Search page where users upload a photo of their space and get relevant product recommendations back. Under the hood I built a strict SCSS token system on Bootstrap 5 with a Gulp pipeline (compilation, autoprefixing, minification, source maps) and seven reusable Gutenberg blocks on ACF Pro, so the client can compose pages without touching code.
Alectra Corporate Website
I led the Drupal 10 → 11 major-version migration for Alectra Inc.'s corporate website — one of Ontario's largest electricity distributors, serving over 1 million customers — upgrading the platform across a 60+ component, paragraph-based content system with no loss of content or layout. On top of the migration I owned frontend and custom module development end to end, building three custom Drupal modules covering automated cache management, employee document handling, and security headers, all on a fully custom Foundation for Sites theme. The 60+ reusable components let the client's editors assemble new pages — careers listings, data-sheet sections, CTA layouts — entirely from the CMS without developer involvement.
WEAL Website
Developed and designed a comprehensive website using Wix, enabling efficient sample submission and result management. Implemented an admin dashboard for streamlined sample analysis and results uploading, improving overall administrative workflow
Campus Cart
I built Campus Cart, a university marketplace web app on Django, Python, and PostgreSQL, restricted to verified staff and students so on-campus trading stays inside a trusted community. Users list and browse items across categories with email-authenticated profiles, full-text search, and a map view that surfaces listings by location.
News Article Recommender
Developed a news article recommender system with Python (Pandas) and NLP, featuring a React JS UI and MongoDB storage. Enhanced user engagement through personalized recommendations and Tableau visualizations of user data interactions
Let's work together
Got a product to build, a team to augment, or just a sharp idea worth prototyping? I read everything.