Chrome Extensions That Ship and Stay Approved
Chrome extension development for businesses and developers. I build Manifest V3 Chrome extensions with popup UIs, background workers, content scripts, and AI integrations. Philippines-based, available for remote projects worldwide.
Chrome extension development has a hidden complexity ceiling.
Chrome extensions seem straightforward until they are not. Content scripts that break on specific sites, service worker lifecycles that terminate at the wrong moment, permissions that trigger store rejection, and Manifest V3 APIs that behave differently than the documentation suggests. These are not beginner mistakes — they are architectural traps that experienced developers fall into without extension-specific expertise.
Most extension developers build against a handful of test sites and call it done. The problems surface in production: the extension does not work on sites with strict Content Security Policy, it loses state when the service worker is suspended, or it gets rejected in Chrome Web Store review for avoidable policy violations.
Chrome extensions built with real-world edge cases in mind.
I build Chrome extensions that work correctly on the sites that matter to your users — including sites with strict CSP, single-page applications, and enterprise environments. Every extension ships Manifest V3 compliant with proper service worker lifecycle management and permission justifications ready for store review. Based in Davao City, Philippines, I deliver remotely with clear async communication across US, AU, and EU timezones.
- Manifest V3 compliant from the first commit — no migration debt accumulated
- Tested on 50+ real-world target sites before store submission
- Service worker lifecycle handled correctly — no silent state loss in production
- Chrome Web Store submission with all listing assets and permission justifications
- TypeScript throughout — typed Chrome APIs, typed storage schemas, typed messages
What I Build For You
Productivity Extensions
Extensions that eliminate repetitive tasks from the browser workflow — custom keyboard shortcuts, form autofill, page modifications, quick-capture notes, and workflow automation triggered inside any site.
Shopping Tools
Price comparison overlays, coupon finders, product review aggregators, and purchase history trackers that activate on shopping sites and surface savings without breaking the checkout flow.
Developer Tools
DevTools panel extensions, API response inspectors, environment switchers, CSS debuggers, and request interceptors that slot into the Chrome DevTools workflow for engineering teams.
Content Tools
Reading mode, text highlighting, annotation layers, content filtering, readability enhancements, and page-to-PDF converters that modify how users experience any web page.
Privacy Extensions
Tracker blocking, cookie managers, fingerprint protection, request filtering, and privacy audit tools that give users control over what data leaves their browser session.
Business Extensions
CRM data capture from LinkedIn and Gmail, lead enrichment overlays, time trackers on client sites, and internal tooling extensions deployed to teams via Chrome Enterprise policy.
Transparent Pricing, No Retainer Required
One-time project fee
A focused single-feature Chrome extension ready for Chrome Web Store submission.
- Single-feature Manifest V3 Chrome extension
- Popup UI with basic settings
- One content script for page interaction
- Chrome Storage sync for user preferences
- Chrome Web Store submission assets
- 2 weeks post-launch support
One-time project fee
A multi-feature extension with external API integration, full settings UI, and store publication.
- Multi-feature extension with service worker
- Full options and settings page UI
- External API or AI model integration
- Secure credential storage pattern
- Background sync and alarm-based scheduling
- Chrome Web Store submission with all assets
- 30 days post-launch support with check-ins
Scoped per project
Team-deployed extensions with enterprise policy, backend integration, and user management.
- Chrome Enterprise policy deployment
- Backend API with user authentication
- Admin dashboard for team configuration
- Side panel and DevTools panel extensions
- CI/CD pipeline for auto-publishing updates
- Usage analytics and error monitoring
- Retainer option for ongoing development
From Extension Idea to Chrome Web Store
Scope and Permission Design
We define exactly what the extension does, which sites it runs on, and which Chrome APIs it uses. Permission scope is designed minimal from the start — this decision locks in before code is written.
Architecture Blueprint
Extension architecture designed around Manifest V3 constraints: service worker event lifecycle, declarativeNetRequest for request blocking, content script isolation, and background message passing patterns.
TypeScript Development
Extension built in TypeScript with typed Chrome API wrappers, typed storage schemas, and typed message passing. Build pipeline configured with webpack or Vite for clean production output.
Real-World Testing
Extension loaded in Chrome and tested against the actual sites in scope — including SPAs, sites with strict CSP, and enterprise environments. Every user-facing flow is validated on real pages.
Store Submission and Delivery
Chrome Web Store developer account submission with screenshots, promotional tile, detailed description, and permission justification text. Source code, build instructions, and documentation delivered at handoff.
What Makes These Extensions Survive in the Real World
Service Worker Lifecycle Handled
The most common MV3 bug is state loss when the service worker is suspended. I use Chrome Alarms, message passing, and Chrome Storage to persist state correctly so the extension behaves reliably after the worker wakes up.
CSP-Compatible Content Scripts
Many sites run strict Content Security Policy that blocks inline scripts and external resources. Content scripts are written to inject DOM modifications safely without triggering CSP violations on the target pages.
TypeScript Throughout
All Chrome extension APIs are typed. Storage schemas are typed with Zod validation. Message types are typed with discriminated unions. This eliminates an entire class of runtime bugs common in untyped extension code.
Minimal Permission Footprint
Every permission is justified against actual feature requirements. Extensions with over-broad permissions face store rejection and user trust warnings. Minimal permissions are audited before every submission.
Async-First Delivery
Based in Davao City, Philippines (UTC+8). Projects run async-first with Loom demos of working builds, written progress updates, and GitHub access. US, AU, and EU clients get full visibility without live scheduling.
Store Submission Included
Every build includes Chrome Web Store submission: screenshots at required dimensions, promotional images, store description optimized for search, privacy policy language, and permission justifications. No extra charge.
Chrome Extensions Shipped, Developers Unblocked
"We needed a Chrome extension that captures lead data from LinkedIn and syncs it to our CRM. Previous developers had gotten it working on basic profiles but failing on Sales Navigator pages. Johnbert fixed the content script architecture and handled the SPA navigation changes correctly. It has worked on every page type since."
"Our privacy extension was rejected twice by the Chrome Web Store before we came to Johnbert. He audited the permissions, rewrote the network request handling to use declarativeNetRequest as required, and submitted with proper justification text. Approved on the first attempt after his revision."
"JB built a DevTools panel extension for our API debugging workflow. The panel integrates with our backend, shows request context, and lets engineers replay calls with modified headers. Exactly what we needed and built with clean TypeScript that our own team has been able to extend."
Chrome Extension Development Questions, Answered
Johnbert Oñez
AI Solutions Engineer & Full Stack Developer · 6+ yrs · 50+ projects
Based in Davao City, Philippines. Specialises in production AI systems, full-stack web applications, and WordPress. Remote-first, async-friendly, fixed-fee projects.
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