Chrome Extension Development

Chrome Extension Development Company For Manifest V3 Builds

An extension is a small product with a large amount of policy attached. Manifest V3 changed how background code runs, the Web Store reviews everything you ask for, and one over-broad permission can hold a release for days. We build for that reality from the first commit.

Triple Protection Guarantee

Triple Protection Guarantee:

Years In Business

0 +

Engineers On Staff

0 +

Avg. Engineer Exp.

0 +

Permissions Cut

Least Only

Senior Engineers

Vetted Only

Timezone Overlap

Live Hours

Built On MV3

Not Migrated

Delaware LLC

US Entity

Store Policy

Checked First

Quality Control

Code Review

Managed Deployment

Enterprise

Update Channel

Versioned

IP Assignment

Signed

Delivery Overlap

Fixed

Hours

Code & IP Owner

You

What A Chrome Extension Development Company Does

Chrome extension development is building software that runs inside the browser rather than on a page you own. It comes with its own platform rules: Manifest V3 replaced persistent background pages with service workers that stop when idle, remotely hosted code is not allowed, and every permission you request is read by a reviewer and shown to your users at install. A good extension asks for as little as it can and still does the job.

Stallyons is registered in Delaware as a US company, and our engineers work a time-zone window agreed before the project starts, with four-plus hours of daily overlap. You sign a US contract, run diligence on a US entity and pay one US invoice. Behind the work sits twelve-plus years of delivery across six continents and around thirty-five engineers, averaging four-plus years of production experience. Teams usually reach us when an internal tool now has to clear review, reach a whole estate, or survive the next Chrome release.

What An Extension Build Covers

A permission model decided on purpose: the narrowest host access the job needs, optional permissions requested at the moment they are used, and a written justification for each one that a store review can be answered with.

Manifest V3 architecture rather than a port: background work in a service worker that expects to be stopped and restarted, state held in storage instead of in memory, and alarms in place of long-lived timers.

Privacy answers prepared before submission: what data the extension handles and where it goes, in a disclosure that matches the code, because a mismatch between those two is what pulls a listing.

Enterprise deployment where you need it: force-install policy, managed configuration your IT team sets centrally, and a self-hosted update channel where a public listing is not appropriate.

Quality control you can inspect: code review on every merge, automated tests against the extension APIs, and work tracked on your board where you can read it without asking anyone.

One accountable vendor: one contract, one invoice and one entity for legal and finance to run diligence on, instead of a spread of contractors across four jurisdictions.

Why Teams Choose A Browser Extension Development Company

Ask which permissions the build will request, and why. Broad host access is the commonest reason a review stalls, and it is decided at design time rather than at submission.
Ask how background work survives the service worker stopping. Code written for Manifest V2 assumes it never stops, and that assumption fails without an error in real use.
Ask who answers the reviewer. You want a named person who has done it before, reachable inside your overlap window, rather than a shared inbox.
Ask what the privacy disclosure will say, then check it against what the code does. Those two drifting apart is what gets a listing removed rather than merely delayed.
Check the exit before you need it. The Web Store item, the developer account, the repository and the signing keys sit in your own name, so leaving is administration.
Ask what happens at the next Chrome release. Extensions break on platform changes, and somebody has to be watching the deprecation notices before your users are.

How A Chrome Extension Project Starts

Every project starts with a free 45-minute scoping session. No slide deck, no sales script. You bring the job the extension has to do and the users it is for; you leave with a build plan and a timeline.

We are selective about new projects and cap how many we run at once, because the scoping is the product. If the job is better done by a web app than by an extension, we will say so.

Why Clients Choose Us

Ready to ship an extension that clears review?

What We Build For Chrome

What Our Chrome Extension Development Covers

Every extension is a different job and the underlying pieces repeat: a surface in the browser, a background worker, a permission model and a route to your users. These are the builds we are asked for most often.

Productivity Toolbars

Shortcuts, capture, quick actions

In Toolbar

Page Enhancers

Content scripts on live pages

Right In Page

Data Extraction

Scrape, structure, export to CSV

Exported

SaaS Companion Apps

Your product, inside the tab

Live In Production

Auth & OAuth

Identity, tokens, refresh

Kept Signed

Enterprise Rollout

Policy install, managed config

Force-Set

APIs And Integrations

REST, webhooks, sync services

Linked

Web Store Submission

Listing, screenshots, review responses

Approved

MV2 To MV3 Migration

Background pages to service workers

Now Compliant

Cross-Browser Ports

Edge, Firefox, Safari variants

One Codebase

Not sure what an extension should own? Let us map it.

Common Challenges

Why Do Chrome Extensions Fail Review?

Six patterns behind almost every extension that stalls in review or breaks after a Chrome release. All six are avoidable.

01

The build asks for access to every site because that is easier during development, and nobody narrows it before submission. The reviewer sees a permission the description does not justify, and the release waits.

02

Code written for Manifest V2 assumes the background page never stops. Ported onto a service worker it looks fine on a developer machine and drops timers in real use.

03

State is held in a variable rather than in storage. The worker idles out, the variable is gone, and the extension forgets what the user was doing.

04

A script is pulled from a server at runtime to make updates easier. Manifest V3 does not permit remotely hosted code, so the listing is rejected regardless of the intent.

05

The privacy form is filled in from memory rather than from the code. The disclosure says one thing, the network requests say another, and the listing is pulled rather than delayed.

06

An API the extension relied on changes in a Chrome release. Nobody was reading the deprecation notices, so users report the breakage before the team sees it.

Recognise a few of these? Let us do it properly.

Our Extension Work

6 Chrome Extension Development Services

Six ways to buy extension engineering from one accountable vendor. Run one, or run several in parallel under a single contract.

01

A new extension built on Manifest V3 from the first commit, with the service it talks to built by our API development practice under one plan you approve.

02

Manifest V2 extensions moved onto V3 properly: background logic rebuilt for a service worker that stops, host permissions narrowed, and remote code removed rather than hidden.

03

Listing copy, screenshots, the privacy disclosure and a justification for every permission, prepared together so the review has less left to ask.

04

Force-install policy, managed configuration and a self-hosted update channel, so an extension reaches every machine in the estate without anyone clicking install.

05

The same product shipped to Edge, Firefox and Safari from one codebase, with the API differences handled in a compatibility layer rather than in three forks.

06

Watching the deprecation notices, testing against Chrome betas and shipping small updates, so a platform change becomes a routine release instead of an outage.

Not sure which piece you need first? Let us scope it together.

Why Choose Us

What Makes Our Chrome Extension Development Different

The details that decide whether an extension clears review and survives the next Chrome release.

01

Stallyons is registered in Delaware. Your contract, your invoice and your legal recourse sit with a US company, not an unknown one.

02

Permissions are designed before features, so the manifest asks for the narrowest access the job needs and every request has a written reason.

03

You choose the hours we share with your working day, and stand-ups, reviews and escalations all happen inside that window.

04

NDA and IP assignment are signed before any repository, credential or design file changes hands. Everything produced on the work is yours.

05

Every merge is reviewed against an agreed definition of done, on your board, where you can read it yourself.

06

One contract covers the engagement, so procurement, legal and finance each deal with a single named counterparty.

Ready to see what a clean extension build looks like?

Our Process

From First Call To Chrome Web Store In Six Steps

A process that settles permissions, policy and privacy answers before any code is written.

Discovery

Understand the job the extension has to do

Scoping

Agree the permissions, scope and cost

Design

Popup, options and in-page surfaces drawn

Contracting

NDA, IP assignment, access and onboarding

Deliver

Built, reviewed and packed for store

Review & Ship

Submit, answer the reviewer, then roll out

Want to see how this maps to your roadmap?

Technology Stack

The Full Stack Behind Our Chrome Extensions

Extension platform surfaces plus the engineering around them: identity, sync services and releases.

Who We Build This For

Chrome Extension Development For Every Kind Of Team

Eight kinds of team with different jobs and one shared need: something useful right where the work happens.

SaaS Product Teams

A companion to the main product

Sales & Outreach Teams

Prospecting, capture, sequences

Ecommerce Sellers

Pricing, listings, competitors

Education Tools

Reading aids, notes, accessibility

Marketing & SEO Teams

On-page data, audits, tagging

Security & Compliance

Policy checks in the browser

Enterprise IT Teams

Managed installs across estates

AI And LLM Product Teams

Assistants inside the browser

Working in another sector? See the industries we serve.

How We Compare

Your Chrome Extension Build Options, Compared

An honest look at your four delivery options.

Capability	Boilerplate Template	Solo Freelancer	Generalist Web Agency	Stallyons Technologies
Manifest V3 architecture	Often still V2	Varies widely	Learned on the job	Service workers by design
Permission scope	✕ All sites by default	Whatever is easiest	Rarely questioned	Narrowest that works
Web Store review handling	✕ Your problem	Sometimes included	First time for them	Justified before submitting
Privacy disclosure matches code	✕ Not addressed	Written from memory	Copied from a site	Written from the code
Enterprise managed deployment	✕ Out of scope	✕ Rarely known	If you ask	Force-install and policy
Edge, Firefox & Safari ports	Chrome only	Forked per browser	Quoted separately	One codebase, one layer
Store item & key ownership	Yours by default	Often their account	Varies by contract	Your account and keys

See the difference for yourself

Complete Engagement

Everything Included In Your Chrome Extension Build

From Scoping to Contracting to Delivery, One Vendor

Here is everything included when you build your extension with us:

🔒 No obligation. We'll deliver a detailed proposal within 48 hours.

Plus, Get These Free Bonuses

Free Extension Review

A written read on the permissions you are asking for, the Manifest V3 gaps in the current build and the privacy answers you will need. Yours to keep.

Included Free

Build Plan And Estimate

A phased build plan with scope, milestones, the integrations it needs and a transparent, itemised estimate for the engagement.

Included Free

Free Vendor Checklist

The questions we would ask any extension developer about permissions, service workers, privacy and store review, so you can test us on them too.

Included Free

Risk-Free Partnership

Our Chrome Extension Promise

We stand behind every engagement with commitments that protect your investment.

01 Scope Agreed First

Scope, model, working hours and cost structure are written down and agreed before contracting, so nothing is discovered later.

02 Built to Last

Senior developers, code review, automated tests, security and accessibility audits, and clean, documented code you fully own.

03 IP And Access Protected

NDA and IP assignment are signed before access, permissions are scoped per person, and your accounts stay under your control.

Start your Chrome extension build with confidence, backed by our Triple Protection Guarantee.

Track Record

Engagements That Ship, Scale, and Compound

500+

Projects Delivered

29+

Service Categories

81%

Repeat Client Rate

4.9 ★

Clutch Rating

"Stallyons took our Figma design and built it into a live web application, a cognitive game with level-based match play, messaging, a tutorial, and a directory that ranks users nationally. What impressed me most was their grasp of the code behind that logic, and the quality of the experience. Delivered on time with steady updates."

Jerry L.

Founder

PicCiti LLC

"We brought Stallyons in to absorb an overflow of work, and they delivered ten iOS and Android apps, from reporting to geo-location for logistics, plus several backend systems, owning design, development, and app-store submission. Everything stood out: code quality, speed, and reliability. Perfect code, on time, adopted company-wide."

William B.

Director

Amplo Solutions

FAQ

Frequently Asked Chrome Extension Questions

What is Chrome extension development?

Chrome extension development is building software that runs inside the browser and changes how people work with the pages they already visit. An extension has a manifest declaring what it may do, a service worker for background logic, content scripts that run on pages, and a popup or side panel for its own interface. Since Manifest V3 the platform is stricter: no remotely hosted code, and background logic that must expect to be stopped.

What changed in Manifest V3, and does it affect an existing extension?

Manifest V3 replaced persistent background pages with service workers that shut down when idle, banned remotely hosted code, and moved network rules to a declarative API instead of blocking requests in JavaScript. If your extension still runs on V2 it is affected, because Chrome has been disabling V2 extensions. The migration is a rebuild of the background layer rather than a manifest edit: state held in memory moves to storage, and long-lived timers become alarms.

How much does it cost to build a Chrome extension?

Cost follows how many surfaces the extension touches, whether it needs a backend, sign-in and sync, and how narrow the permissions can be made, so a figure before scoping is guesswork. Host permissions and the review work that follows move it most. We scope first, then price, and itemise each phase so you can cut before you commit rather than after.

How long does Chrome Web Store review usually take?

It varies, and nobody outside Google can promise a date, which is why we plan for it rather than around it. A first submission asking for broad host permissions attracts more scrutiny than a narrow one, and a privacy disclosure that matches the code removes the usual round of questions. We prepare the justification for every permission before submitting.

Who owns the code and intellectual property?

You do, from the first commit. NDA and IP assignment are signed before anyone gets repository access, with no licence-back and no shared ownership. The Chrome Web Store item, the developer account, the repository and the signing keys all sit in your own name, so moving the work elsewhere is administration.

Can you deploy an extension across our whole company?

Yes, and it is a different job from publishing publicly. Extensions can be force-installed through Chrome Enterprise policy and configured centrally with managed storage, so your IT team sets defaults without touching each machine. Where a public listing is not appropriate, we distribute through a self-hosted update channel instead, set up alongside the build.

How do you develop a Chrome extension safely?

Start from the permissions rather than the features. Decide what the extension may touch, request the rest optionally at the moment it is needed, and keep the manifest honest. Build background logic that assumes it will be stopped, hold state in storage, and never load code from a server. Then write the privacy disclosure from the code.

Should we build a Chrome extension or a web application?

Build an extension when the value lies in changing pages your users already visit, or in acting where their work happens. Build a web application when the product needs its own screens, its own data and its own account. Plenty of products want both, and the extension is then the thin part. See web application development.

Still have questions? Let's talk.

Schedule an appointment with us today!

Ready To Ship An Extension That Clears Review?

Get a free consultation. We will review the permissions, name the policy risks, and send you a written proposal.

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