Disclosure: ThemeSweep is built by JMS Dev Lab, the publisher of this blog. We will be honest about where Cleanify Code works fine and where ThemeSweep does something genuinely different.
You install a Shopify app. It injects code into your theme — Liquid snippets, JavaScript files, CSS blocks, sometimes entire template overrides. The app works great for a while. Then you uninstall it.
The app is gone. The code is not.
This is not a bug. It is how Shopify works. When an app is uninstalled, Shopify removes the app from your admin but does not touch your theme files. Every snippet, every stylesheet reference, every inline script the app injected — it all stays behind. Invisible to you, but very visible to Google PageSpeed Insights.
We have seen stores drop from a PageSpeed score of 95 to 60 after installing and uninstalling just three or four apps over the course of a year. That dead code loads on every single page view. It fires HTTP requests to servers that no longer respond. It blocks rendering while the browser waits for scripts that will never execute. Your customers do not notice it directly, but Google does — and your conversion rate quietly suffers.
The average Shopify store installs 6–8 apps. Stores that have been running for two or more years have often cycled through 15–20. That is a lot of dead code accumulating in your theme.
ThemeSweep and Cleanify Code both attempt to solve this problem. They scan your Shopify theme files for code left behind by uninstalled apps, flag it, and let you remove it. The goal is the same: a cleaner theme, faster page loads, better PageSpeed scores.
On the surface, they look similar. Both integrate with Shopify. Both scan Liquid, JavaScript, and CSS files. Both present you with a list of detected dead code and give you options to clean it up.
The difference is in how they decide what counts as "dead."
This is where things get important. Removing dead code sounds straightforward until you accidentally remove code from an app that is still installed and actively running on your store.
Cleanify Code uses pattern matching to identify app-related code in your theme. It maintains a database of known code signatures — patterns associated with popular Shopify apps — and flags anything that matches. This approach works well for detecting code. The problem is that it has no way of knowing whether the app that injected that code is still installed on your store.
Think about that for a moment. Cleanify Code sees a block of code in your theme that matches the signature for, say, a reviews app. It flags it as removable. But is the reviews app still installed? Cleanify Code does not check. It cannot tell the difference between code from an app you uninstalled six months ago and code from an app you are actively using right now.
Merchant reviews bear this out. The most common complaint about Cleanify Code is false positives — it flags code from apps that are still installed and working. If you follow its recommendations without carefully verifying each one, you can break live app functionality on your store. A reviews widget disappears. A currency converter stops working. A loyalty programme badge vanishes from product pages.
To be fair, Cleanify Code does warn users to review flagged items before removing them. But this puts the burden on the merchant to know exactly which code belongs to which app — which is the whole reason you are using a cleanup tool in the first place.
ThemeSweep takes a fundamentally different approach. Before flagging any code as dead, it cross-references your theme code against the list of apps currently installed on your store.
Here is the process:
This is not a subtle difference. It is the difference between a tool that says "this looks like app code, maybe remove it" and a tool that says "this code belongs to an app you uninstalled on 14 February — it is safe to remove."
| Feature | Cleanify Code | ThemeSweep |
|---|---|---|
| Detection method | Pattern matching only | Pattern matching + installed-app cross-reference |
| False positive risk | High — flags code from installed apps | Low — only flags code from uninstalled apps |
| Checks installed apps list | No | Yes — real-time via Shopify API |
| Scans Liquid files | Yes | Yes |
| Scans JS & CSS | Yes | Yes |
| Theme backup before cleanup | Varies by plan | Yes — automatic on all plans |
| One-click restore | Limited | Yes |
| Free plan | Yes — basic scanning | No — 7-day free trial |
| Starting paid price | $9.99/mo | $9.99/mo |
| Top-tier price | $99.99/mo | $39.99/mo |
Two other apps come up frequently in conversations about Shopify theme performance: Hyperspeed ($49/mo) and TinyIMG ($10–20/mo). Both are solid tools, but neither actually removes dead app code.
Hyperspeed focuses on compressing and minifying your existing theme assets — reducing file sizes, deferring scripts, and optimising load order. It makes your code load faster, but it does not remove code that should not be there in the first place. Think of it as making a cluttered room more efficiently cluttered.
TinyIMG handles image compression and basic SEO optimisation. Again, genuinely useful, but it operates on images and metadata, not on dead Liquid snippets or orphaned JavaScript files.
These tools are complementary to ThemeSweep or Cleanify Code, not alternatives. Clean up the dead code first, then optimise what remains.
We are not going to pretend Cleanify Code has no place. It does.
If you are a merchant who has only uninstalled one or two apps and you are confident you know which code belongs to which app, Cleanify Code's free plan gives you a basic scan at no cost. You can manually verify each flagged item and remove what you know is safe. For simple, low-risk cleanups, that might be all you need.
Cleanify Code also has the advantage of a free tier. If your budget is genuinely zero and you are willing to spend the time manually verifying every recommendation, it is better than doing nothing. Dead code sitting in your theme is worse than a tool with imperfect accuracy — provided you check its work.
ThemeSweep earns its price in situations where accuracy matters more than cost:
Dead code removal is one piece of the performance puzzle. After cleaning up orphaned app code, you might also want to look at:
ThemeSweep handles the cleanup. These tools handle the optimisation. Together, they cover the full performance stack.
Both ThemeSweep and Cleanify Code solve a real problem. Dead app code accumulates in Shopify themes and degrades performance in ways most merchants never notice until their PageSpeed score craters.
The fundamental difference is accuracy. Cleanify Code uses pattern matching to find app code in your theme. ThemeSweep uses pattern matching plus a real-time cross-reference against your installed apps list. That extra step is why ThemeSweep does not flag code from apps you are still using — and why Cleanify Code sometimes does.
If you want a free, basic scan and you are comfortable verifying every recommendation manually, Cleanify Code's free plan is a reasonable starting point. If you want confidence that the tool is only flagging genuinely dead code — especially across multiple stores or after years of app experimentation — ThemeSweep is built specifically for that.
ThemeSweep plans start at $9.99/mo with a 7-day free trial. No long-term contract. Try it on one store and compare the results against what you have been getting elsewhere. The scan takes minutes, and the difference in flagged items will tell you everything you need to know.
Whether you have questions about theme performance, need help choosing the right Shopify apps for your business, or want to explore custom development for your store, we are here to help. Get in touch and let us know what you are working on.
Related reading: How to Speed Test Your Shopify Theme (And What To Do When It Fails) · Shopify Theme Audit Tools Compared: Which One Is Worth Running · 5 Signs Your Shopify Theme Is Full of Dead App Code · The Hidden Cost of Uninstalling Shopify Apps · ThemeSweep.