Custom Shopify theme or template: how to decide
What changes between adapting an existing theme and building your own, and what to check before choosing for your Shopify store.
Read articlePrestaShop cache problems: diagnosis and solutions
Identify which cache layer serves the wrong response and test a lasting correction without relying on repeated manual cache clearing.
A PrestaShop cache problem often appears as a change that does not show, an old page design or a different response for different visitors. The solution starts with identifying which layer serves the wrong version. Caching may exist in PrestaShop, a module, the server, a CDN and the browser.
Clearing everything may remove the symptom briefly, but it does not explain why it returns. Before changing settings, record the case: URL, time, expected change and reproduction conditions. Work on a test copy if you are modifying modules or the theme.
What each layer stores
| Layer | What it may store | A diagnostic clue |
|---|---|---|
| Browser | Previously downloaded assets and responses. | The fault differs between profiles or devices. |
| CDN or proxy | Assets and, depending on configuration, complete pages. | Different visitors receive the same old version. |
| Server or module | Generated content or results of repeated work. | The old response persists after clearing the browser. |
| PrestaShop and templates | Compilation and content related to the application. | A template change does not appear as expected. |
This table provides direction, but does not replace checking the actual configuration. A provider may combine layers and add rules based on cookies, language, currency or user type.
First check that the change actually exists
Verify that the product, price or file was saved in the correct environment. If you use multistore, confirm the store context. If an ERP or module overwrites the value again, synchronisation rather than caching may be responsible.
For theme changes, check that the published file belongs to the active theme. For static assets, inspect the URL received by the browser and whether its version changed. Do not conclude that caching is broken before proving that the origin serves the new content.
Review PrestaShop performance settings
The PrestaShop 8 performance documentation explains compilation, caching and debugging settings. Use the documentation matching your version and installed modules: the interface and behaviour may vary.
Use the admin controls before deleting directories yourself. If files must be changed, identify and back them up, and confirm they belong to the correct environment. Do not delete whole installation folders by following a generic recipe.
Design changes that do not appear
Compare the document response with the CSS and JavaScript downloaded. If the HTML is new but the styles are old, focus on those resources and their versioning. If the HTML itself contains the previous component, investigate the layers generating or storing the page.
Disable one optimisation at a time in testing. If combining or minifying assets causes the fault, identify the affected file or dependency. Leaving every optimisation disabled can conceal the problem while making loading slower.
Prices, stock and session content
Check the same case without signing in and with an account that has different terms. Review language, currency and customer group too. An incorrect price may come from a commercial rule, a pending update or a cache key that does not distinguish the necessary conditions.
The cart, checkout and personal areas need particular care. If another session's data appears, limit exposure and investigate the storage rule. A fast page displaying incorrect information is not a valid optimisation.
How to test the solution
- Reproduce the case using the original URL and conditions.
- Confirm the content saved at the origin.
- Clear or adjust one identified layer.
- Check a new visitor, an existing session and mobile.
- Test affected customer groups, languages or currencies.
- Complete the buying journey if prices or sessions are involved.
- Check that later changes appear without repeating a manual clear.
The final test matters. If every update requires several caches to be cleared manually, an invalidation rule or clear publishing process is missing. Documenting that rule avoids turning maintenance into a sequence of emergencies.
When to request a wider review
If caching faults recur alongside module errors, server problems or synchronisations that are difficult to trace, review the architecture and its owners. The cache may amplify an incident originating elsewhere.
If maintenance is making you consider a platform change, consultancy on Shopify's fit can clarify the dependencies. There is no need to blame every issue on PrestaShop or assume migration will remove the need for testing.
Further reading for your store
- A broader diagnosis of PrestaShop problems
- PrestaShop compared with Shopify
- Investigating a slow website
Sources and review
Editorial review: the Migraciones.io team · 30 October 2026. Features, plans and availability are checked against the linked sources.