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25 proposals
Order description:
We are looking for an experienced frontend developer/OpenCart specialist to optimize the loading speed of the website (categories and product cards) according to Google Core Web Vitals requirements.
About the project:
* CMS: OpenCart.
* Specifics: The site operates in catalog mode (no cart or checkout).
* Volume: 2900 items.
* Server part: Already optimized (runs on OpenLiteSpeed).
* Stack: Work is done exclusively with the template code, modifiers, and frontend. No work with the database.
What needs to be done (Technical task):
1. Delayed loading of scripts (Delay JS):
* Problem: Third-party analytics scripts (GTM, Google Tag) block the main thread on mobile devices for about 4.3 seconds.
* Task: Set up delayed execution of these scripts. The scripts should activate strictly on the first user action (first scroll, tap on the screen, or mouse movement).
* Important: Data collection, analytics, and ad functionality must remain intact.
2. Fixing the CLS metric (Layout Stability):
* Problem: The page "jumps" and shifts during image loading.
* Task: In the style files or theme template, hardcode the HTML attributes width and height for all product images in the catalog (listings) and product cards.
* Goal: Reserve space for images in the DOM tree until they are actually loaded to prevent content shifting. Ensure that responsiveness (CSS) is not broken.
3. Optimization of the critical path (LCP):
* Task: Add the fetchpriority="high" tag for the main product image on the first screen. This will instruct the browser to load the main product photo as a priority.
Requirements for the performer and acceptance conditions:
1. No unnecessary modules: Work is performed with clean code/modifiers, without installing additional third-party or paid optimization plugins.
2. Security and layout: You are fully responsible for the layout. After making changes, the visual display of the site on mobile and PC, as well as functionality (filters, photo switching in the gallery, menu) must remain unchanged.
3. Criteria for job submission (DoD): Provide a screenshot and a link to a live test report from Google PageSpeed Insights (for the mobile version). The performance score must be no lower than 75 points, and the CLS metric must be no more than 0.1 (in the green zone).
Changes must be made strictly through modifiers (OCMOD) or a copy of the theme to avoid overwriting core updates.
In your response, please indicate:
1. Have you had experience configuring Delay JS specifically for GTM on OpenCart?
2. The estimated time for task completion.
3. The cost of the work.
