One Shopify change, decided before it was written.
A shop owner asks for a small thing on the product page. Here is the whole answer, in the order it happened, and how to do the next one yourself.
This example uses Dawn. Your theme and store have not been accessed. The workflow would be adapted to your chosen theme.
Four steps, about five minutes, nothing to install.
The request
Said the way an owner says it, not the way a developer writes a ticket.
On the product page, under the Add to cart button, I want a short line of reassurance. One sentence, and I want to be able to change the words myself. It should only appear on the products it applies to, not on all of them.
The decision, before the code
Nothing gets written until someone has said whether it needs writing at all.
The first thing asked of Claude, word for word
Inspect the existing theme first. Explain whether this can be done in the theme editor, which files would need changing, and why. Do not edit anything yet.
Most of it needed no code at all: the theme already has a text block you drag under the buy button, and a second product template for the products that differ. Code buys one thing here, and it is named: making the rule automatic, so products added next year are covered too.
The change, and what the check refused
A stylesheet was named in the section before the file existed. The block would have reached customers unstyled, on every product page, until someone noticed.
git commit -m "product note block under the buy button" [error]: MissingAsset 'assets/component-product-note.css' does not exist Commit refused. Nothing was committed. exit code 1
That mistake was introduced on purpose, to exercise the check. The command, the rule, the exit code and the proof that nothing was committed are kept dated in the repository: the refusal, in full.
Doing it again, yourself
The point of the exercise is that the next one does not need me.
A variation to try: the same note on a different tag, in different words. Nothing in the code changes. You add the block again in the theme editor, type the tag, type the sentence. If that needs a developer, the block was built wrong. What to look at before it goes live, and how to undo any of it, is in the exercise.
Static illustration. Not a Shopify render.
Two verdicts, kept apart
Automated checks passed.
Shopify rendering and editor behaviour: not tested.
The check is a static analyser: it reads the theme files. It does not open a browser, a theme editor or a shop. Seeing the line sit right under the buy button is a preview on a development theme, and that is a different statement.
Repeat it in VS Code.
The repository is public. Reading the four steps needs nothing at all. Running them needs Node 22.12 or newer, VS Code and git, and only the preview step needs a store where a development theme can be created.
git clone https://github.com/fred1433/shopify-claude-code-starter.git cd shopify-claude-code-starter npm install npm run check
The last line reads the whole theme in about four seconds. Claude Code opened in that folder reads its instructions on its own, and the opening move on any request is the prompt in step two. Those four lines were run on a machine that had never seen the repository, and the transcript is kept with the rest.