Plan a controlled Paymenter extension installation

Installing an extension on a billing platform deserves a short change plan. The package may add migrations, routes, admin permissions or integration hooks, and a successful upload does not demonstrate that every workflow still works.

Start with the package's actual README. An extension's folder name is not enough to determine whether it belongs under Servers, Gateways or Others.

Record the starting point

Note the Paymenter, PHP and theme versions. Identify any existing custom changes in files mentioned by the installer. Save a current backup of the database and relevant application files, and confirm who can restore it.

Do not rely on replacing an entire core file with an older copy from a package. Follow the documented integration procedure and inspect any conflicts with local changes.

Use a test installation when practical

Match the important production versions and use payment-provider test credentials there. Test ordinary checkout, an unpaid invoice, the new extension flow and an unauthorized account. A feature that works for an administrator may still fail for a customer with fewer permissions.

For Combine Invoices, include eligibility failures and the undo boundary in those checks, not just the successful creation of a replacement invoice.

Apply the change deliberately

Choose a quiet window and have someone responsible for observing errors. Run only the documented migrations and cache/worker steps. Preserve the original installer output privately if it will help explain a failure.

Do not use a blanket cache flush as a substitute for knowing which component needs refreshing.

Validate the result

Check desktop and mobile pages, a normal invoice, and the new feature's permissions. Confirm that existing services and invoices retain their amounts. If a check fails, compare the observed result with the change plan before making unrelated edits.

The Combine Invoices listing includes the package requirements. Its README remains the source for the exact installation steps.