Synthetic or deliverable? Know your test data.
Choose address fixtures that fit your test without copying customer information into development.
A realistic format is not a verified destination
Synthetic records are useful for layouts, validation, exports and demos. They may resemble real locations, but are not evidence of residency and do not guarantee delivery. Use a carrier sandbox or an authorized test destination for fulfillment integration tests.
Give each test a deliberate boundary
A component test may only need a long street string. A checkout flow needs coherent country and region fields. A delivery test needs verified provider fixtures. Choosing the smallest useful dataset makes failures easier to understand.
Keep personal information out of fixtures
Use synthetic names and example.com email addresses instead of copied customer profiles. Treat generated phone fields as test placeholders. fakeloc generates data locally so a normal browser session does not upload the generated profiles.
Save the seed with the test
A stable seed captures the fixture choice without hard-coding a large snapshot. Pin the generator version too: intentional catalog changes can change output even when a seed stays the same.