I see v1 and v1-sandbox in the docs. Are these different APIs, or the same one with a flag?
I want to build against test data first and switch to live later without rewriting my integration.
Same API, same handlers, same validation, same response shape. The suffix picks the mode, not a different product.
Two things have to agree:
-sandbox (v1-sandbox, v2-sandbox, and so on)uk_test_If they disagree in either direction you get a 401. A live key on a sandbox path fails, and a test key on a live path fails. That is deliberate: the most expensive mistake here is moving real money while you believed you were testing.
Because there is exactly one schema and one serializer per endpoint, a sandbox response cannot drift from a live one. Only the values differ.
Going live is two edits: drop the suffix from the path, swap uk_test_ for your live key. Nothing else in your code changes.
Sandbox also never calls a real gateway. It runs our own simulator, so no request leaves our network and no real money can move through it.