- the SDK sends

If-None-Match

for feature requests

- when the server returns

304

,

NetworkClient

turns it into an error: “Not Modified - Use cached data”

-

FeaturesViewModel

then goes through the failure path and falls back to cached features

-

GrowthBookSDK

reports this via

refreshHandler(.failedToFetchData)

So from the app side, feature delivery is effectively OK because cached features are reused, but the refresh is still reported as an error.

This causes false-positive error analytics and can also trigger unnecessary retry logic. Also, the original HTTP 304 seems to get collapsed into generic

.failedToFetchData

, so integrators can’t distinguish “not modified, cache still valid” from a real network failure.

Relevant code:

- NetworkClient: https://github.com/growthbook/growthbook-swift/blob/1.0.97/Sources/CommonMain/Network/NetworkClient.swift#L54-L105

- FeaturesViewModel: https://github.com/growthbook/growthbook-swift/blob/1.0.97/Sources/CommonMain/Features/FeaturesViewModel.swift#L97-L109

- GrowthBookSDK: https://github.com/growthbook/growthbook-swift/blob/1.0.97/Sources/CommonMain/GrowthBookSDK.swift#L525-L528

failedToFetchData