Java services often run the code paths where feature flags matter most: checkout, billing, authorization, data processing, and worker jobs.
A Java feature flag SDK should keep those decisions explicit. The application should know the flag key, the user or account identifier, and the fallback behavior before production traffic reaches the new path.
Create one client per service
Build the ReleaseAnchor client once during application startup and inject it into the code that needs rollout decisions.
ReleaseAnchorClient client = ReleaseAnchorClient.builder()
.apiKey(System.getenv("RELEASE_ANCHOR_KEY"))
.build();Evaluate with a safe default
For backend flows, the safe default is usually the stable behavior that existed before the release.
boolean enabled = client.evaluate(
"new-checkout",
user.getId(),
false
);
return enabled ? newCheckout(order) : legacyCheckout(order);Scope keys by environment
A staging key should not evaluate production flags. Keep API keys environment-scoped and rotate them when service ownership changes.
Use segments for account-level releases
Many B2B rollouts should be stable at the account or tenant level. Use segments when a feature should be enabled for a named group of customers instead of a random percentage of users.
Related docs
Try ReleaseAnchor
Create a flag, connect an SDK, and ship your next rollout with a safe default.