Laravel configuration cache causing env() helper to return null in production

Laravel's configuration caching feature stores all values loaded from .env into a plain PHP array at cache time. This documented behavior, present across recent versions including 6.x through 10.x, means any subsequent env() call outside the configuration loading phase returns null once the configuration cache is active. Local development often runs without this cache, so env() appears to work normally, while production deployments that include caching as part of their pipeline expose the discrepancy.

The core tension is that the framework intentionally replaces env() calls with literal values during caching, yet the env() helper remains available in application code. This creates an unresolved decision about where the boundary lies between configuration definition and runtime consumption when the cache is active.

If an application relies on environment variables for feature flags or service credentials outside the config/ directory, is the expectation that all such access must be refactored through config() before caching is enabled? Are there documented exceptions where env() remains reliable after caching, or is the null return absolute for all non-configuration contexts? How should version-specific differences in cache serialization affect the decision to audit env() usage prior to deploying a cached configuration?