FA-74239 / Feature flag rollout bucketing / Member archive

Flag override resolution: An invalid layer short-circuits to the default · case 04

A malformed environment value hides a valid remote value.

Member previewVariant 4 · 3 implementations · 8 checks per implementation

Case contract

Layers in precedence order: env var FLAG_<KEY uppercased with "-" -> "_">, local overrides[key], remote[key], then the default. A layer is used only if its value is valid for the default's type, else the next layer is tried. Non-env values must have exactly the default's type (bool is not int). Env strings: bool defaults accept "true"/"false" case-insensitively; int defaults accept digits with an optional leading "-"; str defaults accept any string. Return [value, source].

Why this case matters

Local and environment overrides are how operators pin flags during incidents; precedence must be exact.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
invalid env value falls through to remote	`[0, "default"]`	`[5, "remote"]`	Failed

MEMBER ARCHIVE

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This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

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