@caprail/config-runtime

Shared helpers for config lifecycle in long-lived Caprail runtimes.

What it owns

• stable in-memory config runtime objects
• optional file-fingerprint-based reload behavior
• fail-closed caching for reload failures until the source changes again

What it does not own

• parsing or validating any specific config format
• resolving default config paths
• transport-specific error-to-protocol mapping

Those remain in guard or transport packages.

API

createConfigRuntime({ config, configPath })

Create a simple runtime that always returns the same active config.

createReloadableConfigRuntime({ config, configPath, reloadConfig })

Create a runtime that reloads when the file fingerprint changes. reloadConfig({ config, configPath }) must return either:

• { ok: true, config, configPath? }
• { ok: false, error }

On reload failure, the runtime returns a fail-closed error until the fingerprint changes again.