File

The file provider writes JSON lines to daily files under ./logs in the app working directory.

Config

Field	Type	Required	Default	Notes
provider	file	✅ Yes	—	Selects the file provider.
enabled	boolean	❌ No	true	Enables/disables logging globally.
serviceName	string	❌ No	—	Included in each JSON log line if set.
retentionDays	number	❌ No	—	If set, old daily files are deleted.

Output format

Each log line is a JSON object with fields like: timestamp, level, message, serviceName, context, stack.