Handle Version Upgrades

When you release a new version of your package, users upgrading from older versions may need data migrations — transforming config formats, moving files, or updating store schemas. The version graph defines the migration path between versions.

Solution

Define a VersionGraph with a current version and an array of other (previous) versions. Each version has up and down migration functions. Use IMPOSSIBLE for directions that can’t be migrated. The up migration transforms old config, moves files, or runs storeJson.merge(effects, {}) to apply new zod defaults. Only versions that users might be upgrading from need entries in the other array.

Reference: Versions · File Models

Examples

See startos/versions/ in: bitcoin-core, cln, lnd, monerod, nextcloud, simplex, tor, synapse