### Fixed
- **Spigot compatibility** – `ItemStack` data is now stored as a Base64-encoded byte stream (`item-data` key) via `BukkitObjectOutputStream` instead of YAML-native serialization. This eliminates the `[ERROR] Material cannot be null` log entries that appeared during startup when loading YAML files written by a Paper 1.21+ server on a Spigot server. Existing files are migrated to the new format automatically on the next save cycle; the old `item` key is still read as a fallback during the transition.
- **Smoke test coverage** – Added `YamlAuctionStorageSmokeTest` (8 tests) and a dedicated `spigot-smoke.yml` GitHub Actions workflow to guard this code path in CI.
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Optional dependencies
PlaceholderAPI
Any compatible version
DiscordSRV
Any compatible version
Teams API
Any compatible version
EzShops
Any compatible version
Developer information
Projects on Modrinth are automatically available through a Maven repository for use with JVM build tools such as Gradle.
maven { name = "Modrinth"; url = "https://api.modrinth.com/maven" }
