Genuinely lightweight
- Opens fast and uses little memory.
- Frugal on the network: what has not changed since last time is not downloaded again.
- One copy of each mod on disk, shared between instances.
- Launching an instance with hundreds of mods only re-reads a jar that changed.
Instance performance check
It looks at the machine memory, what the game gets, the Java and the number of mods, and suggests — in buttons:
- The right memory.
- The official launcher's garbage collector, or ZGC on Java 23+ with 4 GB or more.
- Optimization mods compatible with the version and loader, only when nothing installed already does that.
While the game runs
- The instance stays "starting" until the game opens its window — a big pack spends minutes loading mods before showing anything.
- Closing the launcher with the game open does not lose the session; on reopening it finds the process again.
- Forge and NeoForge open faster and work offline.