FlatRedBall

Glue↔running-game live edit (drag/resize/tweak a live game, changes flow back to Glue). Triggers: GlueControl, GameConnectionManager, CommandReceiver, VariableAssignmentLogic, EmbeddedCodeManager, ActivityEditMode, edit mode.

The .achx animation file format and its save/runtime split. Triggers: .achx, AnimationChainListSave, AnimationChainSave, AnimationFrameSave, ToAnimationChainList, FromXElement.

Creates and updates skill files (.claude/skills/*/SKILL.md). Triggers: creating/updating a skill, documenting a subsystem for agent context.

Use when adding, modifying, or reasoning about Gluj/Glux file format versions, the GluxVersions enum, FileVersion checks, or anything that gates behavior on the version of a loaded Glue project.

Use when working on Glue's Gum code generation — adding/removing/version-gating generated properties on Gum standard runtime types (NineSlice, Text, Container, Sprite, etc.), or debugging "why is/isn't this Gum variable being generated."

This skill should be used when the user asks to refactor code, do a refactor pass, clean up code, extract a class or service, inject a dependency, or make incremental improvements to existing code structure.