diff --git a/src/platforms/curseforge/curseforge-game-version-union.ts b/src/platforms/curseforge/curseforge-game-version-union.ts
new file mode 100644
index 0000000..f42d52d
--- /dev/null
+++ b/src/platforms/curseforge/curseforge-game-version-union.ts
@@ -0,0 +1,21 @@
+import { JavaVersion } from "@/utils/java";
+
+/**
+ * Represents a union of entities CurseForge treats as "game versions".
+ */
+export interface CurseForgeGameVersionUnion {
+    /**
+     * An array of supported game versions for this project version.
+     */
+    game_versions?: string[];
+
+    /**
+     * An array of supported java versions for this project version.
+     */
+    java_versions?: (string | JavaVersion)[];
+
+    /**
+     * The mod loaders that this version supports.
+     */
+    loaders?: string[];
+}