diff --git a/src/loaders/forge/raw-forge-metadata.ts b/src/loaders/forge/raw-forge-metadata.ts
new file mode 100644
index 0000000..37114a3
--- /dev/null
+++ b/src/loaders/forge/raw-forge-metadata.ts
@@ -0,0 +1,105 @@
+import { ACTION_NAME } from "@/action";
+import { ForgeDependency } from "./forge-dependency";
+import { ForgeMod } from "./forge-mod";
+import { ForgeMetadataCustomPayload } from "./forge-metadata-custom-payload";
+
+// TODO: Remove the deprecated stuff in v4.0.
+
+/**
+ * The metadata file for a Forge mod.
+ */
+export interface RawForgeMetadata {
+    /**
+     * The language loader for the mod.
+     *
+     * Used to specify an alternative language for the mod, such as Kotlin, if one exists.
+     * The Forge-provided Java loader is `javafml`.
+     */
+    modLoader: string;
+
+    /**
+     * The acceptable version range of the language loader, expressed as a Maven version spec.
+     *
+     * For the Forge-provided Java loader, the version is the major version of the Forge version.
+     */
+    loaderVersion: string;
+
+    /**
+     * The license for the mod(s) in this JAR.
+     *
+     * This string may be any valid string, but it is suggested to set the value to be the
+     * name of your license, and/or a link to that license.
+     */
+    license: string;
+
+    /**
+     * Whether to display this mod's resources as a separate option in the resource pack menu.
+     *
+     * If disabled, the mod's resources will be rolled into the "Mod resources" pack.
+     *
+     * Defaults to `false`.
+     */
+    showAsResourcePack?: boolean;
+
+    /**
+     * A table of custom substitution properties.
+     *
+     * This is used by `StringSubstitutor` to replace values, using `${file.*}`.
+     */
+    properties?: Record<string, unknown>;
+
+    /**
+     * A URL for an issues tracker.
+     *
+     * This should never be a blank string, as that will cause an error.
+     */
+    issueTrackerURL?: string;
+
+    /**
+     * The mod properties, with a section for each mod.
+     */
+    mods?: ForgeMod[];
+
+    /**
+     * Dependency configurations, with a section for each mod's dependencies.
+     */
+    dependencies?: Record<string, ForgeDependency[]>;
+
+    /**
+     * Custom action payload.
+     */
+    [ACTION_NAME]?: ForgeMetadataCustomPayload;
+
+    /**
+     * Custom action payload (legacy).
+     *
+     * @deprecated
+     *
+     * Use [{@link ACTION_NAME}] instead.
+     */
+    projects?: ForgeMetadataCustomPayload;
+
+    /**
+     * Custom action payload (legacy).
+     *
+     * @deprecated
+     *
+     * Use [{@link ACTION_NAME}] instead.
+     */
+    custom?: {
+        /**
+         * Custom action payload.
+         */
+        [ACTION_NAME]?: ForgeMetadataCustomPayload;
+
+        /**
+         * Custom action payload.
+         */
+        projects?: ForgeMetadataCustomPayload;
+    };
+}
+
+/**
+ * Name of the `mods.toml` file, that contains raw Forge metadata.
+ */
+export const MODS_TOML = "META-INF/mods.toml";