Preloading Tricks

Overview

Preloading Tricks is a developer-only mod that enables advanced operations during the very early stage of the mod loader. It provides early hooks, Java Instrumentation-based class transformation, and SPI-driven callbacks for loader extension.

Supported environments:

* NeoForge – 1.20.1, 1.21+ * NeoForge – 1.20.1 * NeoForge – 1.20.6, 1.21+

You can test on more versions since it depends on the loader version instead of the Minecraft version.

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Features

* Early loader entrypoint via `PreloadingEntrypoint` (SPI-based)

* Register callbacks using `PreloadingTricksCallbacks` events: * `SETUP_LANGUAGE_ADAPTER` – early language adapter setup stage * `COLLECT_MOD_CANDIDATES` – dynamically add mod candidate paths before discovery * `SETUP_MODS` – modify mod list (add/remove/query via `ModManager` API) * Instrumentation-powered `ClassTransform` Can transform already-loaded classes, including Java core and classloader classes. Configure via `MANIFEST.MF` on all platforms (see below).

* Forge variant detection (Forge-like only) * Access `ForgeVariants` to detect specific Forge/NeoForge versions at runtime

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Usage (Gradle)

Add the Maven repository and dependency to your build:

Kotlin DSL:

```kotlin repositories { maven("https://raw.githubusercontent.com/settingdust/maven/main/repository/") }

dependencies { // Recommended: use the base artifact (no classifier). // Gradle variant matching / cloche will resolve the correct platform artifact automatically. implementation("settingdust.preloading_tricks:PreloadingTricks:VERSION")

// Optional: pin to a specific classifier when you want to avoid accidentally using APIs // from other platforms. // implementation("settingdust.preloading_tricks:PreloadingTricks:VERSION:fabric") // implementation("settingdust.preloading_tricks:PreloadingTricks:VERSION:forge-service") // implementation("settingdust.preloading_tricks:PreloadingTricks:VERSION:neoforge-modlauncher") // implementation("settingdust.preloading_tricks:PreloadingTricks:VERSION:neoforge-fancy-mod-loader") } ```

Replace `VERSION` with the latest release (e.g. `3.5.9`).

If you are using cloche, the corresponding variant is selected automatically based on loader/minecraft attributes.

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ClassTransform Configuration

For all platforms, add the following attribute to your `MANIFEST.MF`:

``` ClassTransformConfig: xxxx.classtransform.json ```

Multiple configs can be specified as comma-separated values:

``` ClassTransformConfig: first.classtransform.json,second.classtransform.json ```

Example config (`xxxx.classtransform.json`):

```json { "package": "settingdust.preloading_tricks.neoforge.transformer", "transformers": [ "mod_setup_hook.FMLLoaderTransformer" ] } ```

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Forge Variant Detection (Forge-like only)

Allows a mod to load only on a specific Forge-like loader variant. This enables bundling both LexForge and NeoForge JARs together via jar-in-jar in a single mod file.

Configuration:

Specify your mod's target variant in `MANIFEST.MF`: ``` ForgeVariant: LexForge ``` or ``` ForgeVariant: NeoForge ```

Mods with a `ForgeVariant` specified will only load when running on the matching loader variant, allowing safe coexistence of variant-specific implementations.

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For developers who need to reach into the earliest moments of Minecraft’s loading process.