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README.md

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+# MixinConstraints
+
+A library to enable/disable mixins using annotations.
+Annotations can be applied to mixin classes to toggle the whole mixin, or individual fields/methods for more precision.
+
+# Installing
+
+MixinConstraints is available through Maven Central
+The library currently only supports Fabric
+
+__Gradle__
+```groovy
+dependencies {
+    include(implementation("com.moulberry:mixinconstraints:1.0.0"))
+}
+```
+
+Next, you will need to bootstrap the library to affect your mixins.
+
+The easiest way is using the built-in Mixin Plugin by adding the following to your modid.mixins.json:
+```json
+{
+    "plugin": "com.moulberry.mixinconstraints.ConstraintsMixinPlugin",
+}
+```
+
+If you already have your own mixin plugin, you can use the [ConstraintsMixinPlugin](https://github.com/Moulberry/MixinConstraints/blob/master/src/main/java/com/moulberry/mixinconstraints/ConstraintsMixinPlugin.java) class as a reference to add support.
+
+# Using the library
+
+The library provides 4 annotations
+- @IfModLoaded (checks if a mod is loaded)
+- @IfModAbsent (checks if a mod is absent)
+- @IfMinecraftVersion (checks if the Minecraft version matches a range)
+- @IfDevEnvironment (checks if the game is running inside a development environment)
+
+These annotations can be applied to classes to control whether the whole mixin is applied
+
+For example, the following mixin will only be applied if sodium or embeddium is present
+```java
+@IfModLoaded(value = "sodium", aliases = {"embeddium"})
+@Mixin(BlockOcclusionCache.class)
+public class MixinSodiumBlockOcclusionCache {
+   ...
+}
+```
+
+Additionally, the annotations can also be applied to individual fields/methods
+
+For example, the following mixin will inject only one of the two methods depending on whether the mod is in a dev environment
+```java
+@Mixin(Minecraft.class)
+public class MixinMinecraft {
+    @IfDevEnvironment
+    @Inject(at = @At("HEAD"), method = "run")
+    private void runDev(CallbackInfo info) {
+        System.out.println("Hello from a dev environment!");
+    }
+
+    @IfDevEnvironment(negate = true)
+    @Inject(at = @At("HEAD"), method = "run")
+    private void runProd(CallbackInfo info) {
+        System.out.println("Hello from production!");
+    }
+}
+```
+
+# License
+The library is available under the MIT license.