diff --git a/src/main/kotlin/platform/mixin/handlers/mixinextras/WrapWithConditionHandler.kt b/src/main/kotlin/platform/mixin/handlers/mixinextras/WrapWithConditionHandler.kt
index 408fd7448..cb54352df 100644
--- a/src/main/kotlin/platform/mixin/handlers/mixinextras/WrapWithConditionHandler.kt
+++ b/src/main/kotlin/platform/mixin/handlers/mixinextras/WrapWithConditionHandler.kt
@@ -23,6 +23,7 @@ package com.demonwav.mcdev.platform.mixin.handlers.mixinextras
 import com.demonwav.mcdev.platform.mixin.inspection.injector.ParameterGroup
 import com.intellij.psi.PsiAnnotation
 import com.intellij.psi.PsiType
+import com.intellij.psi.PsiTypes
 import org.objectweb.asm.Type
 import org.objectweb.asm.tree.AbstractInsnNode
 import org.objectweb.asm.tree.ClassNode
@@ -44,6 +45,6 @@ class WrapWithConditionHandler : MixinExtrasInjectorAnnotationHandler() {
         insn: AbstractInsnNode
     ): Pair<ParameterGroup, PsiType>? {
         val params = getPsiParameters(insn, targetClass, annotation) ?: return null
-        return ParameterGroup(params) to PsiType.BOOLEAN
+        return ParameterGroup(params) to PsiTypes.booleanType()
     }
 }
diff --git a/src/main/kotlin/platform/mixin/inspection/injector/InjectCouldBeOverwriteInspection.kt b/src/main/kotlin/platform/mixin/inspection/injector/InjectCouldBeOverwriteInspection.kt
index 9d96a33dc..e0ff25791 100644
--- a/src/main/kotlin/platform/mixin/inspection/injector/InjectCouldBeOverwriteInspection.kt
+++ b/src/main/kotlin/platform/mixin/inspection/injector/InjectCouldBeOverwriteInspection.kt
@@ -72,7 +72,7 @@ import com.intellij.psi.PsiMethodCallExpression
 import com.intellij.psi.PsiParameter
 import com.intellij.psi.PsiParameterList
 import com.intellij.psi.PsiReturnStatement
-import com.intellij.psi.PsiType
+import com.intellij.psi.PsiTypes
 import com.intellij.psi.codeStyle.VariableKind
 import com.intellij.psi.impl.light.LightParameter
 import com.intellij.psi.search.LocalSearchScope
@@ -149,7 +149,7 @@ class InjectCouldBeOverwriteInspection : MixinInspection() {
         memState.applyCondition(ciVar.eq(stableCiVar))
         val isCancelledVar = PlainDescriptor.createVariableValue(
             factory,
-            LightParameter("isCancelled", PsiType.BOOLEAN, methodBody)
+            LightParameter("isCancelled", PsiTypes.booleanType(), methodBody)
         )
         memState.setVarValue(isCancelledVar, falseValue)
 
diff --git a/src/main/kotlin/platform/mixin/util/Mixin.kt b/src/main/kotlin/platform/mixin/util/Mixin.kt
index fab55e079..2b522a7b5 100644
--- a/src/main/kotlin/platform/mixin/util/Mixin.kt
+++ b/src/main/kotlin/platform/mixin/util/Mixin.kt
@@ -44,6 +44,7 @@ import com.intellij.psi.PsiMethod
 import com.intellij.psi.PsiParameter
 import com.intellij.psi.PsiPrimitiveType
 import com.intellij.psi.PsiType
+import com.intellij.psi.PsiTypes
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.util.InheritanceUtil
 import com.intellij.psi.util.PsiModificationTracker
@@ -165,7 +166,7 @@ fun isAssignable(left: PsiType, right: PsiType, allowPrimitiveConversion: Boolea
         left is PsiArrayType -> right is PsiArrayType && isAssignable(left.componentType, right.componentType)
         else -> {
             if (left !is PsiClassType || right !is PsiClassType) {
-                if (right == PsiType.NULL && left !is PsiPrimitiveType) {
+                if (right == PsiTypes.nullType() && left !is PsiPrimitiveType) {
                     return true
                 }
                 if (!allowPrimitiveConversion && (left is PsiPrimitiveType || right is PsiPrimitiveType)) {