diff --git a/compiler/src/prog8/compiler/astprocessing/TypecastsAdder.kt b/compiler/src/prog8/compiler/astprocessing/TypecastsAdder.kt
index 590a212b9..e92887577 100644
--- a/compiler/src/prog8/compiler/astprocessing/TypecastsAdder.kt
+++ b/compiler/src/prog8/compiler/astprocessing/TypecastsAdder.kt
@@ -25,7 +25,8 @@ class TypecastsAdder(val program: Program, val options: CompilationOptions, val
             if(valueDt isnot decl.datatype) {
 
                 if(decl.isArray && !options.strictBool) {
-                    tryConvertBooleanArrays(decl, declValue, parent)
+                    if(tryConvertBooleanArrays(decl, declValue, parent))
+                        return noModifications
                 }
 
                 if(valueDt.isInteger && decl.isArray) {
@@ -53,7 +54,7 @@ class TypecastsAdder(val program: Program, val options: CompilationOptions, val
         return noModifications
     }
 
-    private fun tryConvertBooleanArrays(decl: VarDecl, declValue: Expression, parent: Node) {
+    private fun tryConvertBooleanArrays(decl: VarDecl, declValue: Expression, parent: Node): Boolean {
         val valueNumber = declValue.constValue(program)
         val valueArray = declValue as? ArrayLiteral
         when (decl.datatype) {
@@ -61,6 +62,7 @@ class TypecastsAdder(val program: Program, val options: CompilationOptions, val
                 if(valueNumber!=null) {
                     decl.value = NumericLiteral.fromBoolean(valueNumber.number!=0.0, declValue.position)
                     decl.linkParents(parent)
+                    return true
                 } else if(valueArray!=null) {
                     val newArray = valueArray.value.map {
                         if(it.inferType(program).isBytes) {
@@ -71,12 +73,14 @@ class TypecastsAdder(val program: Program, val options: CompilationOptions, val
                     }
                     decl.value = ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_BOOL), newArray.toTypedArray(), valueArray.position)
                     decl.linkParents(parent)
+                    return true
                 }
             }
             DataType.ARRAY_B -> {
                 if(valueNumber!=null) {
                     decl.value = NumericLiteral(DataType.BYTE, if(valueNumber.asBooleanValue) 1.0 else 0.0, declValue.position)
                     decl.linkParents(parent)
+                    return true
                 } else if(valueArray!=null) {
                     val newArray = valueArray.value.map {
                         if(it.inferType(program).isBool) {
@@ -87,12 +91,14 @@ class TypecastsAdder(val program: Program, val options: CompilationOptions, val
                     }
                     decl.value = ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_B), newArray.toTypedArray(), valueArray.position)
                     decl.linkParents(parent)
+                    return true
                 }
             }
             DataType.ARRAY_UB -> {
                 if(valueNumber!=null) {
                     decl.value = NumericLiteral(DataType.UBYTE, if(valueNumber.asBooleanValue) 1.0 else 0.0, declValue.position)
                     decl.linkParents(parent)
+                    return true
                 } else if(valueArray!=null) {
                     val newArray = valueArray.value.map {
                         if(it.inferType(program).isBool) {
@@ -103,10 +109,12 @@ class TypecastsAdder(val program: Program, val options: CompilationOptions, val
                     }
                     decl.value = ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_UB), newArray.toTypedArray(), valueArray.position)
                     decl.linkParents(parent)
+                    return true
                 }
             }
             else -> { /* no casting possible */ }
         }
+        return false
     }
 
     override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
@@ -487,7 +495,6 @@ class TypecastsAdder(val program: Program, val options: CompilationOptions, val
         return noModifications
     }
 
-
     private fun addTypecastOrCastedValueModification(
         modifications: MutableList<IAstModification>,
         expressionToCast: Expression,
diff --git a/compiler/src/prog8/compiler/astprocessing/VariousCleanups.kt b/compiler/src/prog8/compiler/astprocessing/VariousCleanups.kt
index fc996cf5d..bfaa113dc 100644
--- a/compiler/src/prog8/compiler/astprocessing/VariousCleanups.kt
+++ b/compiler/src/prog8/compiler/astprocessing/VariousCleanups.kt
@@ -96,6 +96,17 @@ internal class VariousCleanups(val program: Program, val errors: IErrorReporter,
             // +X --> X
             return listOf(IAstModification.ReplaceNode(expr, expr.expression, parent))
         }
+
+        if(!options.strictBool && expr.operator=="not") {
+            if(expr.expression.inferType(program).isBytes) {
+                // not bytevalue --> bytevalue==0
+                val cmp = BinaryExpression(expr.expression, "==",
+                    NumericLiteral(expr.expression.inferType(program).getOr(DataType.UNDEFINED), 0.0, expr.expression.position),
+                    expr.expression.position)
+                return listOf(IAstModification.ReplaceNode(expr, cmp, parent))
+            }
+        }
+
         return noModifications
     }
 
diff --git a/docs/source/todo.rst b/docs/source/todo.rst
index 9ee94cf40..4a7410dd2 100644
--- a/docs/source/todo.rst
+++ b/docs/source/todo.rst
@@ -1,6 +1,11 @@
 TODO
 ====
 
+the not changed (master branch) Petaxian compiled with -nostrictbool is a lot smaller than the updated (boolean branch) compiled without.
+What is the difference!
+
+
+
 ===== ====== =======
 VM    6502   what
 ===== ====== =======