diff --git a/docs/scarpet/api/BlocksAndWorldAccess.md b/docs/scarpet/api/BlocksAndWorldAccess.md
index 14d2792d..6f02cc1b 100644
--- a/docs/scarpet/api/BlocksAndWorldAccess.md
+++ b/docs/scarpet/api/BlocksAndWorldAccess.md
@@ -72,7 +72,10 @@ set(x,y,z,'hopper', l('facing', 'north'), nbt('{Items:[{Slot:1b,id:"minecraft:sl
 
 ### `without_updates(expr)`
 
-Evaluates subexpression without causing updates when blocks change in the world
+Evaluates subexpression without causing updates when blocks change in the world.
+
+For synchronization sake, as well as from the fact that suppressed update can only happen within a tick,
+the call to the `expr` is docked on the main server task.
 
 Consider following scenario: We would like to generate a bunch of terrain in a flat world following a perlin noise 
 generator. The following code causes a cascading effect as blocks placed on chunk borders will cause other chunks to get 
diff --git a/src/main/java/carpet/script/CarpetExpression.java b/src/main/java/carpet/script/CarpetExpression.java
index 85e1573a..b6b01917 100644
--- a/src/main/java/carpet/script/CarpetExpression.java
+++ b/src/main/java/carpet/script/CarpetExpression.java
@@ -759,16 +759,21 @@ public class CarpetExpression
         this.expr.addLazyFunction("without_updates", 1, (c, t, lv) ->
         {
             boolean previous = CarpetSettings.impendingFillSkipUpdates;
-            try
+            if (previous) return lv.get(0);
+            Value [] result = new Value[]{Value.NULL};
+            ((CarpetContext)c).s.getMinecraftServer().submitAndJoin( () ->
             {
-                CarpetSettings.impendingFillSkipUpdates = true;
-                Value ret = lv.get(0).evalValue(c, t);
-                return (cc, tt) -> ret;
-            }
-            finally
-            {
-                CarpetSettings.impendingFillSkipUpdates = previous;
-            }
+                try
+                {
+                    CarpetSettings.impendingFillSkipUpdates = true;
+                    result[0] = lv.get(0).evalValue(c, t);
+                }
+                finally
+                {
+                    CarpetSettings.impendingFillSkipUpdates = previous;
+                }
+            });
+            return (cc, tt) -> result[0];
         });
 
         this.expr.addLazyFunction("set", -1, (c, t, lv) ->
@@ -3249,18 +3254,13 @@ public class CarpetExpression
                             throw new InternalExpressionException("Incorrect dimension string: "+dimString);
                         innerSource = outerSource.withWorld(outerSource.getMinecraftServer().getWorld(dim));
                 }
-            }
-            try
-            {
-                ((CarpetContext) c).s = innerSource;
-                Value retval = lv.get(1).evalValue(c);
-                return (cc, tt) -> retval;
-            }
-            finally
-            {
-                ((CarpetContext) c).s = outerSource;
-            }
-
+            };
+            if (innerSource.getWorld() == outerSource.getWorld()) return lv.get(1);
+            Context newCtx = c.recreate();
+            ((CarpetContext) newCtx).s = innerSource;
+            newCtx.variables = c.variables;
+            Value retval = lv.get(1).evalValue(newCtx);
+            return (cc, tt) -> retval;
         });
 
         this.expr.addLazyFunction("plop", 4, (c, t, lv) ->{
diff --git a/src/main/java/carpet/script/Context.java b/src/main/java/carpet/script/Context.java
index 8d1cd434..50548fb3 100644
--- a/src/main/java/carpet/script/Context.java
+++ b/src/main/java/carpet/script/Context.java
@@ -20,7 +20,7 @@ public class Context
     public static final int LVALUE = 9;
     public static final int MAPDEF = 10;
 
-    public final Map<String, LazyValue> variables = new HashMap<>();
+    public Map<String, LazyValue> variables = new HashMap<>();
 
     public final ScriptHost host;
 
diff --git a/src/main/resources/fabric.mod.json b/src/main/resources/fabric.mod.json
index e79cb4e9..7506e9c1 100644
--- a/src/main/resources/fabric.mod.json
+++ b/src/main/resources/fabric.mod.json
@@ -13,7 +13,7 @@
     "sources": "https://github.com/gnembon/fabric-carpet"
   },
 
-  "license": "GNU LGPL V3",
+  "license": "MIT",
   "icon": "assets/carpet/icon.png",
 
   "environment": "*",