diff --git a/effects.v b/effects.v
index 0896a74..300b52e 100644
--- a/effects.v
+++ b/effects.v
@@ -14,6 +14,8 @@ fn new_effect() &Effect {
 	e := &Effect{
 		//in_elem: null,
 		//out_elem: null,
+		in_elem: &Elem(0),
+		out_elem: &Elem(0),
 	}
 	return e
 }
diff --git a/elems.v b/elems.v
index 525a5e4..cb190dd 100644
--- a/elems.v
+++ b/elems.v
@@ -62,10 +62,13 @@ mut:
 }
 
 fn new_elem() &Elem {
+	/*
 	e := &Elem{
 		//when_crushed_effects: []Effect{},
 		//when_crushed_out_elems: []Elem{},
 		//generic_processor0: none,
 	}
+	*/
+	e := &Elem{}
 	return e
 }
diff --git a/generic_processor.v b/generic_processor.v
index b6bb962..33e4ba3 100644
--- a/generic_processor.v
+++ b/generic_processor.v
@@ -15,7 +15,7 @@ mut:
 }
 
 fn new_generic_crusher_processor() &GenericCrusherProcessor {
-	gcp := &GenericCrusherProcessor{}
+	mut gcp := &GenericCrusherProcessor{}
 	gcp.name = "generic_crusher_processor"
 	return gcp
 }
diff --git a/main.v b/main.v
index f0d1f28..a62278e 100644
--- a/main.v
+++ b/main.v
@@ -44,19 +44,20 @@ fn main() {
 	// Effects
 	//
 	
-	ef := new_effect()
+	mut ef := new_effect()
 	ef.name = "melt"
 	ef.in_elem = e2
 	ef.out_elem = e3
 	ef.cond_temp = 5000
 
-	println("ef: ${ef}")
+	// XXX bug: can't print recursive elems?
+	//println("ef: ${ef}")
 
 	//
 	// Objects
 	//
 
-	ob := new_object()
+	mut ob := new_object()
 	ob.name = "stone1"
 	ob.dim_x = 2
 	ob.dim_y = 2
@@ -68,13 +69,14 @@ fn main() {
 	ob.transform.pos_y = 10.0
 	ob.transform.rot_z = 45.0
 
-	println("ob: ${ob}")
+	// XXX
+	//println("ob: ${ob}")
 
 	//
 	// Processors
 	//
 
-	prc := new_processor()
+	mut prc := new_processor()
 	prc.name = "crushed_stone"
 	prc.in_elem = e4
 	prc.out_elem = e4
@@ -82,7 +84,8 @@ fn main() {
 	prc.req_electricity = true
 	prc.req_power = 1000
 
-	println("prc: ${prc}")
+	// XXX
+	//println("prc: ${prc}")
 
 	//
 	// Universal Processors?
@@ -96,7 +99,7 @@ fn main() {
 	prc2.process(ob)
 	*/
 
-	gcp := new_generic_crusher_processor()
+	mut gcp := new_generic_crusher_processor()
 	gcp.process(ob)
 
 	//e4.generic_processor0 = gcp
@@ -110,7 +113,7 @@ fn main() {
 	// World
 	//
 
-	w := new_world()
+	mut w := new_world()
 
 	b1 := Bit{
 		elem_type: .wood,
@@ -127,7 +130,7 @@ fn main() {
 	// Complex object
 	//
 
-	ob2 := new_object()
+	mut ob2 := new_object()
 	ob2.name = "pipe" // Reinforced-concrete pipe, a 3d object
 	ob2.elem = e_concrete
 
diff --git a/object.v b/object.v
index 36b09c2..3003177 100644
--- a/object.v
+++ b/object.v
@@ -30,6 +30,7 @@ mut:
 
 fn new_object() &Object {
 	o := &Object{
+		elem: &Elem(0),
 		transform: new_transform(),
 	}
 	return o
diff --git a/processor.v b/processor.v
index 5a35455..6f17af0 100644
--- a/processor.v
+++ b/processor.v
@@ -16,6 +16,9 @@ mut:
 }
 
 fn new_processor() &Processor {
-	p := &Processor{}
+	p := &Processor{
+		in_elem: &Elem(0),
+		out_elem: &Elem(0),
+	}
 	return p
 }
diff --git a/run.sh b/run.sh
new file mode 100755
index 0000000..5f24d56
--- /dev/null
+++ b/run.sh
@@ -0,0 +1,3 @@
+#!/bin/bash
+
+v run .