diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index c79ce649fc..fe38a3a925 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -40,20 +40,20 @@ In general, if you are using IntelliJ, you should be warned about platform incom
 
 
 #### Use `arc` collections and classes when possible.
-Instead of using `java.util.List`, `java.util.HashMap`, and other standard Java collections, use `Array`, `ObjectMap` and other equivalents from `arc.struct`.
+Instead of using `java.util.List`, `java.util.HashMap`, and other standard Java collections, use `Seq`, `ObjectMap` and other equivalents from `arc.struct`.
 Why? Because that's what the rest of the codebase uses, and the standard collections have a lot of cruft and usability issues associated with them.  
 In the rare case that concurrency is required, you may use the standard Java classes for that purpose (e.g. `CopyOnWriteArrayList`).  
 
 What you'll usually need to change:
 - `HashSet` -> `ObjectSet`
 - `HashMap` -> `ObjectMap`
-- `List` / `ArrayList` / `Stack` -> `Array`
+- `List` / `ArrayList` / `Stack` -> `Seq`
 - `java.util.Queue` -> `arc.struct.Queue`
 - *Many others*
 
 
 #### Avoid boxed types (Integer, Boolean)
-Never create variables or collections with boxed types `Array<Integer>` or `ObjectMap<Integer, ...>`. Use the collections specialized for this task, e.g. `IntArray` and `IntMap`.
+Never create variables or collections with boxed types `Seq<Integer>` or `ObjectMap<Integer, ...>`. Use the collections specialized for this task, e.g. `IntSeq` and `IntMap`.
 
 
 #### Do not allocate anything if possible.
diff --git a/core/src/mindustry/world/blocks/distribution/Conveyor.java b/core/src/mindustry/world/blocks/distribution/Conveyor.java
index f38b0d99f7..b0658fd02d 100644
--- a/core/src/mindustry/world/blocks/distribution/Conveyor.java
+++ b/core/src/mindustry/world/blocks/distribution/Conveyor.java
@@ -94,24 +94,24 @@ public class Conveyor extends Block implements Autotiler{
 
     public class ConveyorEntity extends Building{
         //parallel array data
-        Item[] ids = new Item[capacity];
-        float[] xs = new float[capacity];
-        float[] ys = new float[capacity];
+        public Item[] ids = new Item[capacity];
+        public float[] xs = new float[capacity];
+        public float[] ys = new float[capacity];
         //amount of items, always < capacity
-        int len = 0;
+        public int len = 0;
         //next entity
-        @Nullable Building next;
-        @Nullable ConveyorEntity nextc;
+        public @Nullable Building next;
+        public @Nullable ConveyorEntity nextc;
         //whether the next conveyor's rotation == tile rotation
-        boolean aligned;
+        public boolean aligned;
 
-        int lastInserted, mid;
-        float minitem = 1;
+        public int lastInserted, mid;
+        public float minitem = 1;
 
-        int blendbits, blending;
-        int blendsclx, blendscly;
+        public int blendbits, blending;
+        public int blendsclx, blendscly;
 
-        float clogHeat = 0f;
+        public float clogHeat = 0f;
 
         @Override
         public void draw(){
@@ -350,7 +350,7 @@ public class Conveyor extends Block implements Autotiler{
         }
 
 
-        final void add(int o){
+        public final void add(int o){
             for(int i = Math.max(o + 1, len); i > o; i--){
                 ids[i] = ids[i - 1];
                 xs[i] = xs[i - 1];
@@ -360,7 +360,7 @@ public class Conveyor extends Block implements Autotiler{
             len++;
         }
 
-        final void remove(int o){
+        public final void remove(int o){
             for(int i = o; i < len - 1; i++){
                 ids[i] = ids[i + 1];
                 xs[i] = xs[i + 1];
diff --git a/core/src/mindustry/world/blocks/distribution/ExtendingItemBridge.java b/core/src/mindustry/world/blocks/distribution/ExtendingItemBridge.java
index a4786217b3..a1ace75eb0 100644
--- a/core/src/mindustry/world/blocks/distribution/ExtendingItemBridge.java
+++ b/core/src/mindustry/world/blocks/distribution/ExtendingItemBridge.java
@@ -15,7 +15,7 @@ public class ExtendingItemBridge extends ItemBridge{
         super(name);
         hasItems = true;
     }
-    
+
     public class ExtendingItemBridgeEntity extends ItemBridgeEntity{
         @Override
         public void draw(){
diff --git a/core/src/mindustry/world/blocks/distribution/ItemBridge.java b/core/src/mindustry/world/blocks/distribution/ItemBridge.java
index 3491f5b3ea..9c926c3450 100644
--- a/core/src/mindustry/world/blocks/distribution/ItemBridge.java
+++ b/core/src/mindustry/world/blocks/distribution/ItemBridge.java
@@ -357,7 +357,7 @@ public class ItemBridge extends Block{
             return liquids.get(liquid) + amount < liquidCapacity && (liquids.current() == liquid || liquids.get(liquids.current()) < 0.2f);
         }
 
-        private boolean linked(Building source){
+        protected boolean linked(Building source){
             return source instanceof ItemBridgeEntity && linkValid(source.tile(), tile) && ((ItemBridgeEntity)source).link == pos();
         }
 
diff --git a/core/src/mindustry/world/blocks/distribution/Junction.java b/core/src/mindustry/world/blocks/distribution/Junction.java
index 4c497d1634..cf4d7012b0 100644
--- a/core/src/mindustry/world/blocks/distribution/Junction.java
+++ b/core/src/mindustry/world/blocks/distribution/Junction.java
@@ -27,7 +27,7 @@ public class Junction extends Block{
     }
 
     public class JunctionEntity extends Building{
-        DirectionalItemBuffer buffer = new DirectionalItemBuffer(capacity);
+        public DirectionalItemBuffer buffer = new DirectionalItemBuffer(capacity);
 
         @Override
         public int acceptStack(Item item, int amount, Teamc source){
diff --git a/core/src/mindustry/world/blocks/distribution/MassDriver.java b/core/src/mindustry/world/blocks/distribution/MassDriver.java
index b61f57f741..1248dab005 100644
--- a/core/src/mindustry/world/blocks/distribution/MassDriver.java
+++ b/core/src/mindustry/world/blocks/distribution/MassDriver.java
@@ -86,13 +86,13 @@ public class MassDriver extends Block{
     }
 
     public class MassDriverEntity extends Building{
-        int link = -1;
-        float rotation = 90;
-        float reload = 0f;
-        DriverState state = DriverState.idle;
-        OrderedSet<Tile> waitingShooters = new OrderedSet<>();
+        public int link = -1;
+        public float rotation = 90;
+        public float reload = 0f;
+        public DriverState state = DriverState.idle;
+        public OrderedSet<Tile> waitingShooters = new OrderedSet<>();
 
-        Tile currentShooter(){
+        public Tile currentShooter(){
             return waitingShooters.isEmpty() ? null : waitingShooters.first();
         }
 
@@ -322,7 +322,7 @@ public class MassDriver extends Block{
         }
     }
 
-    enum DriverState{
+    public enum DriverState{
         idle, //nothing is shooting at this mass driver and it does not have any target
         accepting, //currently getting shot at, unload items
         shooting,
diff --git a/core/src/mindustry/world/blocks/distribution/OverflowGate.java b/core/src/mindustry/world/blocks/distribution/OverflowGate.java
index 01462261f6..58103915be 100644
--- a/core/src/mindustry/world/blocks/distribution/OverflowGate.java
+++ b/core/src/mindustry/world/blocks/distribution/OverflowGate.java
@@ -31,9 +31,9 @@ public class OverflowGate extends Block{
     }
 
     public class OverflowGateEntity extends Building{
-        Item lastItem;
-        Tile lastInput;
-        float time;
+        public Item lastItem;
+        public Tile lastInput;
+        public float time;
 
         @Override
         public int acceptStack(Item item, int amount, Teamc source){
diff --git a/core/src/mindustry/world/blocks/distribution/PayloadConveyor.java b/core/src/mindustry/world/blocks/distribution/PayloadConveyor.java
index c19e53efb5..72dc5c7050 100644
--- a/core/src/mindustry/world/blocks/distribution/PayloadConveyor.java
+++ b/core/src/mindustry/world/blocks/distribution/PayloadConveyor.java
@@ -136,7 +136,7 @@ public class PayloadConveyor extends Block{
             super.draw();
         }
 
-        @Override 
+        @Override
         public void draw(){
             super.draw();
 
@@ -241,15 +241,14 @@ public class PayloadConveyor extends Block{
             }
         }
 
-        boolean blends(int direction){
+        protected boolean blends(int direction){
             if(direction == rotation){
                 return !blocked || next != null;
-            }else{
-                return PayloadAcceptor.blends(this, direction);
             }
+            return PayloadAcceptor.blends(this, direction);
         }
 
-        TextureRegion clipRegion(Rect bounds, Rect sprite, TextureRegion region){
+        protected TextureRegion clipRegion(Rect bounds, Rect sprite, TextureRegion region){
             Rect over = Tmp.r3;
 
             boolean overlaps = Intersector.intersectRectangles(bounds, sprite, over);
@@ -273,11 +272,11 @@ public class PayloadConveyor extends Block{
             return out;
         }
 
-        int curStep(){
+        public int curStep(){
             return (int)((Time.time()) / moveTime);
         }
 
-        float fract(){
+        public float fract(){
             return interp.apply(progress / moveTime);
         }
     }
diff --git a/core/src/mindustry/world/blocks/distribution/Router.java b/core/src/mindustry/world/blocks/distribution/Router.java
index 2c8c1012f1..15bd106169 100644
--- a/core/src/mindustry/world/blocks/distribution/Router.java
+++ b/core/src/mindustry/world/blocks/distribution/Router.java
@@ -20,9 +20,9 @@ public class Router extends Block{
     }
 
     public class RouterEntity extends Building{
-        Item lastItem;
-        Tile lastInput;
-        float time;
+        public Item lastItem;
+        public Tile lastInput;
+        public float time;
 
         @Override
         public void updateTile(){
@@ -70,7 +70,7 @@ public class Router extends Block{
             return result;
         }
 
-        Building getTileTarget(Item item, Tile from, boolean set){
+        public Building getTileTarget(Item item, Tile from, boolean set){
             int counter = rotation;
             for(int i = 0; i < proximity.size; i++){
                 Building other = proximity.get((i + counter) % proximity.size);
diff --git a/core/src/mindustry/world/blocks/distribution/Sorter.java b/core/src/mindustry/world/blocks/distribution/Sorter.java
index 5596a87fef..f080f67f8c 100644
--- a/core/src/mindustry/world/blocks/distribution/Sorter.java
+++ b/core/src/mindustry/world/blocks/distribution/Sorter.java
@@ -48,7 +48,7 @@ public class Sorter extends Block{
     }
 
     public class SorterEntity extends Building{
-        @Nullable Item sortItem;
+        public @Nullable Item sortItem;
 
         @Override
         public void configured(Player player, Object value){
@@ -86,12 +86,12 @@ public class Sorter extends Block{
             to.handleItem(this, item);
         }
 
-        boolean isSame(Building other){
-            //uncomment code below to prevent sorter/gate chaining
+        public boolean isSame(Building other){
+            // comment code below to allow sorter/gate chaining
             return other != null && (other.block() instanceof Sorter || other.block() instanceof OverflowGate);
         }
 
-        Building getTileTarget(Item item, Building source, boolean flip){
+        public Building getTileTarget(Item item, Building source, boolean flip){
             int dir = source.relativeTo(tile.x, tile.y);
             if(dir == -1) return null;
             Building to;
diff --git a/core/src/mindustry/world/blocks/distribution/StackConveyor.java b/core/src/mindustry/world/blocks/distribution/StackConveyor.java
index 6526f973a5..06d5bc7cff 100644
--- a/core/src/mindustry/world/blocks/distribution/StackConveyor.java
+++ b/core/src/mindustry/world/blocks/distribution/StackConveyor.java
@@ -147,7 +147,7 @@ public class StackConveyor extends Block implements Autotiler{
             int[] bits = buildBlending(tile, rotation, null, true);
             if(bits[0] == 0 &&  blends(tile, rotation, 0) && !blends(tile, rotation, 2)) state = stateLoad;  // a 0 that faces into a conveyor with none behind it
             if(bits[0] == 0 && !blends(tile, rotation, 0) && blends(tile, rotation, 2)) state = stateUnload; // a 0 that faces into none with a conveyor behind it
-            
+
             blendprox = 0;
 
             for(int i = 0; i < 4; i++){
@@ -219,12 +219,12 @@ public class StackConveyor extends Block implements Autotiler{
             return false; // has no moving parts;
         }
 
-        private void poofIn(){
+        protected void poofIn(){
             link = tile.pos();
             Fx.plasticburn.at(this);
         }
 
-        private void poofOut(){
+        protected void poofOut(){
             Fx.plasticburn.at(this);
             link = -1;
         }