diff --git a/.gitignore b/.gitignore
index a007f0d..77b3a40 100644
--- a/.gitignore
+++ b/.gitignore
@@ -36,8 +36,6 @@ gradle-app.setting
 *.tar.gz
 *.rar
 
-*.minisig
-
 # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
 replay_pid*
diff --git a/app/src/main/java/hatelace/Address.java b/app/src/main/java/hatelace/Address.java
index f914865..fb4d249 100644
--- a/app/src/main/java/hatelace/Address.java
+++ b/app/src/main/java/hatelace/Address.java
@@ -1,6 +1,6 @@
 package hatelace;
 
-public class Address implements Operand {
+public class Address {
     int address;
 
     public Address(int address) {
@@ -14,8 +14,4 @@ public class Address implements Operand {
     public String toString() {
         return Integer.toString(address);
     }
-
-    public Word getWord(Memory memory) {
-        return memory.read(this);
-    }
 }
diff --git a/app/src/main/java/hatelace/Operand.java b/app/src/main/java/hatelace/Operand.java
deleted file mode 100644
index bcdc6be..0000000
--- a/app/src/main/java/hatelace/Operand.java
+++ /dev/null
@@ -1,5 +0,0 @@
-package hatelace;
-
-public interface Operand {
-    Word getWord(Memory memory);
-}
diff --git a/app/src/main/java/hatelace/Word.java b/app/src/main/java/hatelace/Word.java
index b0bbb17..db74dbc 100644
--- a/app/src/main/java/hatelace/Word.java
+++ b/app/src/main/java/hatelace/Word.java
@@ -1,6 +1,6 @@
 package hatelace;
 
-public abstract class Word implements Operand {
+public abstract class Word {
     public abstract <T> T getValue();
     public abstract Word add(Word other);
     public abstract Word subtract(Word other);
diff --git a/app/src/main/java/hatelace/instructions/Add.java b/app/src/main/java/hatelace/instructions/Add.java
index 1b88504..fc5c2ab 100644
--- a/app/src/main/java/hatelace/instructions/Add.java
+++ b/app/src/main/java/hatelace/instructions/Add.java
@@ -3,18 +3,19 @@ package hatelace.instructions;
 import hatelace.*;
 
 public class Add extends Instruction {
+    private Address src;
+    private Word imm;
     private Address dest;
-    private Operand o1, o2;
 
     /** Add immediate value to memory address. */
-    public Add(Operand o1, Operand o2, Address dest) {
-        this.o1 = o1;
-        this.o2 = o2;
+    public Add(Address src, Word imm, Address dest) {
+        this.src = src;
+        this.imm = imm;
         this.dest = dest;
     }
 
     public void execute(Memory memory, ProgramCounter PC) {
-        memory.write(this.dest, this.o1.getWord(memory).add(this.o2.getWord(memory)));
+        memory.write(this.dest, memory.read(this.src).add(this.imm));
         PC.incPC();
     }
 
@@ -23,10 +24,10 @@ public class Add extends Instruction {
     }
 
     public String toString() {
-        return String.format("%s [%s] %s [%s]", this.opcode(), this.o1, this.o2, this.dest);
+        return String.format("%s [%s] %s [%s]", this.opcode(), this.src, this.imm, this.dest);
     }
 
     protected Object[] operands() {
-        return new Object[] { this.o1, this.o2, this.dest };
+        return new Object[] { this.src, this.imm, this.dest };
     }
 }
diff --git a/app/src/main/java/hatelace/instructions/Copy.java b/app/src/main/java/hatelace/instructions/Copy.java
index a88c27e..985ce1a 100644
--- a/app/src/main/java/hatelace/instructions/Copy.java
+++ b/app/src/main/java/hatelace/instructions/Copy.java
@@ -3,17 +3,17 @@ package hatelace.instructions;
 import hatelace.*;
 
 public class Copy extends Instruction {
-    private Operand src;
+    private Word imm;
     private Address dest;
 
     /** Copy immediate value to memory address. */
-    public Copy(Operand src, Address dest) {
-        this.src = src;
+    public Copy(Word imm, Address dest) {
+        this.imm = imm;
         this.dest = dest;
     }
 
     public void execute(Memory memory, ProgramCounter PC) {
-        memory.write(this.dest, this.src.getWord(memory));
+        memory.write(this.dest, this.imm);
         PC.incPC();
     }
 
@@ -22,10 +22,10 @@ public class Copy extends Instruction {
     }
 
     protected Object[] operands() {
-        return new Object[] {this.src, this.dest};
+        return new Object[] {this.imm, this.dest};
     }
 
     public String toString() {
-        return String.format("%s %s [%s]", this.opcode(), this.src, this.dest);
+        return String.format("%s %s [%s]", this.opcode(), this.imm, this.dest);
     }
 }
diff --git a/app/src/main/java/hatelace/instructions/JumpEq.java b/app/src/main/java/hatelace/instructions/JumpEq.java
index a0b27ba..f2538be 100644
--- a/app/src/main/java/hatelace/instructions/JumpEq.java
+++ b/app/src/main/java/hatelace/instructions/JumpEq.java
@@ -4,18 +4,18 @@ import hatelace.*;
 
 public class JumpEq extends Instruction {
     private int index;
-    private Operand o1;
-    private Operand o2;
+    private Address src;
+    private Word imm;
 
     /** Conditional jump */
-    public JumpEq(int index, Operand o1, Operand o2) {
+    public JumpEq(int index, Address src, Word imm) {
         this.index = index;
-        this.o1 = o1;
-        this.o2 = o2;
+        this.src = src;
+        this.imm = imm;
     }
 
     public void execute(Memory memory, ProgramCounter PC) {
-        if (this.o1.getWord(memory).equals(this.o2.getWord(memory))) {
+        if (this.imm.equals(memory.read(this.src))) {
             PC.setPC(this.index);
         } else {
             PC.incPC();
@@ -27,10 +27,10 @@ public class JumpEq extends Instruction {
     }
 
     protected Object[] operands() {
-        return new Object[] {this.index, this.o1, this.o2};
+        return new Object[] {this.index, this.src, this.imm};
     }
 
     public String toString() {
-        return String.format("%s %s [%s] %s", this.opcode(), this.index, this.o1, this.o2);
+        return String.format("%s %s [%s] %s", this.opcode(), this.index, this.src, this.imm);
     }
 }
diff --git a/app/src/main/java/hatelace/instructions/Mul.java b/app/src/main/java/hatelace/instructions/Mul.java
index 4536682..cd61d81 100644
--- a/app/src/main/java/hatelace/instructions/Mul.java
+++ b/app/src/main/java/hatelace/instructions/Mul.java
@@ -3,19 +3,19 @@ package hatelace.instructions;
 import hatelace.*;
 
 public class Mul extends Instruction {
-    private Operand o1;
-    private Operand o2;
+    private Address src1;
+    private Address src2;
     private Address dest;
 
     /** Multiply contents of two addresses and store the result in a third memory address. */
-    public Mul(Operand o1, Operand o2, Address dest) {
-        this.o1 = o1;
-        this.o2 = o2;
+    public Mul(Address src1, Address src2, Address dest) {
+        this.src1 = src1;
+        this.src2 = src2;
         this.dest = dest;
     }
 
     public void execute(Memory memory, ProgramCounter PC) {
-        memory.write(this.dest, this.o1.getWord(memory).multiply(this.o2.getWord(memory)));
+        memory.write(this.dest, memory.read(this.src1).multiply(memory.read(this.src2)));
         PC.incPC();
     }
 
@@ -24,10 +24,10 @@ public class Mul extends Instruction {
     }
 
     protected Object[] operands() {
-        return new Object[] { this.o1, this.o2, this.dest };
+        return new Object[] { this.src1, this.src2, this.dest };
     }
 
     public String toString() {
-        return String.format("%s [%s] [%s] [%s]", this.opcode(), this.o1, this.o2, this.dest);
+        return String.format("%s [%s] [%s] [%s]", this.opcode(), this.src1, this.src2, this.dest);
     }
 }
diff --git a/app/src/main/java/hatelace/memtypes/IntWord.java b/app/src/main/java/hatelace/memtypes/IntWord.java
index ba8402d..75c00a8 100644
--- a/app/src/main/java/hatelace/memtypes/IntWord.java
+++ b/app/src/main/java/hatelace/memtypes/IntWord.java
@@ -1,6 +1,5 @@
 package hatelace.memtypes;
 
-import hatelace.Memory;
 import hatelace.Word;
 
 public class IntWord extends Word {
@@ -16,11 +15,6 @@ public class IntWord extends Word {
         return value;
     }
 
-    @Override
-    public Word getWord(Memory memory) {
-        return this;
-    }
-
     public Word add(Word other) {
         return new IntWord(value + (Integer) other.getValue());
     }
diff --git a/app/src/main/java/hatelace/memtypes/LongWord.java b/app/src/main/java/hatelace/memtypes/LongWord.java
index 272ffd5..f01ace2 100644
--- a/app/src/main/java/hatelace/memtypes/LongWord.java
+++ b/app/src/main/java/hatelace/memtypes/LongWord.java
@@ -1,6 +1,5 @@
 package hatelace.memtypes;
 
-import hatelace.Memory;
 import hatelace.Word;
 
 public class LongWord extends Word {
@@ -16,11 +15,6 @@ public class LongWord extends Word {
         return value;
     }
 
-    @Override
-    public Word getWord(Memory memory) {
-        return this;
-    }
-
     public Word add(Word other) {
         return new LongWord(value + (Long) other.getValue());
     }