diff --git a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/Cubot.java b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/Cubot.java
index 600fdb6..884db0a 100644
--- a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/Cubot.java	
+++ b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/Cubot.java	
@@ -1,7 +1,7 @@
 package net.simon987.cubotplugin;
 
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.assembly.CPU;
 import net.simon987.server.assembly.HardwareModule;
 import net.simon987.server.assembly.Memory;
@@ -128,7 +128,7 @@ public class Cubot extends GameObject implements Updatable, ControllableUnit, Me
         shield = document.getInteger("shield");
         setDirection(Direction.getDirection(document.getInteger("direction")));
 
-        ServerConfiguration config = GameServer.INSTANCE.getConfig();
+        IServerConfiguration config = GameServer.INSTANCE.getConfig();
         maxHp = config.getInt("cubot_max_hp");
         maxShield = config.getInt("cubot_max_shield");
 
@@ -278,7 +278,7 @@ public class Cubot extends GameObject implements Updatable, ControllableUnit, Me
         this.getWorld().removeObject(this);
         this.getWorld().decUpdatable();
 
-        ServerConfiguration config = GameServer.INSTANCE.getConfig();
+        IServerConfiguration config = GameServer.INSTANCE.getConfig();
         Random random = new Random();
 
         int spawnX = config.getInt("new_user_worldX") + random.nextInt(5);
diff --git a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/event/UserCreationListener.java b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/event/UserCreationListener.java
index c34c085..7a0e359 100644
--- a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/event/UserCreationListener.java	
+++ b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/event/UserCreationListener.java	
@@ -3,7 +3,7 @@ package net.simon987.cubotplugin.event;
 import net.simon987.cubotplugin.Cubot;
 import net.simon987.cubotplugin.CubotStatus;
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.assembly.Assembler;
 import net.simon987.server.assembly.AssemblyResult;
 import net.simon987.server.assembly.CPU;
@@ -33,7 +33,7 @@ public class UserCreationListener implements GameEventListener {
         Cubot cubot = new Cubot();
         cubot.addStatus(CubotStatus.FACTORY_NEW);
         cubot.setObjectId(new ObjectId());
-        ServerConfiguration config = GameServer.INSTANCE.getConfig();
+        IServerConfiguration config = GameServer.INSTANCE.getConfig();
 
         Point point = null;
         while (point == null || cubot.getWorld() == null) {
diff --git a/Plugin NPC/src/main/java/net/simon987/npcplugin/NpcPlugin.java b/Plugin NPC/src/main/java/net/simon987/npcplugin/NpcPlugin.java
index 79251d3..139bb66 100644
--- a/Plugin NPC/src/main/java/net/simon987/npcplugin/NpcPlugin.java	
+++ b/Plugin NPC/src/main/java/net/simon987/npcplugin/NpcPlugin.java	
@@ -7,7 +7,7 @@ import net.simon987.npcplugin.event.WorldCreationListener;
 import net.simon987.npcplugin.world.TileVaultFloor;
 import net.simon987.npcplugin.world.TileVaultWall;
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.game.objects.GameRegistry;
 import net.simon987.server.logging.LogManager;
 import net.simon987.server.plugin.ServerPlugin;
@@ -27,7 +27,7 @@ public class NpcPlugin extends ServerPlugin {
     @Override
     public void init(GameServer gameServer) {
 
-        ServerConfiguration configuration = gameServer.getConfig();
+        IServerConfiguration configuration = gameServer.getConfig();
         GameRegistry registry = gameServer.getRegistry();
 
         listeners.add(new WorldCreationListener(configuration.getInt("settlement_spawn_rate")));
diff --git a/Plugin NPC/src/main/java/net/simon987/npcplugin/VaultDimension.java b/Plugin NPC/src/main/java/net/simon987/npcplugin/VaultDimension.java
index 87a3cc1..feea1dc 100644
--- a/Plugin NPC/src/main/java/net/simon987/npcplugin/VaultDimension.java	
+++ b/Plugin NPC/src/main/java/net/simon987/npcplugin/VaultDimension.java	
@@ -2,7 +2,7 @@ package net.simon987.npcplugin;
 
 import net.simon987.npcplugin.world.TileVaultFloor;
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.game.objects.Direction;
 import net.simon987.server.game.world.Location;
 import net.simon987.server.game.world.World;
@@ -49,7 +49,7 @@ public class VaultDimension {
          * as a set of coordinates + a list of opening directions, then they are actually generated
          */
 
-        ServerConfiguration config = GameServer.INSTANCE.getConfig();
+        IServerConfiguration config = GameServer.INSTANCE.getConfig();
 
         int minLayerCount = config.getInt("vault_wg_min_layer_count");
         int maxLayerCount = config.getInt("vault_wg_max_layer_count");
diff --git a/Plugin NPC/src/main/java/net/simon987/npcplugin/event/VaultWorldUpdateListener.java b/Plugin NPC/src/main/java/net/simon987/npcplugin/event/VaultWorldUpdateListener.java
index 9e3188b..dc7594e 100644
--- a/Plugin NPC/src/main/java/net/simon987/npcplugin/event/VaultWorldUpdateListener.java	
+++ b/Plugin NPC/src/main/java/net/simon987/npcplugin/event/VaultWorldUpdateListener.java	
@@ -3,7 +3,7 @@ package net.simon987.npcplugin.event;
 import net.simon987.npcplugin.ElectricBox;
 import net.simon987.npcplugin.VaultWorldUtils;
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.event.GameEvent;
 import net.simon987.server.event.GameEventListener;
 import net.simon987.server.event.WorldUpdateEvent;
@@ -36,7 +36,7 @@ public class VaultWorldUpdateListener implements GameEventListener {
      */
     private static int electricBoxThreshold;
 
-    public VaultWorldUpdateListener(ServerConfiguration config) {
+    public VaultWorldUpdateListener(IServerConfiguration config) {
 
         minElectricBoxCount = config.getInt("min_electric_box_respawn_count");
         maxElectricBoxCount = config.getInt("max_electric_box_respawn_count");
diff --git a/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassPlugin.java b/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassPlugin.java
index 70f09b2..4f7c7da 100644
--- a/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassPlugin.java	
+++ b/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassPlugin.java	
@@ -4,7 +4,7 @@ import net.simon987.biomassplugin.event.ObjectDeathListener;
 import net.simon987.biomassplugin.event.WorldCreationListener;
 import net.simon987.biomassplugin.event.WorldUpdateListener;
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.game.objects.GameRegistry;
 import net.simon987.server.logging.LogManager;
 import net.simon987.server.plugin.ServerPlugin;
@@ -16,7 +16,7 @@ public class BiomassPlugin extends ServerPlugin {
     @Override
     public void init(GameServer gameServer) {
 
-        ServerConfiguration config = gameServer.getConfig();
+        IServerConfiguration config = gameServer.getConfig();
         GameRegistry registry = gameServer.getRegistry();
 
         listeners.add(new WorldCreationListener());
diff --git a/Plugin Plant/src/main/java/net/simon987/biomassplugin/event/ObjectDeathListener.java b/Plugin Plant/src/main/java/net/simon987/biomassplugin/event/ObjectDeathListener.java
index 023c66f..eb7d9b1 100644
--- a/Plugin Plant/src/main/java/net/simon987/biomassplugin/event/ObjectDeathListener.java	
+++ b/Plugin Plant/src/main/java/net/simon987/biomassplugin/event/ObjectDeathListener.java	
@@ -1,7 +1,7 @@
 package net.simon987.biomassplugin.event;
 
 import net.simon987.biomassplugin.BiomassBlob;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.event.GameEvent;
 import net.simon987.server.event.GameEventListener;
 import net.simon987.server.event.ObjectDeathEvent;
@@ -16,7 +16,7 @@ public class ObjectDeathListener implements GameEventListener {
 
     private int biomassDropCount;
 
-    public ObjectDeathListener(ServerConfiguration config) {
+    public ObjectDeathListener(IServerConfiguration config) {
         biomassDropCount = config.getInt("harvester_biomass_drop_count");
     }
 
diff --git a/Plugin Plant/src/main/java/net/simon987/biomassplugin/event/WorldUpdateListener.java b/Plugin Plant/src/main/java/net/simon987/biomassplugin/event/WorldUpdateListener.java
index bf65a37..62b77cb 100644
--- a/Plugin Plant/src/main/java/net/simon987/biomassplugin/event/WorldUpdateListener.java	
+++ b/Plugin Plant/src/main/java/net/simon987/biomassplugin/event/WorldUpdateListener.java	
@@ -3,7 +3,7 @@ package net.simon987.biomassplugin.event;
 import net.simon987.biomassplugin.BiomassBlob;
 import net.simon987.biomassplugin.WorldUtils;
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.event.GameEvent;
 import net.simon987.server.event.GameEventListener;
 import net.simon987.server.event.WorldUpdateEvent;
@@ -23,7 +23,7 @@ public class WorldUpdateListener implements GameEventListener {
     private static int waitTime;
     private static int blobThreshold;
 
-    public WorldUpdateListener(ServerConfiguration config) {
+    public WorldUpdateListener(IServerConfiguration config) {
 
         minBlobCount = config.getInt("minBiomassRespawnCount");
         maxBlobCount = config.getInt("maxBiomassRespawnCount");
diff --git a/Server/src/main/java/net/simon987/server/GameServer.java b/Server/src/main/java/net/simon987/server/GameServer.java
index 8b542a5..e7faa8e 100644
--- a/Server/src/main/java/net/simon987/server/GameServer.java
+++ b/Server/src/main/java/net/simon987/server/GameServer.java
@@ -33,7 +33,7 @@ public class GameServer implements Runnable {
     private GameEventDispatcher eventDispatcher;
     private PluginManager pluginManager;
 
-    private ServerConfiguration config;
+    private IServerConfiguration config;
 
     private SocketServer socketServer;
 
@@ -308,7 +308,7 @@ public class GameServer implements Runnable {
         }
     }
 
-    public ServerConfiguration getConfig() {
+    public IServerConfiguration getConfig() {
         return config;
     }
 
diff --git a/Server/src/main/java/net/simon987/server/IServerConfiguration.java b/Server/src/main/java/net/simon987/server/IServerConfiguration.java
new file mode 100644
index 0000000..7696862
--- /dev/null
+++ b/Server/src/main/java/net/simon987/server/IServerConfiguration.java
@@ -0,0 +1,12 @@
+package net.simon987.server;
+
+public interface IServerConfiguration {
+
+    int getInt(String key);
+
+    String getString(String key);
+
+    void setInt(String key, int value);
+
+    void setString(String key, String value);
+}
diff --git a/Server/src/main/java/net/simon987/server/ServerConfiguration.java b/Server/src/main/java/net/simon987/server/ServerConfiguration.java
index bb8966d..61eac06 100644
--- a/Server/src/main/java/net/simon987/server/ServerConfiguration.java
+++ b/Server/src/main/java/net/simon987/server/ServerConfiguration.java
@@ -9,11 +9,15 @@ import java.util.Properties;
 /**
  * Wrapper for Java Properties class
  */
-public class ServerConfiguration {
+public class ServerConfiguration implements IServerConfiguration {
 
     private Properties properties;
     private String fileName;
 
+    public ServerConfiguration() {
+        this.properties = new Properties();
+    }
+
     public ServerConfiguration(String fileName) {
 
         this.fileName = fileName;
diff --git a/Server/src/main/java/net/simon987/server/assembly/Assembler.java b/Server/src/main/java/net/simon987/server/assembly/Assembler.java
index e84d674..1e31834 100755
--- a/Server/src/main/java/net/simon987/server/assembly/Assembler.java
+++ b/Server/src/main/java/net/simon987/server/assembly/Assembler.java
@@ -1,7 +1,6 @@
 package net.simon987.server.assembly;
 
-import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.assembly.exception.*;
 import net.simon987.server.logging.LogManager;
 import org.apache.commons.text.StringEscapeUtils;
@@ -19,18 +18,22 @@ import java.util.regex.Pattern;
  */
 public class Assembler {
 
-    private ServerConfiguration config;
+    private IServerConfiguration config;
 
     private InstructionSet instructionSet;
 
     private RegisterSet registerSet;
 
-    private static final int MEM_SIZE = GameServer.INSTANCE.getConfig().getInt("memory_size");
+    private static int MEM_SIZE;
+    private static String labelPattern = "^\\s*[a-zA-Z_]\\w*:";
+    private static Pattern commentPattern = Pattern.compile("\"[^\"]*\"|(;)");
 
-    public Assembler(InstructionSet instructionSet, RegisterSet registerSet, ServerConfiguration config) {
+    public Assembler(InstructionSet instructionSet, RegisterSet registerSet, IServerConfiguration config) {
         this.instructionSet = instructionSet;
         this.registerSet = registerSet;
         this.config = config;
+
+        Assembler.MEM_SIZE = config.getInt("memory_size");
     }
 
     /**
@@ -40,11 +43,17 @@ public class Assembler {
      * @return The line without its comment part
      */
     private static String removeComment(String line) {
-        if (line.indexOf(';') != -1) {
-            return line.substring(0, line.indexOf(';'));
-        } else {
-            return line;
+
+        Matcher m = commentPattern.matcher(line);
+
+        while (m.find()) {
+            try {
+                return line.substring(0, m.start(1));
+            } catch (IndexOutOfBoundsException ignored) {
+            }
         }
+
+        return line;
     }
 
     /**
@@ -55,8 +64,7 @@ public class Assembler {
      */
     private static String removeLabel(String line) {
 
-        return line.replaceAll("^\\s*\\b\\w*\\b:", "");
-
+        return line.replaceAll(labelPattern, "");
     }
 
     /**
@@ -98,7 +106,7 @@ public class Assembler {
         line = removeComment(line);
 
         //Check for labels
-        Pattern pattern = Pattern.compile("^\\s*\\b\\w*\\b:");
+        Pattern pattern = Pattern.compile(labelPattern);
         Matcher matcher = pattern.matcher(line);
 
         if (matcher.find()) {
@@ -161,7 +169,7 @@ public class Assembler {
                             string = StringEscapeUtils.unescapeJava(string);
                         } catch (IllegalArgumentException e) {
                             throw new InvalidOperandException(
-                                "Invalid string operand \"" + string + "\": " + e.getMessage(), 
+                                    "Invalid string operand \"" + string + "\": " + e.getMessage(),
                                 currentLine);
                         }
 
diff --git a/Server/src/main/java/net/simon987/server/assembly/AssemblyResult.java b/Server/src/main/java/net/simon987/server/assembly/AssemblyResult.java
index 0798b06..3268fbb 100755
--- a/Server/src/main/java/net/simon987/server/assembly/AssemblyResult.java
+++ b/Server/src/main/java/net/simon987/server/assembly/AssemblyResult.java
@@ -1,6 +1,6 @@
 package net.simon987.server.assembly;
 
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.assembly.exception.AssemblyException;
 import net.simon987.server.assembly.exception.DuplicateSectionException;
 import net.simon987.server.logging.LogManager;
@@ -59,7 +59,7 @@ public class AssemblyResult {
      */
     private boolean dataSectionSet = false;
 
-    AssemblyResult(ServerConfiguration config) {
+    AssemblyResult(IServerConfiguration config) {
         origin = config.getInt("org_offset");
     }
 
diff --git a/Server/src/main/java/net/simon987/server/assembly/CPU.java b/Server/src/main/java/net/simon987/server/assembly/CPU.java
index 8fa9c30..0cd4e96 100755
--- a/Server/src/main/java/net/simon987/server/assembly/CPU.java
+++ b/Server/src/main/java/net/simon987/server/assembly/CPU.java
@@ -1,7 +1,7 @@
 package net.simon987.server.assembly;
 
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.assembly.exception.CancelledException;
 import net.simon987.server.assembly.instruction.*;
 import net.simon987.server.event.CpuInitialisationEvent;
@@ -98,7 +98,7 @@ public class CPU implements MongoSerializable {
     /**
      * Creates a new CPU
      */
-    public CPU(ServerConfiguration config, ControllableUnit unit) throws CancelledException {
+    public CPU(IServerConfiguration config, ControllableUnit unit) throws CancelledException {
         instructionSet = new DefaultInstructionSet();
         registerSet = new DefaultRegisterSet();
         codeSectionOffset = config.getInt("org_offset");
diff --git a/Server/src/main/java/net/simon987/server/game/GameUniverse.java b/Server/src/main/java/net/simon987/server/game/GameUniverse.java
index 85c3f20..4afb1ca 100644
--- a/Server/src/main/java/net/simon987/server/game/GameUniverse.java
+++ b/Server/src/main/java/net/simon987/server/game/GameUniverse.java
@@ -5,7 +5,7 @@ import com.mongodb.client.MongoCollection;
 import com.mongodb.client.MongoCursor;
 import com.mongodb.client.MongoDatabase;
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.assembly.exception.CancelledException;
 import net.simon987.server.game.objects.GameObject;
 import net.simon987.server.game.world.World;
@@ -32,7 +32,7 @@ public class GameUniverse {
 
     private int maxWidth = 0xFFFF;
 
-    public GameUniverse(ServerConfiguration config) {
+    public GameUniverse(IServerConfiguration config) {
 
         worlds = new ConcurrentHashMap<>(256);
         users = new ConcurrentHashMap<>(16);
diff --git a/Server/src/main/java/net/simon987/server/game/world/WorldGenerator.java b/Server/src/main/java/net/simon987/server/game/world/WorldGenerator.java
index 1550e43..980acf4 100755
--- a/Server/src/main/java/net/simon987/server/game/world/WorldGenerator.java
+++ b/Server/src/main/java/net/simon987/server/game/world/WorldGenerator.java
@@ -1,7 +1,7 @@
 package net.simon987.server.game.world;
 
 import net.simon987.server.GameServer;
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.assembly.exception.CancelledException;
 import net.simon987.server.event.GameEvent;
 import net.simon987.server.event.WorldGenerationEvent;
@@ -48,7 +48,7 @@ public class WorldGenerator {
     private HashMap<Point, Integer> centerPointsMap;
 
 
-    public WorldGenerator(ServerConfiguration config) {
+    public WorldGenerator(IServerConfiguration config) {
 
         dimension = config.getString("new_user_dimension");
 
diff --git a/Server/src/main/java/net/simon987/server/web/WebServer.java b/Server/src/main/java/net/simon987/server/web/WebServer.java
index e1d59f3..475bd9a 100644
--- a/Server/src/main/java/net/simon987/server/web/WebServer.java
+++ b/Server/src/main/java/net/simon987/server/web/WebServer.java
@@ -1,6 +1,6 @@
 package net.simon987.server.web;
 
-import net.simon987.server.ServerConfiguration;
+import net.simon987.server.IServerConfiguration;
 import net.simon987.server.logging.LogManager;
 import net.simon987.server.websocket.SocketServer;
 import org.apache.velocity.app.VelocityEngine;
@@ -14,7 +14,7 @@ public class WebServer {
     private SocketServer socketServer;
     private GuestPolicy guestPolicy;
 
-    public WebServer(ServerConfiguration config) {
+    public WebServer(IServerConfiguration config) {
 
         //Velocity config
         Properties properties = new Properties();
@@ -63,7 +63,7 @@ public class WebServer {
      * Load guest policy from config.
      * If no valid policy is specified in the config, the default <code>GuestPolicy.ALLOW</code> is used
      */
-    private void initGuestPolicy(ServerConfiguration config) {
+    private void initGuestPolicy(IServerConfiguration config) {
         String guestPolicyStr = config.getString("guest_policy");
         try {
             this.guestPolicy = GuestPolicy.valueOf(guestPolicyStr);
diff --git a/Server/src/main/resources/static/js/editor.js b/Server/src/main/resources/static/js/editor.js
index 7087fe2..7d98023 100644
--- a/Server/src/main/resources/static/js/editor.js
+++ b/Server/src/main/resources/static/js/editor.js
@@ -28,7 +28,7 @@ function checkForLabel(line, result) {
     line = removeComment(line);
 
     var match;
-    if ((match = /\b\w*\b:/.exec(line)) !== null) {
+    if ((match = /^[a-zA-Z_]\w*:/.exec(line)) !== null) {
 
         result.labels.push(match[0].substring(0, match[0].length - 1));
     }
diff --git a/Server/src/test/java/net/simon987/server/FakeConfiguration.java b/Server/src/test/java/net/simon987/server/FakeConfiguration.java
new file mode 100644
index 0000000..5c30572
--- /dev/null
+++ b/Server/src/test/java/net/simon987/server/FakeConfiguration.java
@@ -0,0 +1,33 @@
+package net.simon987.server;
+
+import java.util.Properties;
+
+public class FakeConfiguration implements IServerConfiguration {
+
+    private Properties properties;
+
+
+    public FakeConfiguration() {
+        this.properties = new Properties();
+    }
+
+    @Override
+    public int getInt(String key) {
+        return Integer.parseInt(properties.getProperty(key));
+    }
+
+    @Override
+    public String getString(String key) {
+        return properties.getProperty(key);
+    }
+
+    @Override
+    public void setInt(String key, int value) {
+        properties.setProperty(key, String.valueOf(value));
+    }
+
+    @Override
+    public void setString(String key, String value) {
+        properties.setProperty(key, value);
+    }
+}
diff --git a/Server/src/test/java/net/simon987/server/assembly/DWTest.java b/Server/src/test/java/net/simon987/server/assembly/DWTest.java
new file mode 100644
index 0000000..a8f15bb
--- /dev/null
+++ b/Server/src/test/java/net/simon987/server/assembly/DWTest.java
@@ -0,0 +1,24 @@
+package net.simon987.server.assembly;
+
+import net.simon987.server.FakeConfiguration;
+import net.simon987.server.IServerConfiguration;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class DWTest {
+
+    @Test
+    public void TestSemiColonInString() {
+
+        IServerConfiguration configuration = new FakeConfiguration();
+
+        configuration.setInt("memory_size", 1000);
+        configuration.setInt("org_offset", 400);
+
+        Assembler assembler = new Assembler(new DefaultInstructionSet(), new DefaultRegisterSet(), configuration);
+
+        AssemblyResult ar = assembler.parse("DW \";\"");
+        assertEquals(0, ar.exceptions.size());
+    }
+}
diff --git a/Server/src/test/java/net/simon987/server/assembly/LabelTest.java b/Server/src/test/java/net/simon987/server/assembly/LabelTest.java
new file mode 100644
index 0000000..30c043b
--- /dev/null
+++ b/Server/src/test/java/net/simon987/server/assembly/LabelTest.java
@@ -0,0 +1,30 @@
+package net.simon987.server.assembly;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+public class LabelTest {
+
+    @Test
+    public void TestNumericLabel() {
+
+        Assembler asm = TestHelper.getTestAsm();
+
+        AssemblyResult ar = asm.parse("999:");
+
+        assertEquals(ar.labels.size(), 0);
+    }
+
+    @Test
+    public void TestValidLabel() {
+
+        Assembler asm = TestHelper.getTestAsm();
+
+        AssemblyResult ar = asm.parse("\ttest_label: dw 1 ; comment");
+
+        assertNotNull(ar.labels.get("test_label"));
+    }
+
+}
diff --git a/Server/src/test/java/net/simon987/server/assembly/TestComment.java b/Server/src/test/java/net/simon987/server/assembly/TestComment.java
new file mode 100644
index 0000000..3633a7b
--- /dev/null
+++ b/Server/src/test/java/net/simon987/server/assembly/TestComment.java
@@ -0,0 +1,38 @@
+package net.simon987.server.assembly;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class TestComment {
+
+    @Test
+    public void TestCommentInQuotes() {
+
+        Assembler asm = TestHelper.getTestAsm();
+
+        AssemblyResult r1 = asm.parse("dw \";\", 12");
+        assertEquals(r1.bytes.length, 4);
+    }
+
+    @Test
+    public void TestRegularComment() {
+
+        Assembler asm = TestHelper.getTestAsm();
+
+        AssemblyResult r1 = asm.parse("register_SP: DW \"SP=\",0 ; register_A + 28");
+        assertEquals(8, r1.bytes.length);
+        assertEquals(0, r1.exceptions.size());
+    }
+
+    @Test
+    public void TestStandaloneComment() {
+
+        Assembler asm = TestHelper.getTestAsm();
+
+        AssemblyResult r1 = asm.parse("; Set display_mode to DECIMAL_MODE");
+        assertEquals(0, r1.bytes.length);
+        assertEquals(0, r1.exceptions.size());
+    }
+
+}
diff --git a/Server/src/test/java/net/simon987/server/assembly/TestHelper.java b/Server/src/test/java/net/simon987/server/assembly/TestHelper.java
new file mode 100644
index 0000000..e035b73
--- /dev/null
+++ b/Server/src/test/java/net/simon987/server/assembly/TestHelper.java
@@ -0,0 +1,18 @@
+package net.simon987.server.assembly;
+
+import net.simon987.server.FakeConfiguration;
+import net.simon987.server.IServerConfiguration;
+
+class TestHelper {
+
+    static Assembler getTestAsm() {
+
+        IServerConfiguration configuration = new FakeConfiguration();
+
+        configuration.setInt("memory_size", 1000);
+        configuration.setInt("org_offset", 400);
+
+        return new Assembler(new DefaultInstructionSet(), new DefaultRegisterSet(), configuration);
+    }
+
+}