diff --git a/src/main/java/org/dynjs/debugger/Debugger.java b/src/main/java/org/dynjs/debugger/Debugger.java
index 7ba8d1b72..8be60f97e 100644
--- a/src/main/java/org/dynjs/debugger/Debugger.java
+++ b/src/main/java/org/dynjs/debugger/Debugger.java
@@ -8,6 +8,7 @@
 import org.dynjs.debugger.requests.Response;
 import org.dynjs.parser.Statement;
 import org.dynjs.runtime.ExecutionContext;
+import org.dynjs.runtime.SourceProvider;
 
 import java.util.*;
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -43,6 +44,8 @@ public enum StepAction {
 
     private ReferenceManager referenceManager = new ReferenceManager();
 
+    private Set<SourceProvider> sources = new HashSet<>();
+
     private boolean paused = false;
     private Statement currentStatement = null;
 
@@ -95,12 +98,17 @@ public ExecutionContext getCurrentContext() {
 
     public void enterContext(ExecutionContext context) {
         this.contextStack.add(0, context);
+        this.sources.add(context.getSource());
     }
 
     public void exitContext(ExecutionContext context) {
         this.contextStack.remove(0);
     }
 
+    public Set<SourceProvider> getSources() {
+        return this.sources;
+    }
+
     public boolean isRunning() {
         return ! this.paused;
     }
diff --git a/src/main/java/org/dynjs/debugger/agent/JSONEncoder.java b/src/main/java/org/dynjs/debugger/agent/JSONEncoder.java
index 15c594052..ff9c1ec13 100644
--- a/src/main/java/org/dynjs/debugger/agent/JSONEncoder.java
+++ b/src/main/java/org/dynjs/debugger/agent/JSONEncoder.java
@@ -7,6 +7,7 @@
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelPromise;
 import org.dynjs.debugger.Debugger;
+import org.dynjs.debugger.agent.serializers.*;
 import org.dynjs.debugger.events.ConnectEvent;
 import org.dynjs.debugger.events.EventWrapper;
 import org.dynjs.debugger.requests.ResponseWrapper;
@@ -32,6 +33,7 @@ public JSONEncoder(Debugger debugger) {
         this.module.addSerializer( new ResponseWrapperSerializer( handleSerializer ) );
         this.module.addSerializer( new EvaluateResponseSerializer( handleSerializer ) );
         this.module.addSerializer( new LookupResponseSerializer( handleSerializer ) );
+        this.module.addSerializer( new ScriptsResponseSerializer( handleSerializer ) );
     }
 
     @Override
diff --git a/src/main/java/org/dynjs/debugger/agent/EvaluateResponseSerializer.java b/src/main/java/org/dynjs/debugger/agent/serializers/EvaluateResponseSerializer.java
similarity index 88%
rename from src/main/java/org/dynjs/debugger/agent/EvaluateResponseSerializer.java
rename to src/main/java/org/dynjs/debugger/agent/serializers/EvaluateResponseSerializer.java
index 4d9a099ce..f01b5107f 100644
--- a/src/main/java/org/dynjs/debugger/agent/EvaluateResponseSerializer.java
+++ b/src/main/java/org/dynjs/debugger/agent/serializers/EvaluateResponseSerializer.java
@@ -1,4 +1,4 @@
-package org.dynjs.debugger.agent;
+package org.dynjs.debugger.agent.serializers;
 
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonProcessingException;
@@ -15,7 +15,7 @@ public class EvaluateResponseSerializer extends StdSerializer<EvaluateResponse>
 
     private final HandleSerializer handleSerializer;
 
-    EvaluateResponseSerializer(HandleSerializer handleSerializer) {
+    public EvaluateResponseSerializer(HandleSerializer handleSerializer) {
         super(EvaluateResponse.class);
         this.handleSerializer = handleSerializer;
     }
diff --git a/src/main/java/org/dynjs/debugger/agent/HandleSerializer.java b/src/main/java/org/dynjs/debugger/agent/serializers/HandleSerializer.java
similarity index 82%
rename from src/main/java/org/dynjs/debugger/agent/HandleSerializer.java
rename to src/main/java/org/dynjs/debugger/agent/serializers/HandleSerializer.java
index 080e22367..43014bfc2 100644
--- a/src/main/java/org/dynjs/debugger/agent/HandleSerializer.java
+++ b/src/main/java/org/dynjs/debugger/agent/serializers/HandleSerializer.java
@@ -1,14 +1,11 @@
-package org.dynjs.debugger.agent;
+package org.dynjs.debugger.agent.serializers;
 
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonSerializer;
 import com.fasterxml.jackson.databind.SerializerProvider;
 import org.dynjs.debugger.Debugger;
-import org.dynjs.runtime.JSObject;
-import org.dynjs.runtime.NameEnumerator;
-import org.dynjs.runtime.PropertyDescriptor;
-import org.dynjs.runtime.Types;
+import org.dynjs.runtime.*;
 
 import java.io.IOException;
 
@@ -19,7 +16,7 @@ public class HandleSerializer extends JsonSerializer<Object> {
 
     private Debugger debugger;
 
-    HandleSerializer(Debugger debugger) {
+    public HandleSerializer(Debugger debugger) {
         super();
         this.debugger = debugger;
     }
@@ -33,8 +30,8 @@ public void serialize(Object value, JsonGenerator jgen, SerializerProvider provi
 
     public void serializeAsMapEntry(Object value, JsonGenerator jgen, SerializerProvider provider) throws IOException, JsonProcessingException {
         int ref = this.debugger.getReferenceManager().getReference(value);
-        jgen.writeFieldName( "" + ref );
-        serialize( value, jgen, provider );
+        jgen.writeFieldName("" + ref);
+        serialize(value, jgen, provider);
     }
 
     public void serializeBody(Object value, JsonGenerator jgen, SerializerProvider provider) throws IOException, JsonProcessingException {
@@ -60,9 +57,24 @@ public void serializeBody(Object value, JsonGenerator jgen, SerializerProvider p
         } else if (value instanceof JSObject) {
             jgen.writeStringField("type", "object");
             serializeJSObject((JSObject) value, jgen, provider);
+        } else if (value instanceof SourceProvider) {
+            serializeScript((SourceProvider) value, false, jgen, provider);
         }
     }
 
+    public void serializeScript(SourceProvider value, boolean includeSource, JsonGenerator jgen, SerializerProvider provider) throws IOException {
+        jgen.writeStringField("type", "script");
+        jgen.writeStringField("name", value.getName());
+        jgen.writeNumberField("id", value.getId());
+        if (includeSource) {
+            jgen.writeStringField("source", value.getSource());
+        }
+        jgen.writeNumberField("sourceLength", value.getSourceLength());
+        jgen.writeNumberField("lineCount", value.getLineCount());
+        jgen.writeNumberField("scriptType", 2);
+        jgen.writeNumberField("compilationType", 0);
+    }
+
     private void serializeJSObject(JSObject result, JsonGenerator jgen, SerializerProvider provider) throws IOException {
         jgen.writeFieldName("properties");
 
diff --git a/src/main/java/org/dynjs/debugger/agent/LookupResponseSerializer.java b/src/main/java/org/dynjs/debugger/agent/serializers/LookupResponseSerializer.java
similarity index 86%
rename from src/main/java/org/dynjs/debugger/agent/LookupResponseSerializer.java
rename to src/main/java/org/dynjs/debugger/agent/serializers/LookupResponseSerializer.java
index 6fd148fbe..3e3e872ad 100644
--- a/src/main/java/org/dynjs/debugger/agent/LookupResponseSerializer.java
+++ b/src/main/java/org/dynjs/debugger/agent/serializers/LookupResponseSerializer.java
@@ -1,10 +1,9 @@
-package org.dynjs.debugger.agent;
+package org.dynjs.debugger.agent.serializers;
 
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.SerializerProvider;
 import com.fasterxml.jackson.databind.ser.std.StdSerializer;
-import org.dynjs.debugger.requests.EvaluateResponse;
 import org.dynjs.debugger.requests.LookupResponse;
 
 import java.io.IOException;
@@ -16,7 +15,7 @@ public class LookupResponseSerializer extends StdSerializer<LookupResponse> {
 
     private final HandleSerializer handleSerializer;
 
-    LookupResponseSerializer(HandleSerializer handleSerializer) {
+    public LookupResponseSerializer(HandleSerializer handleSerializer) {
         super(LookupResponse.class);
         this.handleSerializer = handleSerializer;
     }
diff --git a/src/main/java/org/dynjs/debugger/agent/ResponseWrapperSerializer.java b/src/main/java/org/dynjs/debugger/agent/serializers/ResponseWrapperSerializer.java
similarity index 88%
rename from src/main/java/org/dynjs/debugger/agent/ResponseWrapperSerializer.java
rename to src/main/java/org/dynjs/debugger/agent/serializers/ResponseWrapperSerializer.java
index 81a8583b4..7520d5f7d 100644
--- a/src/main/java/org/dynjs/debugger/agent/ResponseWrapperSerializer.java
+++ b/src/main/java/org/dynjs/debugger/agent/serializers/ResponseWrapperSerializer.java
@@ -1,13 +1,13 @@
-package org.dynjs.debugger.agent;
+package org.dynjs.debugger.agent.serializers;
 
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.SerializerProvider;
 import com.fasterxml.jackson.databind.ser.std.StdSerializer;
-import org.dynjs.debugger.requests.EvaluateResponse;
 import org.dynjs.debugger.requests.ResponseWrapper;
 
 import java.io.IOException;
+import java.util.Collection;
 import java.util.List;
 
 /**
@@ -17,7 +17,7 @@ public class ResponseWrapperSerializer extends StdSerializer<ResponseWrapper> {
 
     private final HandleSerializer handleSerializer;
 
-    ResponseWrapperSerializer(HandleSerializer handleSerializer) {
+    public ResponseWrapperSerializer(HandleSerializer handleSerializer) {
         super(ResponseWrapper.class);
         this.handleSerializer = handleSerializer;
     }
@@ -39,7 +39,7 @@ public void serialize(ResponseWrapper value, JsonGenerator jgen, SerializerProvi
         jgen.writeFieldName( "refs" );
 
         jgen.writeStartArray();
-        List<Object> refs = value.getRefs();
+        Collection<? extends Object> refs = value.getRefs();
         for ( Object each : refs ) {
             this.handleSerializer.serialize(each, jgen, provider );
         }
diff --git a/src/main/java/org/dynjs/debugger/agent/serializers/ScriptsResponseSerializer.java b/src/main/java/org/dynjs/debugger/agent/serializers/ScriptsResponseSerializer.java
new file mode 100644
index 000000000..1583554dd
--- /dev/null
+++ b/src/main/java/org/dynjs/debugger/agent/serializers/ScriptsResponseSerializer.java
@@ -0,0 +1,37 @@
+package org.dynjs.debugger.agent.serializers;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.ser.std.StdSerializer;
+import org.dynjs.debugger.requests.ScriptsResponse;
+import org.dynjs.runtime.SourceProvider;
+
+import java.io.IOException;
+
+/**
+ * @author Bob McWhirter
+ */
+public class ScriptsResponseSerializer extends StdSerializer<ScriptsResponse> {
+
+    private final HandleSerializer handleSerializer;
+
+    public ScriptsResponseSerializer(HandleSerializer handleSerializer) {
+        super(ScriptsResponse.class);
+        this.handleSerializer = handleSerializer;
+    }
+
+    @Override
+    public void serialize(ScriptsResponse value, JsonGenerator jgen, SerializerProvider provider) throws IOException, JsonProcessingException {
+
+        jgen.writeStartArray();
+
+        for ( SourceProvider each : value.getScripts() )  {
+            this.handleSerializer.serializeScript( each, value.isIncludeSource(), jgen, provider );
+        }
+
+        jgen.writeEndArray();
+    }
+
+
+}
diff --git a/src/main/java/org/dynjs/debugger/commands/Scripts.java b/src/main/java/org/dynjs/debugger/commands/Scripts.java
index db5a56a13..c4e12aa04 100644
--- a/src/main/java/org/dynjs/debugger/commands/Scripts.java
+++ b/src/main/java/org/dynjs/debugger/commands/Scripts.java
@@ -3,6 +3,10 @@
 import org.dynjs.debugger.Debugger;
 import org.dynjs.debugger.requests.ScriptsRequest;
 import org.dynjs.debugger.requests.ScriptsResponse;
+import org.dynjs.runtime.SourceProvider;
+
+import java.util.HashSet;
+import java.util.Set;
 
 /**
  * @author Bob McWhirter
@@ -15,6 +19,28 @@ public Scripts(Debugger debugger) {
 
     @Override
     public ScriptsResponse handle(ScriptsRequest request) {
-        return new ScriptsResponse(request, true, true);
+        Set<SourceProvider> allScripts = this.debugger.getSources();
+        Set<SourceProvider> selectedScripts = null;
+
+        if (request.getArguments().getIds() == null) {
+            selectedScripts = allScripts;
+        } else {
+            selectedScripts = new HashSet<>();
+
+            int[] ids = request.getArguments().getIds();
+
+            for (SourceProvider each : allScripts) {
+                LOOKUP:
+                for (int i = 0; i < ids.length; ++i) {
+                    if (each.getId() == ids[i]) {
+                        selectedScripts.add(each);
+                        break LOOKUP;
+                    }
+                }
+            }
+
+        }
+
+        return new ScriptsResponse(request, selectedScripts, request.getArguments().isIncludeSource(), true, true);
     }
 }
diff --git a/src/main/java/org/dynjs/debugger/requests/AbstractResponse.java b/src/main/java/org/dynjs/debugger/requests/AbstractResponse.java
index 61afff8e3..a05504b71 100644
--- a/src/main/java/org/dynjs/debugger/requests/AbstractResponse.java
+++ b/src/main/java/org/dynjs/debugger/requests/AbstractResponse.java
@@ -3,6 +3,7 @@
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 
+import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 
@@ -47,7 +48,7 @@ public boolean isRunning() {
 
     @Override
     @JsonIgnore
-    public List<Object> getRefs() {
+    public Collection<? extends Object> getRefs() {
         return Collections.emptyList();
     }
 }
diff --git a/src/main/java/org/dynjs/debugger/requests/EvaluateResponse.java b/src/main/java/org/dynjs/debugger/requests/EvaluateResponse.java
index 9913cd06b..9aae54236 100644
--- a/src/main/java/org/dynjs/debugger/requests/EvaluateResponse.java
+++ b/src/main/java/org/dynjs/debugger/requests/EvaluateResponse.java
@@ -6,6 +6,7 @@
 import org.dynjs.runtime.Types;
 
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 
 /**
@@ -25,7 +26,7 @@ public Object getResult() {
     }
 
     @Override
-    public List<Object> getRefs() {
+    public Collection<Object> getRefs() {
         List<Object> refs = new ArrayList<>();
 
         getRefs( this.result, refs );
diff --git a/src/main/java/org/dynjs/debugger/requests/Response.java b/src/main/java/org/dynjs/debugger/requests/Response.java
index 507c69ee2..bc0ae83c4 100644
--- a/src/main/java/org/dynjs/debugger/requests/Response.java
+++ b/src/main/java/org/dynjs/debugger/requests/Response.java
@@ -3,6 +3,7 @@
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import org.dynjs.debugger.Message;
 
+import java.util.Collection;
 import java.util.List;
 
 /**
@@ -16,5 +17,5 @@ public interface Response extends Message {
     boolean isRunning();
 
     @JsonIgnore
-    List<Object> getRefs();
+    Collection<? extends Object> getRefs();
 }
diff --git a/src/main/java/org/dynjs/debugger/requests/ResponseWrapper.java b/src/main/java/org/dynjs/debugger/requests/ResponseWrapper.java
index fe04e3f60..a7be0a74c 100644
--- a/src/main/java/org/dynjs/debugger/requests/ResponseWrapper.java
+++ b/src/main/java/org/dynjs/debugger/requests/ResponseWrapper.java
@@ -3,6 +3,7 @@
 import com.fasterxml.jackson.annotation.JsonProperty;
 import org.dynjs.debugger.agent.handlers.WrappingHandler;
 
+import java.util.Collection;
 import java.util.List;
 
 /**
@@ -42,7 +43,7 @@ public int getSeq() {
         return this.seq;
     }
 
-    public List<Object> getRefs() {
+    public Collection<? extends Object> getRefs() {
         return this.body.getRefs();
     }
 
diff --git a/src/main/java/org/dynjs/debugger/requests/ScriptsRequest.java b/src/main/java/org/dynjs/debugger/requests/ScriptsRequest.java
index 90af902ec..248a640ab 100644
--- a/src/main/java/org/dynjs/debugger/requests/ScriptsRequest.java
+++ b/src/main/java/org/dynjs/debugger/requests/ScriptsRequest.java
@@ -12,6 +12,7 @@ public static class Arguments {
 
         private boolean includeSource;
         private int types;
+        private int[] ids;
 
         public void setIncludeSource(boolean includeSource) {
             this.includeSource = includeSource;
@@ -29,6 +30,14 @@ public int getTypes() {
             return this.types;
         }
 
+        public void setIds(int[] ids) {
+            this.ids = ids;
+        }
+
+        public int[] getIds() {
+            return this.ids;
+        }
+
     }
 
     private Arguments arguments;
diff --git a/src/main/java/org/dynjs/debugger/requests/ScriptsResponse.java b/src/main/java/org/dynjs/debugger/requests/ScriptsResponse.java
index 013f87603..564f636e6 100644
--- a/src/main/java/org/dynjs/debugger/requests/ScriptsResponse.java
+++ b/src/main/java/org/dynjs/debugger/requests/ScriptsResponse.java
@@ -1,11 +1,35 @@
 package org.dynjs.debugger.requests;
 
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import org.dynjs.runtime.SourceProvider;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.Set;
+
 /**
  * @author Bob McWhirter
  */
 public class ScriptsResponse extends AbstractResponse<ScriptsRequest> {
 
-    public ScriptsResponse(ScriptsRequest request, boolean success, boolean running) {
+    private final Set<SourceProvider> scripts;
+    private final boolean includeSource;
+
+    public ScriptsResponse(ScriptsRequest request, Set<SourceProvider> scripts, boolean includeSource, boolean success, boolean running) {
         super(request, success, running);
+        this.scripts = scripts;
+        this.includeSource = includeSource;
+    }
+
+    @JsonIgnore
+    public Collection<SourceProvider> getScripts() {
+        return this.scripts;
     }
+
+    @JsonIgnore
+    public boolean isIncludeSource() {
+        return this.includeSource;
+    }
+
+
 }
diff --git a/src/main/java/org/dynjs/runtime/Compiler.java b/src/main/java/org/dynjs/runtime/Compiler.java
index bd2035795..23345dfe0 100644
--- a/src/main/java/org/dynjs/runtime/Compiler.java
+++ b/src/main/java/org/dynjs/runtime/Compiler.java
@@ -59,7 +59,7 @@ public Compiler withSource(SourceProvider source) {
         return this;
     }
 
-    public Compiler withSource(File source) throws FileNotFoundException {
+    public Compiler withSource(File source) throws IOException {
         this.sourceProvider = new FileSourceProvider(source);
         this.fileName = source.getName();
         return this;
diff --git a/src/main/java/org/dynjs/runtime/DynJS.java b/src/main/java/org/dynjs/runtime/DynJS.java
index 610280692..ac3d6ce6f 100644
--- a/src/main/java/org/dynjs/runtime/DynJS.java
+++ b/src/main/java/org/dynjs/runtime/DynJS.java
@@ -45,15 +45,19 @@ public DynJS(Config config, JSObject globalObject) {
     private void loadKernel() {
         // FIXME only works for non-IR atm
         if (!Config.CompileMode.IR.equals(this.config.getCompileMode())) {
-            switch (this.config.getKernelMode()) {
-                case INTERNAL:
-                    // Load pure-JS kernel
-                    //this.evaluate(getClass().getResourceAsStream("/dynjs/kernel.js"));
-                    this.evaluate(new ClassLoaderSourceProvider(getClass().getClassLoader(), "dynjs/kernel.js"));
-                    break;
-                case EXTERNAL:
-                    this.evaluate(new FileSourceProvider(new File("src/main/resources/dynjs/kernel.js")));
-                    break;
+            try {
+                switch (this.config.getKernelMode()) {
+                    case INTERNAL:
+                        // Load pure-JS kernel
+                        //this.evaluate(getClass().getResourceAsStream("/dynjs/kernel.js"));
+                        this.evaluate(new ClassLoaderSourceProvider(getClass().getClassLoader(), "dynjs/kernel.js"));
+                        break;
+                    case EXTERNAL:
+                        this.evaluate(new FileSourceProvider(new File("src/main/resources/dynjs/kernel.js")));
+                        break;
+                }
+            } catch (IOException e) {
+                e.printStackTrace();
             }
         }
     }
diff --git a/src/main/java/org/dynjs/runtime/Runner.java b/src/main/java/org/dynjs/runtime/Runner.java
index 4c898f0c3..78fc81be7 100644
--- a/src/main/java/org/dynjs/runtime/Runner.java
+++ b/src/main/java/org/dynjs/runtime/Runner.java
@@ -83,7 +83,7 @@ public Runner withSource(SourceProvider source) {
         return this;
     }
 
-    public Runner withSource(File source) throws FileNotFoundException {
+    public Runner withSource(File source) throws IOException {
         this.compiler.withSource(source);
         return this;
     }
diff --git a/src/main/java/org/dynjs/runtime/SourceProvider.java b/src/main/java/org/dynjs/runtime/SourceProvider.java
index 2a85c7c88..cc54cc860 100644
--- a/src/main/java/org/dynjs/runtime/SourceProvider.java
+++ b/src/main/java/org/dynjs/runtime/SourceProvider.java
@@ -10,5 +10,13 @@ public interface SourceProvider {
 
     String getName();
 
+    long getSourceLength();
+
+    long getLineCount();
+
+    int getId();
+
     Reader openReader() throws IOException;
+
+    String getSource() throws IOException;
 }
diff --git a/src/main/java/org/dynjs/runtime/source/ClassLoaderSourceProvider.java b/src/main/java/org/dynjs/runtime/source/ClassLoaderSourceProvider.java
index 41e37ca4c..c2147c0bf 100644
--- a/src/main/java/org/dynjs/runtime/source/ClassLoaderSourceProvider.java
+++ b/src/main/java/org/dynjs/runtime/source/ClassLoaderSourceProvider.java
@@ -1,33 +1,13 @@
 package org.dynjs.runtime.source;
 
-import org.dynjs.runtime.SourceProvider;
-
-import java.io.*;
+import java.io.IOException;
 
 /**
  * @author Bob McWhirter
  */
-public class ClassLoaderSourceProvider implements SourceProvider {
-
-    private final ClassLoader classLoader;
-    private final String path;
-
-    public ClassLoaderSourceProvider(ClassLoader classLoader, String path) {
-        this.classLoader = classLoader;
-        this.path = path;
-    }
-
-    @Override
-    public String getName() {
-        return this.path;
-    }
-
-    public Reader openReader() throws IOException {
-        InputStream in = this.classLoader.getResourceAsStream(this.path);
-        if ( in == null ) {
-            throw new FileNotFoundException( this.path );
-        }
+public class ClassLoaderSourceProvider extends InputStreamSourceProvider {
 
-        return new InputStreamReader( in );
+    public ClassLoaderSourceProvider(ClassLoader classLoader, String path) throws IOException {
+        super(classLoader.getResourceAsStream(path), path);
     }
 }
diff --git a/src/main/java/org/dynjs/runtime/source/FileSourceProvider.java b/src/main/java/org/dynjs/runtime/source/FileSourceProvider.java
index 82c739b0f..d6d850ab3 100644
--- a/src/main/java/org/dynjs/runtime/source/FileSourceProvider.java
+++ b/src/main/java/org/dynjs/runtime/source/FileSourceProvider.java
@@ -7,19 +7,10 @@
 /**
  * @author Bob McWhirter
  */
-public class FileSourceProvider implements SourceProvider {
+public class FileSourceProvider extends InputStreamSourceProvider {
 
-    private final File file;
-
-    public FileSourceProvider(File file) {
-        this.file = file;
-    }
-
-    public String getName() {
-        return file.getAbsolutePath();
+    public FileSourceProvider(File file) throws IOException {
+        super( new FileInputStream( file ), file.getAbsolutePath() );
     }
 
-    public Reader openReader() throws IOException {
-        return new FileReader( this.file );
-    }
 }
diff --git a/src/main/java/org/dynjs/runtime/source/StringSourceProvider.java b/src/main/java/org/dynjs/runtime/source/StringSourceProvider.java
index f210ebeb7..2edac30fd 100644
--- a/src/main/java/org/dynjs/runtime/source/StringSourceProvider.java
+++ b/src/main/java/org/dynjs/runtime/source/StringSourceProvider.java
@@ -9,8 +9,11 @@
  */
 public class StringSourceProvider implements SourceProvider {
 
+    private static int COUNTER = 0;
+
     private final String source;
     private final String name;
+    private final int id;
 
     public StringSourceProvider(String source) {
         this( source, "<script>" );
@@ -19,6 +22,7 @@ public StringSourceProvider(String source) {
     public StringSourceProvider(String source, String name) {
         this.source = source;
         this.name = name;
+        this.id = ++COUNTER;
     }
 
     @Override
@@ -26,6 +30,24 @@ public String getName() {
         return this.name;
     }
 
+    @Override
+    public int getId() {
+        return this.id;
+    }
+
+    @Override
+    public String getSource() {
+        return this.source;
+    }
+
+    public long getLineCount() {
+        return 99;
+    }
+
+    public long getSourceLength() {
+        return 99;
+    }
+
     public Reader openReader() throws IOException {
         return new StringReader( this.source );
     }