diff --git a/pom.xml b/pom.xml
index 6158b58b7..edf8f411e 100644
--- a/pom.xml
+++ b/pom.xml
@@ -84,7 +84,21 @@
 	</configuration>
       </plugin>
       <plugin>
-	<groupId>org.codehaus.mojo</groupId>
+    <groupId>org.apache.maven.plugins</groupId>
+    <artifactId>maven-source-plugin</artifactId>
+    <version>2.4</version>
+    <executions>
+      <execution>
+        <id>attach-sources</id>
+        <goals>
+          <goal>jar</goal>
+          <goal>test-jar</goal>
+        </goals>
+      </execution>
+    </executions>
+      </plugin>
+      <plugin>
+    <groupId>org.codehaus.mojo</groupId>
 	<artifactId>build-helper-maven-plugin</artifactId>
 	<version>1.9.1</version>
 	<executions>
diff --git a/src/main/java/com/impossibl/postgres/system/procs/BinaryDecoder.java b/src/main/java/com/impossibl/postgres/system/procs/BinaryDecoder.java
index 5ff8dfa55..c18491a52 100644
--- a/src/main/java/com/impossibl/postgres/system/procs/BinaryDecoder.java
+++ b/src/main/java/com/impossibl/postgres/system/procs/BinaryDecoder.java
@@ -37,7 +37,7 @@
 
 public abstract class BinaryDecoder implements Type.Codec.Decoder {
 
-  abstract Object decode(Type type, Short typeLength, Integer typeModifier, ByteBuf buffer, Context context) throws IOException;
+  protected abstract Object decode(Type type, Short typeLength, Integer typeModifier, ByteBuf buffer, Context context) throws IOException;
 
   @Override
   public Object decode(Type type, Short typeLength, Integer typeModifier, Object buffer, Context context) throws IOException {
diff --git a/src/main/java/com/impossibl/postgres/system/procs/BinaryEncoder.java b/src/main/java/com/impossibl/postgres/system/procs/BinaryEncoder.java
index ef9e977a7..ce7d6996a 100644
--- a/src/main/java/com/impossibl/postgres/system/procs/BinaryEncoder.java
+++ b/src/main/java/com/impossibl/postgres/system/procs/BinaryEncoder.java
@@ -38,7 +38,7 @@
 
 public abstract class BinaryEncoder implements Type.Codec.Encoder {
 
-  abstract void encode(Type type, ByteBuf buffer, Object val, Context context) throws IOException;
+  protected abstract void encode(Type type, ByteBuf buffer, Object val, Context context) throws IOException;
 
   @Override
   public void encode(Type type, Object buffer, Object value, Context context) throws IOException {
diff --git a/src/main/java/com/impossibl/postgres/system/procs/Dates.java b/src/main/java/com/impossibl/postgres/system/procs/Dates.java
index dc9a247a5..bc4b558d1 100644
--- a/src/main/java/com/impossibl/postgres/system/procs/Dates.java
+++ b/src/main/java/com/impossibl/postgres/system/procs/Dates.java
@@ -204,7 +204,7 @@ public Class<?> getOutputType() {
     }
 
     @Override
-    Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
+    protected Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
 
       Map<String, Object> pieces = new HashMap<>();
 
@@ -228,7 +228,7 @@ public Class<?> getInputType() {
     }
 
     @Override
-    void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
+    protected void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
 
       String strVal = context.getDateFormatter().getPrinter().format((Instant) val);
 
diff --git a/src/main/java/com/impossibl/postgres/system/procs/TextDecoder.java b/src/main/java/com/impossibl/postgres/system/procs/TextDecoder.java
index add01a693..0ddc481fd 100644
--- a/src/main/java/com/impossibl/postgres/system/procs/TextDecoder.java
+++ b/src/main/java/com/impossibl/postgres/system/procs/TextDecoder.java
@@ -37,7 +37,7 @@
 
 public abstract class TextDecoder implements Type.Codec.Decoder {
 
-  abstract Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException;
+  protected abstract Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException;
 
   @Override
   public Object decode(Type type, Short typeLength, Integer typeModifier, Object buffer, Context context) throws IOException {
diff --git a/src/main/java/com/impossibl/postgres/system/procs/TextEncoder.java b/src/main/java/com/impossibl/postgres/system/procs/TextEncoder.java
index e9d98cd69..d5fabc7f3 100644
--- a/src/main/java/com/impossibl/postgres/system/procs/TextEncoder.java
+++ b/src/main/java/com/impossibl/postgres/system/procs/TextEncoder.java
@@ -37,7 +37,7 @@
 
 public abstract class TextEncoder implements Type.Codec.Encoder {
 
-  abstract void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException;
+  protected abstract void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException;
 
   @Override
   public void encode(Type type, Object buffer, Object value, Context context) throws IOException {
diff --git a/src/main/java/com/impossibl/postgres/system/procs/Tids.java b/src/main/java/com/impossibl/postgres/system/procs/Tids.java
index e8ac69934..dfc13a835 100644
--- a/src/main/java/com/impossibl/postgres/system/procs/Tids.java
+++ b/src/main/java/com/impossibl/postgres/system/procs/Tids.java
@@ -58,7 +58,7 @@ public Class<?> getOutputType() {
     }
 
     @Override
-    Object decode(Type type, Short typeLength, Integer typeModifier, ByteBuf buffer, Context context) throws IOException {
+    protected Object decode(Type type, Short typeLength, Integer typeModifier, ByteBuf buffer, Context context) throws IOException {
 
       int length = buffer.readInt();
       if (length == -1) {
@@ -89,7 +89,7 @@ public Class<?> getInputType() {
     }
 
     @Override
-    void encode(Type type, ByteBuf buffer, Object val, Context context) throws IOException {
+    protected void encode(Type type, ByteBuf buffer, Object val, Context context) throws IOException {
 
       if (val == null) {
 
@@ -126,7 +126,7 @@ public Class<?> getOutputType() {
     }
 
     @Override
-    Tid decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
+    protected Tid decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
 
       String[] items = buffer.subSequence(1, buffer.length() - 1).toString().split(",");
 
@@ -151,7 +151,7 @@ public Class<?> getInputType() {
     }
 
     @Override
-    void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
+    protected void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
 
       Tid tid = (Tid) val;
 
diff --git a/src/main/java/com/impossibl/postgres/system/procs/TimesWithTZ.java b/src/main/java/com/impossibl/postgres/system/procs/TimesWithTZ.java
index 08b966d12..d620c6cc8 100644
--- a/src/main/java/com/impossibl/postgres/system/procs/TimesWithTZ.java
+++ b/src/main/java/com/impossibl/postgres/system/procs/TimesWithTZ.java
@@ -145,7 +145,7 @@ public Class<?> getOutputType() {
     }
 
     @Override
-    Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
+    protected Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
 
       Map<String, Object> pieces = new HashMap<>();
 
@@ -169,7 +169,7 @@ public Class<?> getInputType() {
     }
 
     @Override
-    void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
+    protected void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
 
       String strVal = context.getTimeFormatter().getPrinter().format((Instant) val);
 
diff --git a/src/main/java/com/impossibl/postgres/system/procs/TimesWithoutTZ.java b/src/main/java/com/impossibl/postgres/system/procs/TimesWithoutTZ.java
index f11b567db..ef2ee2563 100644
--- a/src/main/java/com/impossibl/postgres/system/procs/TimesWithoutTZ.java
+++ b/src/main/java/com/impossibl/postgres/system/procs/TimesWithoutTZ.java
@@ -135,7 +135,7 @@ public Class<?> getOutputType() {
     }
 
     @Override
-    Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
+    protected Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
 
       Map<String, Object> pieces = new HashMap<>();
 
@@ -159,7 +159,7 @@ public Class<?> getInputType() {
     }
 
     @Override
-    void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
+    protected void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
 
       String strVal = context.getTimeFormatter().getPrinter().format((Instant) val);
 
diff --git a/src/main/java/com/impossibl/postgres/system/procs/Timestamps.java b/src/main/java/com/impossibl/postgres/system/procs/Timestamps.java
index 7d458d049..90971d3ff 100644
--- a/src/main/java/com/impossibl/postgres/system/procs/Timestamps.java
+++ b/src/main/java/com/impossibl/postgres/system/procs/Timestamps.java
@@ -190,7 +190,7 @@ public Class<?> getOutputType() {
     }
 
     @Override
-    Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
+    protected Object decode(Type type, Short typeLength, Integer typeModifier, CharSequence buffer, Context context) throws IOException {
 
       Map<String, Object> pieces = new HashMap<>();
 
@@ -220,7 +220,7 @@ public Class<?> getInputType() {
     }
 
     @Override
-    void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
+    protected void encode(Type type, StringBuilder buffer, Object val, Context context) throws IOException {
 
       String strVal = context.getTimestampFormatter().getPrinter().format((Instant) val);
 
diff --git a/src/test/java/com/impossibl/postgres/jdbc/CodecTest.java b/src/test/java/com/impossibl/postgres/jdbc/CodecTest.java
index 0d2bd0c06..485cb7efc 100644
--- a/src/test/java/com/impossibl/postgres/jdbc/CodecTest.java
+++ b/src/test/java/com/impossibl/postgres/jdbc/CodecTest.java
@@ -85,9 +85,9 @@
 @RunWith(Parameterized.class)
 public class CodecTest {
 
-  PGConnectionImpl conn;
-  String typeName;
-  Object value;
+  protected PGConnectionImpl conn;
+  protected String typeName;
+  protected Object value;
 
   public CodecTest(String typeName, Object value) {
     this.typeName = typeName;
@@ -340,7 +340,7 @@ private void assertStreamEquals(InputStream expected, InputStream actual) throws
     assertArrayEquals(ByteStreams.toByteArray(expected), ByteStreams.toByteArray(actual));
   }
 
-  interface Maker {
+  public interface Maker {
     Object make(PGConnectionImpl conn) throws SQLException;
   }
 
@@ -447,6 +447,10 @@ public Object make(PGConnectionImpl conn) throws SQLException {
       {"tid", new PGRowId(new Tid(0, (short) 1))},
     };
 
+    return expandDataTypesToStructsAndArrays(scalarTypesData);
+  }
+
+  public static Collection<Object[]> expandDataTypesToStructsAndArrays(Object[][] scalarTypesData) {
     List<Object[]> data = new ArrayList<>();
 
     //Combine entries with generated ones for array and composite testing
@@ -514,7 +518,7 @@ public Object make(PGConnectionImpl conn) throws SQLException {
     return data;
   }
 
-  static Map<String, String> typeCasts;
+  protected static Map<String, String> typeCasts;
   static {
     typeCasts = new HashMap<>();
     typeCasts.put("bit", "bit(7)");