diff --git a/README.md b/README.md
index f1a5897..2ada957 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,9 @@ Limitations
 * `MPFloat` uses the data type you're using to decide on precision (float 32 or 64) - not the actual value. E.g. 0.5
   could be saved perfectly as a float 42, but if you provide a double value, it will be stored as float 64, wasting
   4 bytes.
+* If you want to use the 'ext format family', you'll need to implement and register your own `MPType` and
+  `MPType.Unpacker`. Be aware that they take precedence over the default unpackers, meaning if you accidentally define
+  your unpacker to handle strings, for example, you won't be able to unpack any regular strings anymore.
 
 Setup
 -----
diff --git a/src/main/java/ch/dissem/msgpack/Reader.java b/src/main/java/ch/dissem/msgpack/Reader.java
index 9b4e5ee..e24ebf8 100644
--- a/src/main/java/ch/dissem/msgpack/Reader.java
+++ b/src/main/java/ch/dissem/msgpack/Reader.java
@@ -27,7 +27,7 @@ import java.util.List;
  * Reads MPType object from an {@link InputStream}.
  */
 public class Reader {
-    private List<MPType.Unpacker<?>> unpackers = new LinkedList<>();
+    private LinkedList<MPType.Unpacker<?>> unpackers = new LinkedList<>();
 
     private static final Reader instance = new Reader();
 
@@ -50,7 +50,7 @@ public class Reader {
      * Register your own extensions
      */
     public void register(MPType.Unpacker<?> unpacker) {
-        unpackers.add(unpacker);
+        unpackers.addFirst(unpacker);
     }
 
     public MPType read(InputStream in) throws IOException {