diff --git a/btree.h b/btree.h
index 206410e..2164e3e 100644
--- a/btree.h
+++ b/btree.h
@@ -5,10 +5,33 @@
 
 enum treeTypes { BT_CUSTOM, BT_PCHAR, BT_STRING, BT_SINGLE, BT_DOUBLE, BT_INT32, BT_INT64 };
 
-struct TBlockRun {
+typedef struct blockRun_t {
   int32  AG;
   uInt16 start;
   uInt16 len;
-};
+} __attribute__((__packed__));
+
+typedef blockRun_t inodeAddr;
+
+typedef union {
+  int32     i;
+  uInt32    u;
+  float     f;
+  double    d;
+  void *    p;
+  inodeAddr iAddr;
+  int64     offset;
+} uPtr;  
+
+typedef struct bNodeData_t {
+  uPtr      link;
+  union {
+    char    str[1];
+    float   f;
+    double  d;
+    int32   i;
+    int64   x;
+  } key;
+} __attribute__((__packed__));
 
 #endif