diff --git a/lib/inst.c b/lib/inst.c
index 3c1eb4a..6198387 100644
--- a/lib/inst.c
+++ b/lib/inst.c
@@ -382,7 +382,7 @@ int inst_read_bytecode(inst_t *ptr, byte_t *bytes, size_t size_bytes)
   static_assert(NUMBER_OF_OPCODES == 99, "inst_read_bytecode: Out of date");
 
   opcode_t opcode = *(bytes++);
-  if (opcode > OP_HALT || opcode < OP_NOOP)
+  if (opcode >= NUMBER_OF_OPCODES || opcode < OP_NOOP)
     return READ_ERR_INVALID_OPCODE;
 
   inst_t inst = {opcode, {0}};
diff --git a/lib/inst.h b/lib/inst.h
index 6f14830..6b7cbfe 100644
--- a/lib/inst.h
+++ b/lib/inst.h
@@ -28,6 +28,7 @@
 typedef enum
 {
   OP_NOOP = 0,
+  OP_HALT,
 
   // Dealing with data and registers
   OP_PUSH_BYTE,
@@ -161,7 +162,6 @@ typedef enum
   OP_CALL_STACK,
   OP_RET,
 
-  OP_HALT,
   // Should not be an opcode
   NUMBER_OF_OPCODES,
 } opcode_t;